Re: [sage-support] Those cookies again...
On Sat, 21 Aug 2010 19:12:49 -0700 (PDT), kcrisman wrote: > Sysadmin has found possible workaround of deleting history of the > browser. This is fine in a lab, but potentially very crippling for > those of us who rely on auto-completion of often-visited sites. > Sysadmin is also very unlikely to try 4.5.2 VMWare image after recent > reports of it not being so hot, though I think those may have been > exaggerated - and anyhow he has a lot to do with the start of classes. I'd say the only way you will know whether 4.5.2 works for you is to try it out. The vmware image gets downloaded *a lot* (200 times in the first 5 days), and as far as I know there were only two problems reported with it: * unable to access the notebook from the host machine on Windows (this works for me on Mac OS X, and I don't have a Windows machine to test on -- someone suggested a workaround on the list but we haven't heard the original poster confirm that it fixed his problem) * request for having R installed with image support; I will look into this for 4.5.3, but if this is likely to be important to you, you can just install the ubuntu libraries in your copy of the virtual machine So, I'm not saying that the 4.5.2 vmware image is perfect, but I'm not convinced it's any worse than 4.3, and once again, you can find out whether it works for you by trying it out. Try it out on your computer first and see if the cookies issue is fixed, and then see if your system administrator is willing to give it a shot. Best, Alex -- Alex Ghitza -- http://aghitza.org/ Lecturer in Mathematics -- The University of Melbourne -- Australia -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] Re: tab on an iPad
On 8/23/10 1:28 PM, A. Jorge Garcia wrote: I had a problem with SAGE on my iPod Touch. Everything worked fine except for jMol when viewing 3D graphs. jMol requires jre and that is not installed on Safari. Apparently this is a restriction on the iTouch, there's no way to install jre for Safari on iTouch. I've seen it installed on a MacBook Pro, however. If you don't do 3D graphs, I think you're fine. I just don't know if the iPad has the same restrictions as the iTouch Does the iTouch or iPad support WebGL? See https://cvs.khronos.org/svn/repos/registry/trunk/public/webgl/sdk/demos/webkit/SpinningBox.html for example. Thanks, Jason -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
Re: [sage-support] tab on an iPad
yup, I was just alluding to fact that if you use the default viewer
you're
stuck. As you say, you can use Tachyon but then you can't rotate the
3D graphs!
BTW, I know it may sound strange, but I know all about Tachyon as
that's how I
originally discovered SAGE. At the time I was playing with 3D ray
tracers like
Tachyon and povray. I found a video demoing dSAGE running a povray
plot and was
instantly hooked on SAGE. I really should figure out how to distribute
SAGE
jobs over a cluster
Thanx,
A. Jorge Garcia
http://shadowfaxrant.blogspot.com
--
Sent from my Verizon Wireless mobile phone
--Original Message--
From: kcrisman
To: "sage-support"
Date: Mon, Aug 23, 12:04 PM -0700
Subject: [sage-support] Re: tab on an iPad
On Aug 23, 2:28 pm, "A. Jorge Garcia" wrote:
I had a problem with SAGE on my iPod Touch. Everything worked fine
except for jMol when viewing 3D graphs. jMol requires jre and that is
not installed on Safari. Apparently this is a restriction on the
iTouch, there's no way to install jre for Safari on iTouch. I've seen
it installed on a MacBook Pro, however.
If you don't do 3D graphs, I think you're fine. I just don't know if
the iPad has the same restrictions as the iTouch
By the way, 3D graphs *will* work without Java, but you would need to
view them statically.
sage: var('y')
sage: plot3d(x^2 + y^2, (x,-2,2), (y,-2,2),viewer='tachyon')
This is unfortunately buried in the documentation, and not in
sage: plot3d?
- kcrisman
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[sage-support] Re: numerical evaluation
Hi, On 08/23/2010 03:42 PM, robin hankin wrote: > I tried this: > > roots = solve(x^3+10*x^2+11*x+8==0,x) > > The best I can do is > > N(roots[1].rhs()) > > but this is just one at a time. How do I make N() operate on all of roots? You may like for r in roots: print N(r.rhs()) or [N(r.rhs()) for r in roots] Cheers, Jason -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
Re: [sage-support] numerical evaluation
I'm not sure if this helps your situation or not, but if you are
interested in the roots of "f(x)=0", then using roots has a much more
predictable behaviour.
