Re: [sage-devel] Re: About Graph.to_partition and Poset.to_graph
Helloo everybody ! This discussion seemed to have stopped, so I create ticket #17449. >From the discussions it appeared that some persons cared about the feature of to_partition, and so the ticket creates a new function connected_components_sizes() which returns the (sorted) list of connected components sizes. The Poset.to_graph function, on the other hand, is deprecated with a message explaining how to obtain the same result by other means. Please bring your remarks to the ticket is you believe that it is wrong, and tell us why ! Nathann http://trac.sagemath.org/ticket/17449 -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Re: Maple versus Mathematica
Thanks for passing Greg's evaluation of this on - that sounds about right. (sage-edu, see https://groups.google.com/d/msg/sage-devel/x3h4m3LjWkI/gKfpnAijS5UJ ) I do think that more books is a real "selling" point. Remember how you were contacted about the Use-Sage series... I will again be road-testing my number theory text (nearly orthogonal to yours, William) this spring, for what it's worth, but I think if we can come up with creative (possibly non-monetary, or not primarily that) incentives to have people write more Sage-enabled texts, it will be key. Even better would be to find people to write lab manuals for texts that already have significant portions in other languages but that are essentially language-agnostic. I can think of several I have *used* off the top of my head. Getting Sage as a 'normal' solution to go along with such texts will be very useful. (But who will do this? It will require work that will likely be unrewarded by both tenure committees and publishers.) -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Running Sage.app installed by another user
On Dec 5, 2014, at 9:07 AM, Jérôme Tremblay wrote: > Under OSX Yosemite, I try to install Sage 6.4.1 app in the system > applications. > > When I run sage as admin, everything works fine. However, when my users try > to run Sage, they get a warning that they are trying to execute Sage from a > read-only filesystem. > > My question is : > > It it safe to execute Sage.app if it's installed by the admin? If so, how do > I suppress the warning? If not, what can I do? I can't really start > installing a the whole Sage in each of my users personal space…. As a very cheap suppression of the warning, you could chmod go+w /path/to/Sage.app/Contents/Resources/sage/sage -Ivan -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Fwd: [sage-devel] Re: Maple versus Mathematica
Hi, Gregory Bard sent me a very nice email comparing his book to the "Calcul avec Sage" and explaining how the audience for the two books are related. William -- Forwarded message -- From: Gregory Bard Date: Fri, Dec 5, 2014 at 3:22 PM Subject: Re: [sage-devel] Re: Maple versus Mathematica To: William Stein Hi there. I very much apologize for the late reply. This is the busiest time of the year for me. "Calcul avec Sage" is an amazing work. Being for an audience in France, it is going after the French curriculum. It assumes a level of sophistication that is equivalent to a certain point in an American math major's or physics's majors education. Some of the material would be suitable for Calculus III, Differential Equations, or Discrete Math, which are very common 200-level courses. The remainder, probably the majority, is more at the 400-level in our system. "Sage for Undergraduates" is aiming only a single level lower, at the Calculus II / Calculus III level. However, the issue is that I was hoping to meet the needs of students in engineering, finance, chemistry, and maybe the most mathematical of economics PhD students. By having a broader audience, that means my book is a full two levels lower. In other words, a sophomore mathematics major should find my book "a breeze" but "useful and informative." Perhaps someone from the nearby disciplines would find my book "challenging but useful." I think "Calcul avec Sage" would, after translation, be challenging for an American sophomore math major, suitable for a junior math major, and extremely handy for a senior math major. Physics majors would rate the book similarly, perhaps with a slight offset. Engineering majors would experience some substantial challenges, and for chemistry and finance, I would upgrade this to "rather challenging." An economics major would probably be demolished by "Calcul avec Sage." Also, my tone is very casual and informal, whereas Calcul is scholarly, but still very readable. I found the French used in "Calcul avec Sage" to be very readable and crisp, without the excessive use of minor subjunctive tenses found in some other French academic writing. I enjoyed working with that book when writing mine. An important variable would be the work of Joyner on differential equations (which is in print, coauthored with Marshall Hampton), and "Differential Calculus and Sage" (coauthored with William Granville). Those are books for DiffEq and Calc I, as course textbooks, but using Sage. That avenue to me seems to be most fruitful. After all, we've seen the success of Beezer's book on Linear Algebra. Of course, all this is my opinion. I think I'd like to add another 12 projects to "Sage for Undergraduates" for the second edition, but I ran out of time---and honestly I kind of ran low on creativity. I think that the existing projects are high quality, but too few---being 6 or 7 depending on how you count. By the way, thanks for all your support during the "Sage for Undergraduates" process. The book would not exist at all without you and your introducing me to Ina Mette. I am very grateful for your support. If I can clarify with more details, please email me!! ---Greg p.s. Again, apologies for the late reply. On Mon, Dec 1, 2014 at 8:54 AM, William Stein wrote: > Greg, > > Might you have any comments on the relationship in terms of scope of > your book to Zimmerman et al's "Calcul mathématique avec Sage"? This > came up in a discussion on sage-devel about translation. > > > -- Forwarded message -- > From: Bruno Grenet > Date: Mon, Dec 1, 2014 at 6:09 AM > Subject: Re: [sage-devel] Re: Maple versus Mathematica > To: sage-devel@googlegroups.com > > > > Le 01/12/2014 08:53, Nathann Cohen a écrit : >> >> Kanappan wanted to work on an english translation at some point, but there >> was no news since and he work in Canada nowadays. Not sure that he has a lot >> of time for that. >>> >>> I guess the number of available books on Maple and >>> Mathematica is a reason for some teachers to choose these languages. To my >>> mind, it would be much more efficient (though maybe more work too) than a >>> marketing document! >> >> The good thing is that we do not even have to chose between the two. > > > Of course! As a first step for a translation, we should maybe > investigate to find an appropriate free software to support > collaborative translation. I guess it is a huge work to do it alone, > it is maybe more feasible if we are a group of people working on this. > > Yet I now remember the existence Gregory Bard's "Sage for > Undergraduates" that has a similar goal, making a translation of > "Calcul mathématique avec Sage" less needed. > > Bruno > > -- > You received this message because you are subscribed to the Google > Groups "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send > an email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send
Re: [sage-devel] Bug in abs(I*x).diff(x)
On Fri, Dec 5, 2014 at 1:20 PM, Ondřej Čertík wrote: > Hi Bill, > > I thought about this a lot (essentially I studied complex analysis > from several books as well as consulted with many colleagues) and I > figured out some answers to my questions. > > In the approach (A), you have: > > log(a*b) = log(a) + log(b) > > What that means is that log() is multivalued, so you can add 2*pi*i*n > for all "n". The way to do arithmetic and compare multivalued > functions is simply to make sure that the infinite (sometimes it could > be finite) set of values on the left is equivalent to the infinite set > of values on the right. In other words, if you pick a value on the > left, for the sake of an argument let's say a=b=-1 and we pick n = 5, > so we get log(a*b) = log(1) = 0 + 2*pi*i*5 = 10*pi*i, then if you can > find combinations of values on the right hand side to make the result > equal to 10*pi*i, and you can do this for all integer "n", and if you > can do the opposite, i.e. that you pick any combination of values on > the right hand side and are able to find a value on the left hand side > that is equal to it, then you prove the equality. I.e. you prove that > the infinite set of multivalues on the left hand side and right hand > side are equal. > > Once we have an understanding how log(z) works, we simply can derive > all kinds of formulas in the approach (A). The way it works is that > you put in the 2*pi*n factors, i.e. you explicitly enumerate all > possibilities, then you derive some formulas, and at the end you > absorb the 2*pi*n factors into the multivalued functions, i.e. you can > always absorb 2*pi*i*n into log(). But sometimes it might not be > possible to completely absorb all these factors. > > Now let's apply this to the problems below: > > On Wed, Nov 26, 2014 at 10:27 PM, Bill Page > wrote: >> On 26 November 2014 at 12:58, Ondřej Čertík wrote: >>> On Wed, Nov 26, 2014 at 10:17 AM, Bill Page >>> wrote: Does it help if a say the operations are defined "symbolically"? >>> >>> All I want is if you can give me an algorithm of your approach >>> in sufficient detail, so that it can be implemented by me on a >>> computer. And by "your approach", I mean an approach, where >>> conjugate(log(x)) = log(conjugate(x)) for all x. >>> >> >> I am sorry, we seem to be having some trouble communicating. Is that >> something infecting this email list? :) >> >> Making "conjugate(log(x)) = log(conjugate(x)) for all x" is trivial >> so long as it is treated symbolically: the 'conjugate' operation is >> just defined to rewrite itself (auto-simplify) when applied to any >> operand of the form log(_), so 'conjugate(log(_))' is evaluated as >> 'log(conjugate(_))', where _ stands for any element of the domain >> Expression. This is what I meant when I said it was considered true >> by definition, i.e. by definition of the symbolic 'conjugate' >> operation. Exactly the same sort of thing happens when the >> 'conjugate' operation acts on 'conjugate' so that >> 'conjugate(conjugate(x))' is simply rewritten as 'x'. > > Sure, on this level you can implement it. I was thinking on a deeper > level, i.e. imagining putting a number x=-1 in and see how could this be true: > > conjugate(log(-1)) = log(conjugate(-1)) > > The answer that I was looking for is this: > > LHS: conjugate(log(-1)) = conjugate(i*pi + 2*pi*i*n) = -i*pi-2*pi*i*n > RHS: log(conjugate(-1)) = log(-1) = i*pi + 2*pi*i*m > > If we pick n=-m-1, we always get LHS=RHS, so the two infinite set of > multivalues are equivalent, and the relation conjugate(log(-1)) = > log(conjugate(-1)) holds. > When you evaluate log(-1), you cannot just give i*pi, you need to give > all the multivalues. But otherwise it works. > >> >>> I have provided all the details of the algorithm (B). In approach (B), >>> it is not true that >>> conjugate(log(x)) = log(conjugate(x)) for all x. >>> >>> This equation (when conjugate(log(x)) = log(conjugate(x)) holds) >>> started this whole discussion. >> >> That >> >> log(a*b) = log(a) + log(b) >> >> is considerably less trivial that the case of 'conjugate'. From my >> point of view that is what actually started this branch of the >> "fabric" of this discussion. That is where 'normalize' comes in. > > I think the above answers both, it all works and is consistent in the > approach (A). You just need to remember that if a function is > multivalued, e.g. log(z), then you always need to enumerate all the > values and prove that the LHS is equivalent to RHS. > > There is a theorem, that says that actually, if you give me a complex > function values on just one branch, I can reconstruct the function in > all branches. So it is probably the case that you only need to find > one set of "n", "m" and "k" to satisfy the equation and it will then > hold for the other values as well. But for clarity, I always prove it > for all values. > >> >>> So I was trying to understand your approach how to make this hold >>> for all "x", and I suggeste
Re: [sage-devel] Re: What are we unable to do right now ?
On Fri, Dec 5, 2014 at 12:45 PM, maldun wrote: > I agree with you that it is not that important as it was some years ago. > Nevertheless be aware that many professional users in engineering > and research can't go online that simply, because of security reasons, and > company policies (I know that from first hand), > and they are a big market which we should not underestimate. You are of course 100% right, and adding the above about for what group of users windows support is important just helps make this item on the list "What are we unable to do right now?" clearer. -- William > > On Friday, December 5, 2014 9:39:55 PM UTC+1, William wrote: >> >> On Fri, Dec 5, 2014 at 12:19 PM, maldun wrote: >> > What we still don't have is a working windows version. This is still a >> > big >> > blocker for being succesfull. >> >> I don't want to in any way discourage anybody from working hard on >> Windows support for Sage. However, it's getting more difficult to >> argue that Windows support is a blocker to our mission statement. >> >> As I've explained elsewhere, I started SageMathCloud because of >> exactly this problem, and also that I'm thinking about where >> technology is going to be in a few years rather than where it was. >> I'm not arguing the SMC is *the* solution, just that web-based >> approaches are, including Sage cell server, Wakari, etc. >> >> There's no question that in say 200?, Microsoft Windows support was >> absolutely critical for widespread adoption of a piece of software in >> a given market. Today, and certainly going into the future, this is >> not so clear.The single most popular applications in the world >> today are Google.com and Facebook.com [1], which have well over a >> *billion* active users [2], and neither has a "working windows >> version".And it appears based on [3] and blogs that much of the >> math software development work by Wolfram Inc is about making >> Mathematica available online. >> >> Online is where the puck is going. Actually, it is arguably where the >> puck already is. (For huge applications, mobile is just a different >> interface to online.) >> >> -- William >> >> [1] http://www.alexa.com/topsites >> [2] http://newsroom.fb.com/company-info/ >> [3] https://www.wolframcloud.com/ >> >> > >> > On Friday, December 5, 2014 8:17:44 AM UTC+1, Nathann Cohen wrote: >> >> >> >> Helloo everybody ! >> >> >> >> I am preparing some Sage talk, and I wanted to say at some point: >> >> "Honestly we are not that good. We have strong points but we miss many >> >> things too. It all depends on what the developpers are interested in: >> >> we are >> >> great on some research areas, and under water level on others" >> >> >> >> Somehow this question is also related to William's "Sage has failed", >> >> as >> >> we cannot be a replacement for Mathematica/Maple/ unless we cover >> >> all >> >> kinds of mathematics. >> >> >> >> In your past experiences (possibly when using Sage to teach in a >> >> classroom), in which areas do you think we are behind users' >> >> expectations ? >> >> >> >> If we had such a list, we could even start asking people around "Do you >> >> work on X ? Cool, we need your help for something big". We could also >> >> have a >> >> list of such domains on our website, and do some (cheap) propaganda >> >> like: >> >> >> >> "Sage as in 'Free Beer': if you can help us develop Sage's features in >> >> the >> >> areas above, we owe you one. Actually we owe you many. Become a >> >> contributor >> >> and be rewarded with a free beer from every Sage developper you will >> >> meet >> >> around the world" >> >> >> >> We have to know what we cannot do. So let's make a list. >> >> >> >> Nathann >> > >> > -- >> > You received this message because you are subscribed to the Google >> > Groups >> > "sage-devel" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> > an >> > email to sage-devel+...@googlegroups.com. >> > To post to this group, send email to sage-...@googlegroups.com. >> > Visit this group at http://groups.google.com/group/sage-devel. >> > For more options, visit https://groups.google.com/d/optout. >> >> >> >> -- >> William Stein >> Professor of Mathematics >> University of Washington >> http://wstein.org > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. -- William Stein Professor of Mathematics University of Washington http://wstein.org -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubs
Re: [sage-devel] Re: What are we unable to do right now ?
I agree with you that it is not that important as it was some years ago. Nevertheless be aware that many professional users in engineering and research can't go online that simply, because of security reasons, and company policies (I know that from first hand), and they are a big market which we should not underestimate. On Friday, December 5, 2014 9:39:55 PM UTC+1, William wrote: > > On Fri, Dec 5, 2014 at 12:19 PM, maldun > > wrote: > > What we still don't have is a working windows version. This is still a > big > > blocker for being succesfull. > > I don't want to in any way discourage anybody from working hard on > Windows support for Sage. However, it's getting more difficult to > argue that Windows support is a blocker to our mission statement. > > As I've explained elsewhere, I started SageMathCloud because of > exactly this problem, and also that I'm thinking about where > technology is going to be in a few years rather than where it was. > I'm not arguing the SMC is *the* solution, just that web-based > approaches are, including Sage cell server, Wakari, etc. > > There's no question that in say 200?, Microsoft Windows support was > absolutely critical for widespread adoption of a piece of software in > a given market. Today, and certainly going into the future, this is > not so clear.The single most popular applications in the world > today are Google.com and Facebook.com [1], which have well over a > *billion* active users [2], and neither has a "working windows > version".And it appears based on [3] and blogs that much of the > math software development work by Wolfram Inc is about making > Mathematica available online. > > Online is where the puck is going. Actually, it is arguably where the > puck already is. (For huge applications, mobile is just a different > interface to online.) > > -- William > > [1] http://www.alexa.com/topsites > [2] http://newsroom.fb.com/company-info/ > [3] https://www.wolframcloud.com/ > > > > > On Friday, December 5, 2014 8:17:44 AM UTC+1, Nathann Cohen wrote: > >> > >> Helloo everybody ! > >> > >> I am preparing some Sage talk, and I wanted to say at some point: > >> "Honestly we are not that good. We have strong points but we miss many > >> things too. It all depends on what the developpers are interested in: > we are > >> great on some research areas, and under water level on others" > >> > >> Somehow this question is also related to William's "Sage has failed", > as > >> we cannot be a replacement for Mathematica/Maple/ unless we cover > all > >> kinds of mathematics. > >> > >> In your past experiences (possibly when using Sage to teach in a > >> classroom), in which areas do you think we are behind users' > expectations ? > >> > >> If we had such a list, we could even start asking people around "Do you > >> work on X ? Cool, we need your help for something big". We could also > have a > >> list of such domains on our website, and do some (cheap) propaganda > like: > >> > >> "Sage as in 'Free Beer': if you can help us develop Sage's features in > the > >> areas above, we owe you one. Actually we owe you many. Become a > contributor > >> and be rewarded with a free beer from every Sage developper you will > meet > >> around the world" > >> > >> We have to know what we cannot do. So let's make a list. > >> > >> Nathann > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "sage-devel" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to sage-devel+...@googlegroups.com . > > To post to this group, send email to sage-...@googlegroups.com > . > > Visit this group at http://groups.google.com/group/sage-devel. > > For more options, visit https://groups.google.com/d/optout. > > > > -- > William Stein > Professor of Mathematics > University of Washington > http://wstein.org > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Re: What are we unable to do right now ?