So for example:
sage: expr=(x^3+10*x^2+11*x+8)
sage: expr.roots()
sage: expr.roots(ring=RR)
[(-8.86042628425072, 1)]
sage: expr.roots(ring=CC)
[(-8.86042628425072, 1), (-0.569786857874640 - 0.760417012386730*I, 1),
(-0.569786857874640 + 0.760417012386730*I, 1)]
This way, you're giving just enough hint to SAGE to give you exactly
the answer you are looking for.
Soroosh
On Mon, 23 Aug 2010 20:42:39 +0100
robin hankin wrote:
> Hi
>
> thanks for your earlier answers.
>
> I quite often do this:
>
> sage: solve(x^3 + 10*x^2+11*x+8==0,x)
> [snip]
>
> Then I realize that the analytic solution is rather complicated.
> So I want a numerical approximation.
>
> I tried this:
>
> roots = solve(x^3+10*x^2+11*x+8==0,x)
> sage: roots
> [x == -1/2*(1/3*sqrt(926) - 613/27)^(1/3)*(I*sqrt(3) + 1) -
> 1/18*(-67*I*sqrt(3) + 67)/(1/3*sqrt(926) - 613/27)^(1/3) - 10/3, x ==
> -1/2*(1/3*sqrt(926) - 613/27)^(1/3)*(-I*sqrt(3) + 1) -
> 1/18*(67*I*sqrt(3) + 67)/(1/3*sqrt(926) - 613/27)^(1/3) - 10/3, x ==
> (1/3*sqrt(926) - 613/27)^(1/3) + 67/9/(1/3*sqrt(926) - 613/27)^(1/3) -
> 10/3]
> sage: N(roots)
>
>
> but this returns an error ("too many values to unpack").
>
>
> The best I can do is
>
> N(roots[1].rhs())
>
> but this is just one at a time. How do I make N() operate on all of
> roots? Or is there a much neater way of accomplishing the same thing?
>
> cheers
>
> rksh
>
>
>
>
>
signature.asc
Description: PGP signature
[sage-support] Re: How can I make implicit_multiplication default?
Hi Robert, On 23 Aug., 18:08, Robert Bradshaw wrote: > > ... And on the other hand, I can't see how life with Sage would be > > any easier if automatic_names was the standard. > > Think about someone working through a series of calculus textbook > exercises (mostly one-liners). I didn't deny that there are situations where automatic_names is handy, but I think it wouldn't be good as the default... > Personally, I wouldn't every want it to > be default, ... and see that we agree. > This, and implicit multiplication, should be in the FAQ at least. Certainly +1! Cheers, Simon -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] numerical evaluation
Hi
thanks for your earlier answers.
I quite often do this:
sage: solve(x^3 + 10*x^2+11*x+8==0,x)
[snip]
Then I realize that the analytic solution is rather complicated.
So I want a numerical approximation.
I tried this:
roots = solve(x^3+10*x^2+11*x+8==0,x)
sage: roots
[x == -1/2*(1/3*sqrt(926) - 613/27)^(1/3)*(I*sqrt(3) + 1) -
1/18*(-67*I*sqrt(3) + 67)/(1/3*sqrt(926) - 613/27)^(1/3) - 10/3, x ==
-1/2*(1/3*sqrt(926) - 613/27)^(1/3)*(-I*sqrt(3) + 1) -
1/18*(67*I*sqrt(3) + 67)/(1/3*sqrt(926) - 613/27)^(1/3) - 10/3, x ==
(1/3*sqrt(926) - 613/27)^(1/3) + 67/9/(1/3*sqrt(926) - 613/27)^(1/3) -
10/3]
sage: N(roots)
but this returns an error ("too many values to unpack").
The best I can do is
N(roots[1].rhs())
but this is just one at a time. How do I make N() operate on all of roots?