On Fri, Dec 5, 2014 at 12:19 PM, maldun wrote: > What we still don't have is a working windows version. This is still a big > blocker for being succesfull. I don't want to in any way discourage anybody from working hard on Windows support for Sage. However, it's getting more difficult to argue that Windows support is a blocker to our mission statement. As I've explained elsewhere, I started SageMathCloud because of exactly this problem, and also that I'm thinking about where technology is going to be in a few years rather than where it was. I'm not arguing the SMC is *the* solution, just that web-based approaches are, including Sage cell server, Wakari, etc. There's no question that in say 200?, Microsoft Windows support was absolutely critical for widespread adoption of a piece of software in a given market. Today, and certainly going into the future, this is not so clear.The single most popular applications in the world today are Google.com and Facebook.com [1], which have well over a *billion* active users [2], and neither has a "working windows version".And it appears based on [3] and blogs that much of the math software development work by Wolfram Inc is about making Mathematica available online. Online is where the puck is going. Actually, it is arguably where the puck already is. (For huge applications, mobile is just a different interface to online.) -- William [1] http://www.alexa.com/topsites [2] http://newsroom.fb.com/company-info/ [3] https://www.wolframcloud.com/ > > On Friday, December 5, 2014 8:17:44 AM UTC+1, Nathann Cohen wrote: >> >> Helloo everybody ! >> >> I am preparing some Sage talk, and I wanted to say at some point: >> "Honestly we are not that good. We have strong points but we miss many >> things too. It all depends on what the developpers are interested in: we are >> great on some research areas, and under water level on others" >> >> Somehow this question is also related to William's "Sage has failed", as >> we cannot be a replacement for Mathematica/Maple/ unless we cover all >> kinds of mathematics. >> >> In your past experiences (possibly when using Sage to teach in a >> classroom), in which areas do you think we are behind users' expectations ? >> >> If we had such a list, we could even start asking people around "Do you >> work on X ? Cool, we need your help for something big". We could also have a >> list of such domains on our website, and do some (cheap) propaganda like: >> >> "Sage as in 'Free Beer': if you can help us develop Sage's features in the >> areas above, we owe you one. Actually we owe you many. Become a contributor >> and be rewarded with a free beer from every Sage developper you will meet >> around the world" >> >> We have to know what we cannot do. So let's make a list. >> >> Nathann > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. -- William Stein Professor of Mathematics University of Washington http://wstein.org -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Bug in abs(I*x).diff(x)
Hi Bill, I thought about this a lot (essentially I studied complex analysis from several books as well as consulted with many colleagues) and I figured out some answers to my questions. In the approach (A), you have: log(a*b) = log(a) + log(b) What that means is that log() is multivalued, so you can add 2*pi*i*n for all "n". The way to do arithmetic and compare multivalued functions is simply to make sure that the infinite (sometimes it could be finite) set of values on the left is equivalent to the infinite set of values on the right. In other words, if you pick a value on the left, for the sake of an argument let's say a=b=-1 and we pick n = 5, so we get log(a*b) = log(1) = 0 + 2*pi*i*5 = 10*pi*i, then if you can find combinations of values on the right hand side to make the result equal to 10*pi*i, and you can do this for all integer "n", and if you can do the opposite, i.e. that you pick any combination of values on the right hand side and are able to find a value on the left hand side that is equal to it, then you prove the equality. I.e. you prove that the infinite set of multivalues on the left hand side and right hand side are equal. Once we have an understanding how log(z) works, we simply can derive all kinds of formulas in the approach (A). The way it works is that you put in the 2*pi*n factors, i.e. you explicitly enumerate all possibilities, then you derive some formulas, and at the end you absorb the 2*pi*n factors into the multivalued functions, i.e. you can always absorb 2*pi*i*n into log(). But sometimes it might not be possible to completely absorb all these factors. Now let's apply this to the problems below: On Wed, Nov 26, 2014 at 10:27 PM, Bill Page wrote: > On 26 November 2014 at 12:58, Ondřej Čertík wrote: >> On Wed, Nov 26, 2014 at 10:17 AM, Bill Page >> wrote: >>> >>> Does it help if a say the operations are defined "symbolically"? >> >> All I want is if you can give me an algorithm of your approach >> in sufficient detail, so that it can be implemented by me on a >> computer. And by "your approach", I mean an approach, where >> conjugate(log(x)) = log(conjugate(x)) for all x. >> > > I am sorry, we seem to be having some trouble communicating. Is that > something infecting this email list? :) > > Making "conjugate(log(x)) = log(conjugate(x)) for all x" is trivial > so long as it is treated symbolically: the 'conjugate' operation is > just defined to rewrite itself (auto-simplify) when applied to any > operand of the form log(_), so 'conjugate(log(_))' is evaluated as > 'log(conjugate(_))', where _ stands for any element of the domain > Expression. This is what I meant when I said it was considered true > by definition, i.e. by definition of the symbolic 'conjugate' > operation. Exactly the same sort of thing happens when the > 'conjugate' operation acts on 'conjugate' so that > 'conjugate(conjugate(x))' is simply rewritten as 'x'. Sure, on this level you can implement it. I was thinking on a deeper level, i.e. imagining putting a number x=-1 in and see how could this be true: conjugate(log(-1)) = log(conjugate(-1)) The answer that I was looking for is this: LHS: conjugate(log(-1)) = conjugate(i*pi + 2*pi*i*n) = -i*pi-2*pi*i*n RHS: log(conjugate(-1)) = log(-1) = i*pi + 2*pi*i*m If we pick n=-m-1, we always get LHS=RHS, so the two infinite set of multivalues are equivalent, and the relation conjugate(log(-1)) = log(conjugate(-1)) holds. When you evaluate log(-1), you cannot just give i*pi, you need to give all the multivalues. But otherwise it works. > >> I have provided all the details of the algorithm (B). In approach (B), >> it is not true that >> conjugate(log(x)) = log(conjugate(x)) for all x. >> >> This equation (when conjugate(log(x)) = log(conjugate(x)) holds) >> started this whole discussion. > > That > > log(a*b) = log(a) + log(b) > > is considerably less trivial that the case of 'conjugate'. From my > point of view that is what actually started this branch of the > "fabric" of this discussion. That is where 'normalize' comes in. I think the above answers both, it all works and is consistent in the approach (A). You just need to remember that if a function is multivalued, e.g. log(z), then you always need to enumerate all the values and prove that the LHS is equivalent to RHS. There is a theorem, that says that actually, if you give me a complex function values on just one branch, I can reconstruct the function in all branches. So it is probably the case that you only need to find one set of "n", "m" and "k" to satisfy the equation and it will then hold for the other values as well. But for clarity, I always prove it for all values. > >> So I was trying to understand your approach how to make this hold >> for all "x", and I suggested various ways how maybe it could be >> implemented, and to most of it you said "that's not how FriCAS does >> it". At this point I don't have any more ideas how it could be done, >> so I don't know how to implement
[sage-devel] Re: What are we unable to do right now ?
What we still don't have is a working windows version. This is still a big blocker for being succesfull. On Friday, December 5, 2014 8:17:44 AM UTC+1, Nathann Cohen wrote: > > Helloo everybody ! > > I am preparing some Sage talk, and I wanted to say at some point: > "Honestly we are not that good. We have strong points but we miss many > things too. It all depends on what the developpers are interested in: we > are great on some research areas, and under water level on others" > > Somehow this question is also related to William's "Sage has failed", as > we cannot be a replacement for Mathematica/Maple/ unless we cover all > kinds of mathematics. > > In your past experiences (possibly when using Sage to teach in a > classroom), in which areas do you think we are behind users' expectations ? > > If we had such a list, we could even start asking people around "Do you > work on X ? Cool, we need your help for something big". We could also have > a list of such domains on our website, and do some (cheap) propaganda like: > > "Sage as in 'Free Beer': if you can help us develop Sage's features in the > areas above, we owe you one. Actually we owe you many. Become a contributor > and be rewarded with a free beer from every Sage developper you will meet > around the world" > > We have to know what we cannot do. So let's make a list. > > Nathann > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] User Survey
Hi! Since William's statement, that Sage failed as a real alternative to the 4 MMs there are currently some threads with thoughts on improving Sage. But till now I see only discussions among the devlopers. But I think we should also ask the users. The most of us here are scientists. But to make Sage successful we have to be more considerate about a big block of non mathematicians and beginners, which are a big portion of potential users. I don't think that the functionality of Sage is the big problem, in fact Sage has a great features for zero cost. A bigger problem is that Sage is lacking good 'user experience'. This starts already with installation. We still don't have a good Windows version, and you can't install Sage from the standard repos of your favorite distribution. SageMathCloud overcomes some of these problems by providing an out of the box we interface, but there are still people who want something to install on their hard drive. Especially If they don't want to go online for security reasons, or want to use their own hardware. Additionally it often appears to me that sage lacks of clean design. So I ask: Are there any serious attempts to analyze standard user needs more systematically? (And I don't talk about bug reports) I didn't find any except for a survey from 2009. I think it is very important to get at least some clues about 1. What do most need people for their daily needs 2. How well does these standard tasks work. I give an example from my personal experience: Many people have purely numerical tasks with little symbolics involved (classical in engineering) so they will use much of numpy functionality. If they use Sage then they often will get annoyed by the preparser not handling numpy/scipy well. I know at least 3 people, which switched to IPython+Sympy because of that reason. Not because Sage isn't worse, but some things don't go along very well. A keen Sage user now would simply turn the preparser off. And that would be the answer. This may seem quite trivial to developers which work on far harder topics and are good programmers. Personally I don't have problems tinkering around a bit. But 'normal' people will 1. not read the docu, simply want that it works out of the box 2. not ask for support Most users simply want to input some formulas and want the problem be solved quite elegantly, The feeling is very important. So what can we do? We have to ask the users! In the information age it shouldn't be such a big deal to make some standard surveys on SageMathCloud and Sagemath.org. Of course a short one. Another good start would be make some simple standard tasks as an excercise sheet for students which don't know Sage (e.g. first training session in a math course using sage). Then let the students solve them on their own, and finally let them fill in a form, what they liked and what not, what was difficult, what easy. I know the most of the developers are scientists, and don't care much about good 'marketing'. But think of Henry Ford: He didn't built the best cars the automotif sector t his time, but he gave people what they needed, and hence was successful. I hope I made my concerns clear. Best regards, Stefan -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
> > I am confused. How can fricas outperform mathematica if it is only suited > for elementary integration? I meant the term in the technical sense: http://en.wikipedia.org/wiki/Nonelementary_integral As far as I know (but I may well be mistaken, I'm not an expert in this area), FriCAS has the most complete implementation of the Risch algorithm. This means, besides bugs and nonimplemented branches, if FriCAS cannot do the integral, this is a proof that it has no elementary solution. Beware however, that it has bugs and nonimplemented branches. As I mentioned, Waldek is continuously improving the implementation, which I find quite notable, since it is hard work and hardly recognised. Martin A famous example is integrate(x/sqrt(x^4+10*x^2+-96*x-71),x) which Mathematica won't do, although it is elementary, i.e., has a solution in terms of elementary functions: log((x^6+15*x^4+-80*x^3+27*x^2+-528*x+781)*(x^4+10*x^2+-96*x+-71)^(1/2)+(x^8 +20*x^6+-128*x^5+54*x^4+-1408*x^3+3124*x^2+10001))/8 -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
I am confused. How can fricas outperform mathematica if it is only suited for elementary integration? -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: Mention of Sage in a book review
Nice arcticle! I totally agree with his comments about Matlab. It was written as fast Fortran interface and still has this feeling. Object oriented programming is a joke in Matlab. I used Matlab 2009 and measured 1ms(!) time for access to one simple class member. (Comparison: Pyton needs some µs) I have to laugh if they sell OO programming courses in Matlab ... On Friday, December 5, 2014 11:13:26 AM UTC+1, John Cremona wrote: > > In the review http://newsletter.lms.ac.uk/coffee-love-and-matrix-algebra/ > by Robin Whitty of a novel called "Coffee, love and matrix algebra" > by Gary Ernest Davis there is a nice mention of Sage; though clearly > not in the book itself which seems to be loaded with product > placements for alpha and others. > > John > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
On 2014-12-05, Travis Scrimshaw wrote: > --=_Part_1543_1865320583.1417795602964 > Content-Type: multipart/alternative; > boundary="=_Part_1544_1476759575.1417795602965" > > --=_Part_1544_1476759575.1417795602965 > Content-Type: text/plain; charset=UTF-8 > > Hey Dima, > >>> some pedestrian-level representation theory of associative algebras >> > >> > Do you mean stuff like representations of path algebras (which are >> > highly non-commutative associative algebras)? Minimal projective >> > resolutions of basic algebras? I'm currently working on that. >> >> no, I meant finite-dimensional associative algebras, say defined >> by matrix generators or structure constants. (I mostly care for char=0 >> case here). >> E.g. Magma can compute their absolutely irreducibe representations, >> at least for certain fields like number fields. >> > > Is there a reference for how to construct these irreps? We have > finite-dimensional matrix algebras whose multiplication is given by > matrices. I have code for finite-dimensional Lie algebras given by > structure coefficients that could easily be expanded to cover algebras (and > infinite dimensional). http://www.ams.org/mathscinet-getitem?mr=2879232 I'd be quite surprised if you can do what they do by other means. It depends upon ability to compute nonabelian maximal orders. Dima -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
Am Freitag, 5. Dezember 2014 17:18:37 UTC+1 schrieb mmarco: > > Can you give some further info about it? Do we have an updated package for > fricas or do we need to install it system-wide? > > I do not have a recent fricas installed, but with the old fricas I have, I can simply do sage: fricas.integrate(x^2,x) 1 3 - x 3 (to get ascii-art), or sage: fricas.integrate(x^2,x).unparsed_input_form() '(1/3)*x^3' (Just to make sure: you have to keep in mind that fricas is good only for "elementary" integration.) Martin -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] About SSLv3 security hole
Hi Jori, Please test the fix and report back here: sagenb-0.11.1-py2.7.egg/sagenb/notebook/run_notebook.py: > ssl_context = SSL.Context(SSL.SSLv23_METHOD) > > to > > ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLSv1) > Regards, Jan On 5 December 2014 at 15:21, Volker Braun wrote: > SSLv3 has been obsolete this entire millennium ;-) > > On Friday, December 5, 2014 1:16:15 PM UTC, kcrisman wrote: >> >> We can do this if need be, assuming we have the right stuff. Can someone >>> explain to me what the drawbacks would be? (E.g., Volker seems to indicate >>> that IE6 can only use SSL, not TLS, as does Wikipedia - see >>> https://www.modern.ie/en-us/ie6countdown for an amusing graphic for >>> this.) Does that mean we wouldn't be using openssl >>> >> > It means that you can't use notebook(secure=True) with IE6. Not that it > would be secure if you were able to serve the notebook over ssl. > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. > -- .~. /V\ Jan Groenewald /( )\www.aims.ac.za ^^-^^ -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