Or is there a much neater way of accomplishing the same thing?
cheers
rksh
--
Robin Hankin
Uncertainty Analyst
hankin.ro...@gmail.com
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[sage-support] Re: tab on an iPad
On Aug 23, 2:28 pm, "A. Jorge Garcia" wrote:
> I had a problem with SAGE on my iPod Touch. Everything worked fine
> except for jMol when viewing 3D graphs. jMol requires jre and that is
> not installed on Safari. Apparently this is a restriction on the
> iTouch, there's no way to install jre for Safari on iTouch. I've seen
> it installed on a MacBook Pro, however.
>
> If you don't do 3D graphs, I think you're fine. I just don't know if
> the iPad has the same restrictions as the iTouch
>
By the way, 3D graphs *will* work without Java, but you would need to
view them statically.
sage: var('y')
sage: plot3d(x^2 + y^2, (x,-2,2), (y,-2,2),viewer='tachyon')
This is unfortunately buried in the documentation, and not in
sage: plot3d?
- kcrisman
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Re: [sage-support] tab on an iPad
I had a problem with SAGE on my iPod Touch. Everything worked fine except for jMol when viewing 3D graphs. jMol requires jre and that is not installed on Safari. Apparently this is a restriction on the iTouch, there's no way to install jre for Safari on iTouch. I've seen it installed on a MacBook Pro, however. If you don't do 3D graphs, I think you're fine. I just don't know if the iPad has the same restrictions as the iTouch HTH, A. Jorge Garcia http://shadowfaxrant.blogspot.com http://www.youtube.com/calcpage2009 Teacher & Professor Applied Mathematics, Physics & Computer Science Baldwin Senior High School & Nassau Community College -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] tab on an iPad
Although I do most of my sage learning on a Mac, I've been playing around with using it on an iPad though http://www.sagenb.org/. It works fine if I know what I want to type but I can't do completion, for example because there isn't a tab key (I think). Anybody know of a workaround to that? Ken Levasseur UMass Lowell -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
Re: [sage-support] Re: How can I make implicit_multiplication default?
On Mon, Aug 23, 2010 at 9:08 AM, Robert Bradshaw
wrote:
> On Mon, Aug 23, 2010 at 6:54 AM, Simon King wrote:
>> Hi Robin,
>>
>> On 23 Aug., 13:43, robin hankin wrote:
>>> Re automatic_names(): why isn't this the default?
>>>
>>> Now I know it exists, I think I'll probably use it all the time.
>>>
>>> Who uses sage without this option?
>>
>> I find automatic_names horrible, to say the least! In my opinion, such
>> thing should *never ever* be standard!
>>
>> 1. If you write a little program on the command line and it does
>> something, but simply it doesn't do the right thing or you get strange
>> error messages about missing attributes -- it would be very hard to
>> find out that you forgot to define some object X, so that Sage worked
>> in the wrong assumption that X is a symbolic variable. I strongly
>> prefer to get a clear error message, namely "NameError: Name 'X' is
>> not defined" or so.
>>
>> 2. "Explicit is better than implicit" is a quite common credo. I think
>> it is unsafe to rely on implicit assumptions of the type of an object.
>>
>> 3. I hardly ever work with symbolic variables. So, I really don't see
>> the point why "X" should default to a symbolic variable.
>>
>> 4. My impression is that for quite many people a symbolic variable is
>> the first thing that comes to mind when computing in a CAS - and it
>> takes them a long while until they find that for their particular
>> problem a different class (like a polynomial) works much better.
>> Making a symbolic variable the default, I am afraid that one would
>> support the wrong belief that symbolic variables are good for
>> *everything*.
>>
>>
>> So, it is not so much that programs would break. But debugging would
>> be more difficult, and it would teach the people the wrong lesson,
>> IMHO. And on the other hand, I can't see how life with Sage would be
>> any easier if automatic_names was the standard.
>
> Think about someone working through a series of calculus textbook
> exercises (mostly one-liners). Personally, I wouldn't every want it to
> be default, but can see how some people could really find it useful
> (especially as we're aiming to be a viable alternative to the Ma's.
> Also, note that Python itself has implicit variable declaration (as
> opposed to, say, C, etc.) which has its pros and cons (though I like
> it).
>
> This, and implicit multiplication, should be in the FAQ at least.