Can you give some further info about it? Do we have an updated package for fricas or do we need to install it system-wide? It would be nice to have something like foo.integral(algorithm='fricas') for the cases of integrals that maxima and sympy can't compute. El viernes, 5 de diciembre de 2014 16:35:04 UTC+1, Martin R escribió: > > * Symbolics in general. Symbolic integration and summation. Rewriting >> expressions. Simplifying inequalities. Simplifying expressions subject to >> assumptions involving inequalities. Limits and generalized series >> expansions involving special functions. Sage can do a bit of these things >> via Maxima and SymPy, but it's nowhere near as powerful as Mathematica. >> > > What concerns indefinite symbolic integration, you can use the FriCAS > interface. This outperforms Mathematica, Maple, Maxima and is continuously > improved on by Waldek Hebisch. > > Martin > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Running Sage.app installed by another user
Under OSX Yosemite, I try to install Sage 6.4.1 app in the system applications. When I run sage as admin, everything works fine. However, when my users try to run Sage, they get a warning that they are trying to execute Sage from a read-only filesystem. My question is : It it safe to execute Sage.app if it's installed by the admin? If so, how do I suppress the warning? If not, what can I do? I can't really start installing a the whole Sage in each of my users personal space Thank you, Jerome Tremblay LaCIM, UQAM -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
Hey Dima, >> some pedestrian-level representation theory of associative algebras > > > > Do you mean stuff like representations of path algebras (which are > > highly non-commutative associative algebras)? Minimal projective > > resolutions of basic algebras? I'm currently working on that. > > no, I meant finite-dimensional associative algebras, say defined > by matrix generators or structure constants. (I mostly care for char=0 > case here). > E.g. Magma can compute their absolutely irreducibe representations, > at least for certain fields like number fields. > Is there a reference for how to construct these irreps? We have finite-dimensional matrix algebras whose multiplication is given by matrices. I have code for finite-dimensional Lie algebras given by structure coefficients that could easily be expanded to cover algebras (and infinite dimensional). Hey Nathann, - We currently do not have native support for Lie algebras and quantum groups (although these can be accessed through GAP), but I'm working on this. (Although we do have some support for representations of Kac-Moody Lie algebras (over CC) through crystals.) IDK if other M's have support for these, but I think could support better: - General CW or cubical complexes. Our simplicial complexes are okay, but could likely be improved as well. Actually, I don't think there's much code for algebraic topology... - There are no infinite chain complexes implemented in Sage (with this we could potentially help the previous point). - Knot theory (but is being worked on). - Probability theory, on finite sets in particular, or at least having things phrased like how I learned it in classes (like random variables, distributions, etc.) Best, Travis -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
> > * Symbolics in general. Symbolic integration and summation. Rewriting > expressions. Simplifying inequalities. Simplifying expressions subject to > assumptions involving inequalities. Limits and generalized series > expansions involving special functions. Sage can do a bit of these things > via Maxima and SymPy, but it's nowhere near as powerful as Mathematica. > What concerns indefinite symbolic integration, you can use the FriCAS interface. This outperforms Mathematica, Maple, Maxima and is continuously improved on by Waldek Hebisch. Martin -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: Have I destroyed my git repository?
Answering my own post...
On 2014-12-05, Simon King wrote:
> Traceback (most recent call last):
> File "/home/king/bin/git-trac", line 18, in
> cmdline.launch()
> File "/home/king/Sage/git/git-trac-command/git_trac/cmdline.py", line 206,
> in launch
> app.pull(args.ticket_or_branch)
> File "/home/king/Sage/git/git-trac-command/git_trac/app.py", line 73, in
> pull
> self.repo.pull(remote)
> File "/home/king/Sage/git/git-trac-command/git_trac/git_repository.py",
> line 174, in pull
> self.git.echo.merge('FETCH_HEAD')
> File "/home/king/Sage/git/git-trac-command/git_trac/git_interface.py", line
> 341, in meth
> return self.execute(git_cmd, *args, **kwds)
> File "/home/king/Sage/git/git-trac-command/git_trac/git_interface.py", line
> 98, in execute
> popen_stderr=subprocess.PIPE)
> File "/home/king/Sage/git/git-trac-command/git_trac/git_interface.py", line
> 263, in _run
> raise GitError(result)
> git_trac.git_error.GitError
> Can you give me an advice how to fix it?
It helped to delete the local branch and then do "git trac checkout
15820". Can we do anything to have a useful error message instead of
just saying that there was GitError? I got scared by the above, and I
guess other users would be scared as well.
Best regards,
Simon
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Re: [sage-devel] What are we unable to do right now ?
> > - Generating functions. Start from an equation like > f(t) = sin(t) f'(t) + 1 >and then get information about f (behavior at infinity ? where are > the poles in the complex plane ? what are the coefficients of the > serie expansion ? what is there growth rate ?). There is a well known > maple package for that called gfun which is very powerful. > There are a few different things to do here: 1) generating functions themselves, series expansions: this mainly depends on #16137 (hint, hint!) 2) closure properties of D-algebraic, D-finite, algebraic, rational functions and guessing: a lot of this was recently contributed by the Ore-package 3) asymptotics. Martin -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
> > > * Many numerical functions do not work with arbitrary precision. In > Mathematica and Maple, arbitrary precision works seamlessly pretty much > everywhere. In Sage, a lot of functions are hardcoded for double precision. > A first step would be to provide really solid support for basic numerical > calculus (like computing integrals, #8321) by leveraging what's available > in Pari and mpmath. When it comes to things like multivariate optimization, > solving ODEs and PDEs, etc. with arbitrary precision, I don't think there's > any open source software that competes with Mathematica. > About solving ODE's numerically with high precision, we have recently added an optional TIDES package (which is a state of the art library for this kind of thing), together with an interface to it. Take a look at: http://www.sagemath.org/doc/reference/calculus/sage/calculus/desolvers.html#sage.calculus.desolvers.desolve_tides_mpfr > > * Performance. You often run into a wall as soon as you do anything > slightly complicated in Sage that isn't directly wrapping the right > C/C++/Cython implementation. Bill Hart had an example of computing a > resultant of two large (but not astronomically large) multivariate > polynomials over a finite field, where Magma does it in a minute, Bill's > Julia code does it in 5 seconds, and he had to kill Sage after waiting for > hours... > > Fredrik > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Have I destroyed my git repository?
Hi!
I had accidentally launched "git checkout master" and aborted with
ctrl-C beforeit has finished. Possibly this was a bad bad idea, because
when I now do
git trac pull
on my branch for #15820, I get
remote branch: u/jdemeyer/ticket/15820
Von git://trac.sagemath.org/sage
* branchu/jdemeyer/ticket/15820 -> FETCH_HEAD
Traceback (most recent call last):
File "/home/king/bin/git-trac", line 18, in
cmdline.launch()
File "/home/king/Sage/git/git-trac-command/git_trac/cmdline.py", line 206, in
launch
app.pull(args.ticket_or_branch)
File "/home/king/Sage/git/git-trac-command/git_trac/app.py", line 73, in pull
self.repo.pull(remote)
File "/home/king/Sage/git/git-trac-command/git_trac/git_repository.py", line
174, in pull
self.git.echo.merge('FETCH_HEAD')
File "/home/king/Sage/git/git-trac-command/git_trac/git_interface.py", line
341, in meth
return self.execute(git_cmd, *args, **kwds)
File "/home/king/Sage/git/git-trac-command/git_trac/git_interface.py", line
98, in execute
popen_stderr=subprocess.PIPE)
File "/home/king/Sage/git/git-trac-command/git_trac/git_interface.py", line
263, in _run
raise GitError(result)
git_trac.git_error.GitError
Can you give me an advice how to fix it?
Best regards,
Simon
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Re: [sage-devel] What are we unable to do right now ?
On Friday, December 5, 2014 2:05:24 PM UTC+1, kcrisman wrote: > > http://trac.sagemath.org/wiki/symbolics has it all >> > > Have you been updating that? > Only the areas where I'm active at the moment, functions and series. > Any other broad categories? > I've been updating http://trac.sagemath.org/wiki/algebra too, which looks pretty blue as well. Regards, -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: trac internal error
THaanks for having fixed that ! My ticket is as good as new ! :-P Nathann On Friday, December 5, 2014 5:54:44 PM UTC+5:30, Dima Pasechnik wrote: > > same stuff for me on > http://trac.sagemath.org/ticket/17426#trac-add-comment > Trac detected an internal error: > OSError: [Errno 2] No such file or directory: '/tmp/tmpDFyyXx' > > I guess, we've ran out of space at least on /tmp > > On 2014-12-05, Ralf Stephan > wrote: > > --=_Part_78_1283626907.1417772904986 > > Content-Type: multipart/alternative; > > boundary="=_Part_79_296708187.1417772904986" > > > > --=_Part_79_296708187.1417772904986 > > Content-Type: text/plain; charset=UTF-8 > > > > *Trac detected an internal error:* > > > > OSError: [Errno 2] No such file or directory: '/tmp/tmpAHicED' > > > > There was an internal error in Trac. It is recommended that you notify > your > > local Trac administrator with the information needed to reproduce the > issue. > > > > To that end, you could a ticket. > > > > The action that triggered the error was: > > > > GET: /ticket/16203 > > > > > > Could someone please have a look at this? > > > > > > Regards. > > > > > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] About SSLv3 security hole
SSLv3 has been obsolete this entire millennium ;-) On Friday, December 5, 2014 1:16:15 PM UTC, kcrisman wrote: > > We can do this if need be, assuming we have the right stuff. Can someone >> explain to me what the drawbacks would be? (E.g., Volker seems to indicate >> that IE6 can only use SSL, not TLS, as does Wikipedia - see >> https://www.modern.ie/en-us/ie6countdown for an amusing graphic for >> this.) Does that mean we wouldn't be using openssl >> > It means that you can't use notebook(secure=True) with IE6. Not that it would be secure if you were able to serve the notebook over ssl. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] About SSLv3 security hole
> > > I agree with forcing always TLS in the notebook, screw IE6. > > sagenb-0.11.1-py2.7.egg/sagenb/notebook/run_notebook.py: >> ssl_context = SSL.Context(SSL.SSLv23_METHOD) >> >> to >> >> ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLSv1) >> > > > We can do this if need be, assuming we have the right stuff. Can someone explain to me what the drawbacks would be? (E.g., Volker seems to indicate that IE6 can only use SSL, not TLS, as does Wikipedia - see https://www.modern.ie/en-us/ie6countdown for an amusing graphic for this.) Does that mean we wouldn't be using openssl, or just a different package in it, or ... ? I am not too familiar with this stuff, but reading the Python docs linked it looks like we wouldn't have to do much else than this until we upgrade. (Is that a ticket?) -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] What are we unable to do right now ?
> > >> > In your past experiences (possibly when using Sage to teach in a >> > classroom), in which areas do you think we are behind users' >> expectations ? >> I think the worst is symbolic stuff in general. >> > +5 > > http://trac.sagemath.org/wiki/symbolics has it all > Have you been updating that? My recollection is that it hadn't been that often (I add stuff occasionally), but if you are that would be awesome. Of course there are the links there to the lists of symbolic/calculus tickets. I think I can already summarize this thread in three sentences, which I will 'spin' slightly because it's easy to lose perspective :) Nathann, this might be helpful (or not) for you. * I want something fairly exotic to 'basic' users, but crucial to people in my research area/related areas. * Auto-generated documentation is nice, but it would be much much nicer to have someone competent write a coherent reference manual (or add to the existing documentation). * Even though symbolic manipulation is zillions of times easier than it was for anyone until 1980, it doesn't live up to the standards we now expect for computer algebra. Any other broad categories? -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] What are we unable to do right now ?
Hello, Computing the inverse of the identity matrix is not possible. Ok, it works for rings using RingElement class for the elements (like ZZ, QQ, RR, CC, ...). sage: SF = SymmetricFunctions(QQ).schur(); SF Symmetric Functions over Rational Field in the Schur basis sage: one = SF.one() sage: zero = SF.zero() sage: M = Matrix([[one, zero], [zero, one]]) sage: M [s[] 0] [ 0 s[]] sage: M.det() s[] sage: M.is_invertible() True sage: M.inverse() ... AttributeError: 'SymmetricFunctionAlgebra_schur_with_category' object has no attribute 'fraction_field' sage: M = Matrix([[one]]) ... AttributeError: 'tuple' object has no attribute 'parent' sage: M*M [s[] 0] [ 0 s[]] sage: SteenrodAlgebra(7) mod 7 Steenrod algebra, milnor basis sage: A = SteenrodAlgebra(7) sage: M = Matrix([[A.one(), A.zero()], [A.zero(), A.one()]]) sage: M^2 [1 0] [0 1] sage: M.inverse() AttributeError: 'SteenrodAlgebra_generic_with_category' object has no attribute 'fraction_field' For the curious, defining a fraction_field for these rings is not enought. The good fix should be more serious than that. More generally, there is no any linear algebra in Sage for general rings. As I worked (the last 6 months) around the coinvariants of the symmetric group (with a module of rank n! over the symmetric polynomials in n variables), I only work locally on my machine with a hard hack that breaks linear algebra over classical rings. I REALLY do not know how to fix that... ( see http://trac.sagemath.org/ticket/15160 for curious people, the fix proposed in attachment breaks scalar multiplication for vector whose element use RingElement class, so it breaks Sage horribly... ). Sage is able to model impressively my ring as an abstract free module over the symmetric functions with 5 different bases (Parent with multiples realizations : Harmonic polynomials, Schubert polynomials, Descents monomials, monomials under the staircase and higher Specht polynomials are the available bases). I have most of basis changes implemented on my machine but I do need my hack for inverse the coercions between these bases (since inverting a matrix with unital determinant over general ring need a fix). I am ok with the fact that such a bug concerns only people working with exotic rings or people needing to defined their own rings (like in algebraic combinatorics, we do need vectors spaces indexed by anything). My problems can't be easily translated as problem of linear algebra over QQ. Cheers, Nicolas B. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: Please fix trac...
Fixed On Friday, December 5, 2014 12:35:08 PM UTC, Dima Pasechnik wrote: > > it's apparently out of space on /tmp > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Re: What are we unable to do right now ?
On Fri, 5 Dec 2014, Fredrik Johansson wrote: Another weakness of the Sage reference manual is that the doctest examples only show text output -- the Ma's examples often show graphical output, which can be a great help. Having this would be very, very, very nice thing to have! For many poset functions it would make written explanation almost unneeded. -- Jori Mäntysalo
Re: [sage-devel] Re: What are we unable to do right now ?
On Friday, December 5, 2014 1:08:14 PM UTC+1, Jori Mantysalo wrote: > > > Having documentation arranged by technical implementation is also bad. > Having TESTS-section shown for normal user is bad. Having is_lattice() on > different page that is_meet_semilattice() is bad. > Seconding this. Mixing tests and documentation has its benefits, but it also severely reduces the signal-to-noise ratio for non-developers. In most sections of the Sage reference manual, there is no preamble explaining the mathematical context, and no indication of what the most important methods are (it can be hard for the user to find the right method in an alphabetical list that spans several pages). The structure is sometimes strange: for example, "Solving ODE numerically by GSL" is listed under "Symbolic Calculus"... and on the other hand "Numerical Optimization" is listed under "Miscellaneous Mathematics". Maple/Mathematica/Matlab generally do a better job of grouping functions logically by subject area, listing *relevant* examples, and allowing the user to find related methods easily. Another weakness of the Sage reference manual is that the doctest examples only show text output -- the Ma's examples often show graphical output, which can be a great help. Fredrik -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Please fix trac...