One more thing--I find it really handy when I'm pasting in expressions
form elsewhere, e.g. a paper or something. However, rather than enable
the options in the preparser and changing the language, I do
sage: SR("x^2 + 2x - 5y")
x^2 + 2*x - 5*y
This string-level implicit multiplication/variable binding for
polynomial rings too:
sage: R = QQ['x']
sage: R("3x^5 - 2x")
3*x^5 - 2*x
- Robert
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Re: [sage-support] Re: How can I make implicit_multiplication default?
On Mon, Aug 23, 2010 at 6:54 AM, Simon King wrote: > Hi Robin, > > On 23 Aug., 13:43, robin hankin wrote: >> Re automatic_names(): why isn't this the default? >> >> Now I know it exists, I think I'll probably use it all the time. >> >> Who uses sage without this option? > > I find automatic_names horrible, to say the least! In my opinion, such > thing should *never ever* be standard! > > 1. If you write a little program on the command line and it does > something, but simply it doesn't do the right thing or you get strange > error messages about missing attributes -- it would be very hard to > find out that you forgot to define some object X, so that Sage worked > in the wrong assumption that X is a symbolic variable. I strongly > prefer to get a clear error message, namely "NameError: Name 'X' is > not defined" or so. > > 2. "Explicit is better than implicit" is a quite common credo. I think > it is unsafe to rely on implicit assumptions of the type of an object. > > 3. I hardly ever work with symbolic variables. So, I really don't see > the point why "X" should default to a symbolic variable. > > 4. My impression is that for quite many people a symbolic variable is > the first thing that comes to mind when computing in a CAS - and it > takes them a long while until they find that for their particular > problem a different class (like a polynomial) works much better. > Making a symbolic variable the default, I am afraid that one would > support the wrong belief that symbolic variables are good for > *everything*. > > > So, it is not so much that programs would break. But debugging would > be more difficult, and it would teach the people the wrong lesson, > IMHO. And on the other hand, I can't see how life with Sage would be > any easier if automatic_names was the standard. Think about someone working through a series of calculus textbook exercises (mostly one-liners). Personally, I wouldn't every want it to be default, but can see how some people could really find it useful (especially as we're aiming to be a viable alternative to the Ma's. Also, note that Python itself has implicit variable declaration (as opposed to, say, C, etc.) which has its pros and cons (though I like it). This, and implicit multiplication, should be in the FAQ at least. - Robert -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] Re: Those cookies again...
Wow, I really didn't expect to open this discussion with that post. > I expect Sage upgrades will slip further down your system admin's priority > list > if they are causing him problems. Though he's actually quite Sage-friendly, and sounds like he'll do it. The only issue was > > I am really hesitant > > to use this in class when I can't even make it work on my own computer > > properly. > > I don't blame you. Though again, I am personally quite likely to just find a way about it, since I've invested so much in Sage. > === From Peter Jeremy === > I am very concerned at this "release it now, we'll make it work later" > mentality. > === > The only possible way Sage might get less buggy, is for more people with > similar > views to me, make them known to William. *Perhaps*, if he realises people like > you are reluctant to use Sage for classes because of the bug rates, he might > do > something to address the quality control issues. > Well, in general it seems to me that most Sage bugs come from things/ functionality that didn't exist before, and once they exist people want to start using them. But unlike a commercial system, the only realistic way we have to look for these bugs is for people to use the system. I just don't see how else to do it; I don't think most Sage developers necessarily use the latest bleeding-edge release for day-to- day stuff. For instance, I have a modified R optional package installed on one of my Sage installs, and since getting that to play nice on every new Sage would be tedious and boring, I just keep sage-4.4.4 on my laptop for research only. Similarly for classroom use - one usually uses the same server all semester, so there isn't opportunity to see *new* bugs. > === > in a suitably complex system there is a certain irreducible number of errors. > Any attempt to fix observed errors tends to result in the introduction of > other > errors > === I think that while there are certainly some bugs that really don't satisfy this, there are plenty of bugfixes that introduce new errors in Sage - it is easily that complex. However, these usually result as a result of uncovering some hitherto non-existent (or possibly non- wrapped) functionality which turns out to have bugs, which will only be uncovered by "real" users. So actually, I find the release early and often mantra to be helpful, because it helps make it better; finding edge cases is much less likely to happen without a full-time team of dedicated staff otherwise. I think that even some randomized test suite is not so likely to find things unless it starts just entering random valid Sage commands, even ones that don't make sense to a "real" user. And I don't think there is a lack of attention to fixing bugs; every release is a bug-fix release. It is also a new-functionality release - which yes, introduces bugs, but not ones that would have even been visible before. - kcrisman -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] Re: Those cookies again...