it's apparently out of space on /tmp -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
On 2014-12-05, Fredrik Johansson wrote: > --=_Part_1821_492426932.1417781508772 > Content-Type: multipart/alternative; > boundary="=_Part_1822_1964954233.1417781508772" > > --=_Part_1822_1964954233.1417781508772 > Content-Type: text/plain; charset=UTF-8 > > On Friday, December 5, 2014 8:17:44 AM UTC+1, Nathann Cohen wrote: >> >> Helloo everybody ! >> >> I am preparing some Sage talk, and I wanted to say at some point: >> "Honestly we are not that good. We have strong points but we miss many >> things too. It all depends on what the developpers are interested in: we >> are great on some research areas, and under water level on others" >> >> Somehow this question is also related to William's "Sage has failed", as >> we cannot be a replacement for Mathematica/Maple/ unless we cover all >> kinds of mathematics. >> >> In your past experiences (possibly when using Sage to teach in a >> classroom), in which areas do you think we are behind users' expectations ? >> > > * Symbolics in general. Symbolic integration and summation. Rewriting > expressions. Simplifying inequalities. Simplifying expressions subject to > assumptions involving inequalities. Limits and generalized series > expansions involving special functions. Sage can do a bit of these things > via Maxima and SymPy, but it's nowhere near as powerful as Mathematica. > > * Many numerical functions do not work with arbitrary precision. In > Mathematica and Maple, arbitrary precision works seamlessly pretty much > everywhere. In Sage, a lot of functions are hardcoded for double precision. > A first step would be to provide really solid support for basic numerical > calculus (like computing integrals, #8321) by leveraging what's available > in Pari and mpmath. When it comes to things like multivariate optimization, > solving ODEs and PDEs, etc. with arbitrary precision, I don't think there's > any open source software that competes with Mathematica. The latter is not that uniformly bad. E.g. Sage beats the MMas on arbitrary precision linear optimisation :-) Asn well, there are OSS's, not (yet) in Sage, that do arbitrary precision semidefinite optimisation (a particular kind of convex optimisation, generalising linear) something that the MMas don't do. Dima > > * Performance. You often run into a wall as soon as you do anything > slightly complicated in Sage that isn't directly wrapping the right > C/C++/Cython implementation. Bill Hart had an example of computing a > resultant of two large (but not astronomically large) multivariate > polynomials over a finite field, where Magma does it in a minute, Bill's > Julia code does it in 5 seconds, and he had to kill Sage after waiting for > hours... > > Fredrik > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: trac internal error
same stuff for me on http://trac.sagemath.org/ticket/17426#trac-add-comment Trac detected an internal error: OSError: [Errno 2] No such file or directory: '/tmp/tmpDFyyXx' I guess, we've ran out of space at least on /tmp On 2014-12-05, Ralf Stephan wrote: > --=_Part_78_1283626907.1417772904986 > Content-Type: multipart/alternative; > boundary="=_Part_79_296708187.1417772904986" > > --=_Part_79_296708187.1417772904986 > Content-Type: text/plain; charset=UTF-8 > > *Trac detected an internal error:* > > OSError: [Errno 2] No such file or directory: '/tmp/tmpAHicED' > > There was an internal error in Trac. It is recommended that you notify your > local Trac administrator with the information needed to reproduce the issue. > > To that end, you could a ticket. > > The action that triggered the error was: > > GET: /ticket/16203 > > > Could someone please have a look at this? > > > Regards. > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
On Friday, December 5, 2014 8:17:44 AM UTC+1, Nathann Cohen wrote: > > Helloo everybody ! > > I am preparing some Sage talk, and I wanted to say at some point: > "Honestly we are not that good. We have strong points but we miss many > things too. It all depends on what the developpers are interested in: we > are great on some research areas, and under water level on others" > > Somehow this question is also related to William's "Sage has failed", as > we cannot be a replacement for Mathematica/Maple/ unless we cover all > kinds of mathematics. > > In your past experiences (possibly when using Sage to teach in a > classroom), in which areas do you think we are behind users' expectations ? > * Symbolics in general. Symbolic integration and summation. Rewriting expressions. Simplifying inequalities. Simplifying expressions subject to assumptions involving inequalities. Limits and generalized series expansions involving special functions. Sage can do a bit of these things via Maxima and SymPy, but it's nowhere near as powerful as Mathematica. * Many numerical functions do not work with arbitrary precision. In Mathematica and Maple, arbitrary precision works seamlessly pretty much everywhere. In Sage, a lot of functions are hardcoded for double precision. A first step would be to provide really solid support for basic numerical calculus (like computing integrals, #8321) by leveraging what's available in Pari and mpmath. When it comes to things like multivariate optimization, solving ODEs and PDEs, etc. with arbitrary precision, I don't think there's any open source software that competes with Mathematica. * Performance. You often run into a wall as soon as you do anything slightly complicated in Sage that isn't directly wrapping the right C/C++/Cython implementation. Bill Hart had an example of computing a resultant of two large (but not astronomically large) multivariate polynomials over a finite field, where Magma does it in a minute, Bill's Julia code does it in 5 seconds, and he had to kill Sage after waiting for hours... Fredrik -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: How to avoid duplicate work when merging?
Hi Volker, On 2014-12-05, Volker Braun wrote: > Should work. Perhaps one of the edits in C conflicted with the resolution? Possibly there is a conflict in some hunks, and of course I don't complain to resolve these. However, "git mergetool" then asked me to resolve *all* hunks, including those that I had resolved before. > You can also try different conflict resolution strategies (man git-merge) Thanks! Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Re: What are we unable to do right now ?
Factorization of multivariate polynomials on ZZ is not possible. Actually it is, but you have to convert them to QQ first. And for beginner this kind of things are obstacles. * * * I think that also error reporting is not optimal for most users, and horror for beginner. It should be something like "Error: Unclosed '['. Did you forget ']'?" Or why do I get SyntaxError from "1 + 2"? I just copied it from a document, where happens to be non-breaking space (U+00A0). How make this happen, that I don't know. * * * Having documentation arranged by technical implementation is also bad. Having TESTS-section shown for normal user is bad. Having is_lattice() on different page that is_meet_semilattice() is bad. * * * The fact that I like Sage does not mean that I don't also hate it. -- Jori Mäntysalo
[sage-devel] Re: How to avoid duplicate work when merging?
Should work. Perhaps one of the edits in C conflicted with the resolution? You can also try different conflict resolution strategies (man git-merge) On Friday, December 5, 2014 11:50:40 AM UTC, Simon King wrote: > > Hi Volker, > > On 2014-12-05, Volker Braun > wrote: > > On Friday, December 5, 2014 11:16:34 AM UTC, Simon King wrote: > >> > >> Moreover, there are merge conflicts. Hence, they *have* to be > >> resolved at some point. > >> > > > > Yes, but they only need to be resolved once if you wait. Eventually > there > > will be a conflict with the develop branch that you need to resolve. But > if > > all merges are with the develop branch then all future merges see the > > resolution in their history, so you don't have to re-do them. > > Is that special to the develop branch? After all, when I merge A' into B > (resulting in B') and then merge B' into C, then the history of B' does > contain the resolution, isn't it? That's exactly why I am surprised of > the fact that I need to recreate the resolution when merging B' into C. > > Best regards, > Simon > > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: How to avoid duplicate work when merging?
Hi Volker, On 2014-12-05, Volker Braun wrote: > On Friday, December 5, 2014 11:16:34 AM UTC, Simon King wrote: >> >> Moreover, there are merge conflicts. Hence, they *have* to be >> resolved at some point. >> > > Yes, but they only need to be resolved once if you wait. Eventually there > will be a conflict with the develop branch that you need to resolve. But if > all merges are with the develop branch then all future merges see the > resolution in their history, so you don't have to re-do them. Is that special to the develop branch? After all, when I merge A' into B (resulting in B') and then merge B' into C, then the history of B' does contain the resolution, isn't it? That's exactly why I am surprised of the fact that I need to recreate the resolution when merging B' into C. Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: How to avoid duplicate work when merging?
On Friday, December 5, 2014 11:16:34 AM UTC, Simon King wrote: > > Moreover, there are merge conflicts. Hence, they *have* to be > resolved at some point. > Yes, but they only need to be resolved once if you wait. Eventually there will be a conflict with the develop branch that you need to resolve. But if all merges are with the develop branch then all future merges see the resolution in their history, so you don't have to re-do them. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
Hi Simon, On 2014-12-05, Simon King wrote: > On 2014-12-05, Dima Pasechnik wrote: >> some pedestrian-level representation theory of associative algebras > > Do you mean stuff like representations of path algebras (which are > highly non-commutative associative algebras)? Minimal projective > resolutions of basic algebras? I'm currently working on that. no, I meant finite-dimensional associative algebras, say defined by matrix generators or structure constants. (I mostly care for char=0 case here). E.g. Magma can compute their absolutely irreducibe representations, at least for certain fields like number fields. > >> support for sparse matrices over R and C is lacking in a big way >> (and in general sparse matrices are very slow etc;) > > +1. Sparse matrices are quite important, among others for implementing > Faugère algorithms to compute Gröbner bases. I have a plan to enable sparse matrices for RDF and CDF via cvxopt, which are quite good there. But that's only for these fields. Dima -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: How to avoid duplicate work when merging?
Hi Volker, On 2014-12-05, Volker Braun wrote: > On Friday, December 5, 2014 9:13:12 AM UTC, Simon King wrote: >> >> would result in resolving the same conflicts twice. Certainly there is a >> better way!?! >> > > Don't merge branches unless you have to. I have to. A is a dependency for B, B is a dependency of C, and A' changes some function names that A introduced---and that are used in B and C. Moreover, there are merge conflicts. Hence, they *have* to be resolved at some point. > The easiest solution is just to not merge A' into B No way, I need to cope with the non-trivial changes in the dependencies. > The feature you are asking for is git rerere "reuse recorded resolution", > http://git-scm.com/blog/2010/03/08/rerere.html Thanks, I'll have a look. Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
Hi Dima, On 2014-12-05, Dima Pasechnik wrote: > some pedestrian-level representation theory of associative algebras Do you mean stuff like representations of path algebras (which are highly non-commutative associative algebras)? Minimal projective resolutions of basic algebras? I'm currently working on that. > support for sparse matrices over R and C is lacking in a big way > (and in general sparse matrices are very slow etc;) +1. Sparse matrices are quite important, among others for implementing Faugère algorithms to compute Gröbner bases. Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: How to avoid duplicate work when merging?
On Friday, December 5, 2014 9:13:12 AM UTC, Simon King wrote: > > would result in resolving the same conflicts twice. Certainly there is a > better way!?! > Don't merge branches unless you have to. The easiest solution is just to not merge A' into B Also, commits are immutable: Merging A' into B means: make a new branch head B'. It doesn't change B nor anything in the history of C. The feature you are asking for is git rerere "reuse recorded resolution", http://git-scm.com/blog/2010/03/08/rerere.html -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] About SSLv3 security hole
There is no Python 2.7.9 yet, this is upstream WIP. I agree with forcing always TLS in the notebook, screw IE6. On Friday, December 5, 2014 7:49:52 AM UTC, Jan Groenewald wrote: > > sagenb-0.11.1-py2.7.egg/sagenb/notebook/run_notebook.py: > ssl_context = SSL.Context(SSL.SSLv23_METHOD) > > to > > ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLSv1) > +1 -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Mention of Sage in a book review
In the review http://newsletter.lms.ac.uk/coffee-love-and-matrix-algebra/ by Robin Whitty of a novel called "Coffee, love and matrix algebra" by Gary Ernest Davis there is a nice mention of Sage; though clearly not in the book itself which seems to be loaded with product placements for alpha and others. John -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
We have very little to work on modules over polynomial rings (no groebner basis, resolutions, etc). -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] trac internal error
Same issue with http://trac.sagemath.org/ticket/16453 -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
Specifically in my opinion, many special functions and polynomials are still not symbolic. This prevents for example implementations of creative telescoping. Regards, -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] trac internal error
*Trac detected an internal error:* OSError: [Errno 2] No such file or directory: '/tmp/tmpAHicED' There was an internal error in Trac. It is recommended that you notify your local Trac administrator with the information needed to reproduce the issue. To that end, you could a ticket. The action that triggered the error was: GET: /ticket/16203 Could someone please have a look at this? Regards. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] What are we unable to do right now ?
On Friday, December 5, 2014 10:18:12 AM UTC+1, Jeroen Demeyer wrote: > > On 2014-12-05 08:17, Nathann Cohen wrote: > > In your past experiences (possibly when using Sage to teach in a > > classroom), in which areas do you think we are behind users' > expectations ? > I think the worst is symbolic stuff in general. > +5 http://trac.sagemath.org/wiki/symbolics has it all Regards, -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] Re: What are we unable to do right now ?
On 2014-12-05, Nathann Cohen wrote: > --f46d0438906335ad0d050972df25 > Content-Type: text/plain; charset=UTF-8 > > Helloo everybody ! > > I am preparing some Sage talk, and I wanted to say at some point: "Honestly > we are not that good. We have strong points but we miss many things too. It > all depends on what the developpers are interested in: we are great on some > research areas, and under water level on others" some pedestrian-level representation theory of associative algebras (I already mentioned this a while ago when Anne asked about what they can do witnin their grant project...) support for sparse matrices over R and C is lacking in a big way (and in general sparse matrices are very slow etc;) > > Somehow this question is also related to William's "Sage has failed", as we > cannot be a replacement for Mathematica/Maple/ unless we cover all > kinds of mathematics. > > In your past experiences (possibly when using Sage to teach in a > classroom), in which areas do you think we are behind users' expectations ? > > If we had such a list, we could even start asking people around "Do you > work on X ? Cool, we need your help for something big". We could also have > a list of such domains on our website, and do some (cheap) propaganda like: > > "Sage as in 'Free Beer': if you can help us develop Sage's features in the > areas above, we owe you one. Actually we owe you many. Become a contributor > and be rewarded with a free beer from every Sage developper you will meet > around the world" > > We have to know what we cannot do. So let's make a list. > > Nathann > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] What are we unable to do right now ?
On 2014-12-05 08:17, Nathann Cohen wrote: In your past experiences (possibly when using Sage to teach in a classroom), in which areas do you think we are behind users' expectations ? I think the worst is symbolic stuff in general. My favorite example: Sage cannot solve x == sqrt(x): sage: solve(x == sqrt(x), x) [x == sqrt(x)] -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
[sage-devel] How to avoid duplicate work when merging?
Hi! Once more, I got annoyed either by git, or by my lacking git skills. At #15820, the reviewer made some changes. There is a follow-up ticket #16453, and I had to resolve conflicts for merging #15820 into #16453. And then, there is a follow-follow-up ticket #17435. When merging #16453 into #17435, I was asked to resolve the same conflicts *again*, even though I had solved them when merging #15820 into #16453. So, given commits A,A',B,C depending like this ...--A--B--C \ A' how can one merge A' into B and C with least effort? At least in the example above, git checkout B git merge A' git mergetool # resolve conflicts git commit -a git checkout C git merge B would result in resolving the same conflicts twice. Certainly there is a better way!?! Side complication: The result of merging A' into B has already been published. Hence, the solution should better not change B's history. Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] What are we unable to do right now ?
Am 05.12.2014 um 08:17 schrieb Nathann Cohen: > In your past experiences (possibly when using Sage to teach in a > classroom), in which areas do you think we are behind users' expectations ? It should be possible to use Sage in 1st year students' math classes. My pet peeve there is solving systems of rational inequalities like "abs(2*x-3)/(3*x)>(x+1)/(x-2) and (4*x+5)^2/(x-3)http://trac.sagemath.org/ticket/14229 and my posts https://groups.google.com/d/msg/sage-devel/QLEFLgkuXRg/DDscOPcouvIJ and https://groups.google.com/d/msg/sage-support/yqzUKxV6dy0/NYMF98lsJzoJ . I know I should try to build a qepcad package for this (http://trac.sagemath.org/ticket/10224) ... Robert -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] What are we unable to do right now ?
Hi Nathann, It would be cool to gather the answers to your thread on the wiki... > In your past experiences (possibly when using Sage to teach in a > classroom), in which areas do you think we are behind users' expectations ? It was in classroom but more for PhD students/researcher. Very far behind expectations were: - Generating functions. Start from an equation like f(t) = sin(t) f'(t) + 1 and then get information about f (behavior at infinity ? where are the poles in the complex plane ? what are the coefficients of the serie expansion ? what is there growth rate ?). There is a well known maple package for that called gfun which is very powerful. - More generally, symbolic computations beyond plotting cos(x) is very limited. - Comparison of algebraic numbers. It is currently not possible to compare two real roots of polynomials (i.e. which one is greater than the other). Hopefully, I will work on this in january at the pari workshop ;-) Vincent -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
Re: [sage-devel] Re: What are we unable to do right now ?
I feel that some plots could be better. I often end up writing pure matplotlib code. For example for histograms, boxplots (current version is limited) etc... On Fri Dec 05 2014 at 07:22:58 Nathann Cohen wrote: > Weird to answer your own thread, but I think that we are bad for plots. > Look at that: > > sage: graphs.RandomTree(40).show() > sage: graphs.RandomTree(40).show(method="js") > > The first one is a picture, the second uses d3.js. You can do a lot of > crazy things with it, and it is done in javascript: > > https://github.com/mbostock/d3/wiki/Gallery > > Anyway. Let us use this thread ot make the list of what is wrong, and we > will try to solve each problem independently in domain-specific threads. > > Nathann > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