PS: On 23 Aug., 12:55, Simon King wrote: > ... > My impression is that the Sage development process is quite far from > that way of thinking. ... or perhaps it is not so much the way of thinking? I would expect that Python has a lot more person power than Sage. How many people do release management for Python? -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] Re: How can I make implicit_multiplication default?
Hi Robin, On 23 Aug., 13:43, robin hankin wrote: > Re automatic_names(): why isn't this the default? > > Now I know it exists, I think I'll probably use it all the time. > > Who uses sage without this option? I find automatic_names horrible, to say the least! In my opinion, such thing should *never ever* be standard! 1. If you write a little program on the command line and it does something, but simply it doesn't do the right thing or you get strange error messages about missing attributes -- it would be very hard to find out that you forgot to define some object X, so that Sage worked in the wrong assumption that X is a symbolic variable. I strongly prefer to get a clear error message, namely "NameError: Name 'X' is not defined" or so. 2. "Explicit is better than implicit" is a quite common credo. I think it is unsafe to rely on implicit assumptions of the type of an object. 3. I hardly ever work with symbolic variables. So, I really don't see the point why "X" should default to a symbolic variable. 4. My impression is that for quite many people a symbolic variable is the first thing that comes to mind when computing in a CAS - and it takes them a long while until they find that for their particular problem a different class (like a polynomial) works much better. Making a symbolic variable the default, I am afraid that one would support the wrong belief that symbolic variables are good for *everything*. So, it is not so much that programs would break. But debugging would be more difficult, and it would teach the people the wrong lesson, IMHO. And on the other hand, I can't see how life with Sage would be any easier if automatic_names was the standard. Cheers, Simon -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
Re: [sage-support] Re: How can I make implicit_multiplication default?
Hello thanks for this. I liked the preparser manpage that Simon pointed me to. Re automatic_names(): why isn't this the default? Now I know it exists, I think I'll probably use it all the time. Who uses sage without this option? Or, more precisely, can anyone give me an example of a way of working with sage that this option will break? I'm hoping to understand why you expert sage users chose the default as you did. best wishes Robin On Mon, Aug 23, 2010 at 12:07 PM, Simon King wrote: > Hi Robin, > > On 23 Aug., 12:58, robin hankin wrote: >> But, if I didn't know it existed, how could I possibly have found it? >> (give me a pointer to a FAQ!) > > I just tried to find it in the FAQ, but without success. > > Anyway. If you know that it is called implicit_multiplication then > you can do > sage: implicit_multiplication? > to see the documentation, or consult the manual, e.g., at > http://www.sagemath.org/doc/reference/sage/misc/preparser.html#sage.misc.preparser.implicit_multiplication > > Of course, the manuals can also be searched. > > Cheers, > Simon > > -- > To post to this group, send email to sage-support@googlegroups.com > To unsubscribe from this group, send email to > sage-support+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-support > URL: http://www.sagemath.org > -- Robin Hankin Uncertainty Analyst hankin.ro...@gmail.com -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] Re: How can I make implicit_multiplication default?
Hi Robin, On 23 Aug., 12:58, robin hankin wrote: > But, if I didn't know it existed, how could I possibly have found it? > (give me a pointer to a FAQ!) I just tried to find it in the FAQ, but without success. Anyway. If you know that it is called implicit_multiplication then you can do sage: implicit_multiplication? to see the documentation, or consult the manual, e.g., at http://www.sagemath.org/doc/reference/sage/misc/preparser.html#sage.misc.preparser.implicit_multiplication Of course, the manuals can also be searched. Cheers, Simon -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
Re: [sage-support] Re: How can I make implicit_multiplication default?
Hello everybody >> > implicit_multiplication is very time-saving, and a much more natural way >> > to write things. I'd love it to be default. Wow, implicit_multiplication(True) is *exactly* what I have been looking for. I have tried it just now, and it is brill. OK, my question: Now that I know implicit_multiplication() exists, I can search for it and get documentation about it. But, if I didn't know it existed, how could I possibly have found it? (give me a pointer to a FAQ!) best wishes rksh -- Robin Hankin Uncertainty Analyst hankin.ro...@gmail.com -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
[sage-support] Re: Those cookies again...
Hi All! Shouldn't this discussion better go to sage-devel? On 22 Aug., 22:01, "Dr. David Kirkby" wrote: > ... > http://www.python.org/dev/peps/pep-0006/ Quoting from this source: "In general, only the N-1 release will be under active maintenance at any time. That is, during Python 2.4's development, Python 2.3 gets bugfix releases." I see that simultaneously, there is work on Python 2.6.6 final (to appear tomorrow) and Python 3.2 alpha2 (to appear September 5th). My impression is that the Sage development process is quite far from that way of thinking. First of all, is there in Sage the concept of "maintenance" of a previous version? Usually, if people hit a problem with, say, sage-4.4, then they are told that they use a bronze age version and should upgrade to the *latest* version sage-4.5.2. According to the above quote, one would rather say "upgrade to bugfix release sage-4.4.3". So, in a way, only one Sage version is actively maintained at a time, namely always the latest version. If I remember correctly, there recently was a thread (sage-devel?) about the role of milestones in the Sage trac. My impression is that people virtually always choose the earliest possibility in the "milestone" menue. Having bugfix releases would require a change of attitude. People should tick 4.5.3 *only* if they have a bugfix. Otherwise, they should tick 4.6 or 5.0. But then it may even be worth to change the milestone menu. Perhaps: "bugfix only" (without mentioning a number, as this will always go into the earliest possible release), "minor addition: 4.5.3" (There is no change in existing code and little new code, so, it may be safe to consider early inclusion - but care has to be taken, as it is more than a bugfix) "minor addition: 4.5.4" (dito) "major addition: 4.6" (There is much testing required, as there is change in old code or there is much new code) "critical change: 5.x" (in contrast to an addition, a change might not be fully compatible with Sage-4.x and will thus not go in before version 5.0) At this point, a question on the current milestones: What is the meaning of the milestones "sage-invalid/duplicate/wontfix" and "sage- i18n"? The former looks more like a resolution (not a milestone) of a ticket, and the latter is totally obscure to me. Cheers, Simon -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
Re: [sage-support] Re: solve() problem
Hello everyone
thanks for the help here.
In Mathematica, Reduce[] works like Solve, except that it returns a
Boolean list of possible solutions. I use it to check what
the necessary conditions for the"real" solution to work:
MMA> Reduce[a*x == b, {x}]
MMA> (b == 0 && a == 0) || (a != 0 && x == b/a)
best wishes
rksh
On Fri, Aug 20, 2010 at 1:14 AM, kcrisman wrote:
>
>
> On Aug 19, 5:39 pm, robin hankin wrote:
>> Hello Simon
>>
>> thanks for this. One problem
>> with the solution you mention is that I can't do the
>> general case. What I need is the sage equivalent
>> of mathematica's Reduce[] function.
>>
>
> I think that solve() is the closest that comes to this (though
> admittedly I am no Mma expert).
>
> It turns out that even in Maxima straight up, this doesn't work
> (either with solve() or to_poly_solve()). I think maybe it doesn't
> know how to handle the conjugate() piece. There are however a lot of
> solvers in Maxima, so it's possible that one of them will do it
> (perhaps with a certain flag set. You're also right that doing the
> general case doesn't quite work - even if one puts that
> p^2+q^2==r^2+s^2, so to speak.
>
> I've wanted to put more work into exposing Maxima functionality like
> this but have not been able make the time, because if we're going to
> hook in deeper we need to do it right. But solving non-linear systems
> like this is probably one of the places we'd like to improve the most.
>
>
> - kcrisman
>
> --
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>
--
Robin Hankin
Uncertainty Analyst
hankin.ro...@gmail.com
--
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