On Sat, Aug 14, 2010 at 12:05 PM, Jason Grout <jason-s...@creativetrax.com> wrote: > On 8/14/10 10:46 AM, Maurizio wrote: >> >> >> On 12 Ago, 09:49, Jason Grout<jason-s...@creativetrax.com> wrote: >>> >>> On 7/22/10 2:36 PM, Maurizio wrote: >>> >>> >>> >>> >>> >>>> I have a quick question that is related to engineering support (I was >>>> reading the document you posted on the wiki about sd24, and I see the >>>> roadmap is planning to address those issues for SAGE 7.0.. ouch!): I >>>> don't know exactly how this is achieved, but I can see that >>> >>>> sage: type(1) >>>> <type 'sage.rings.integer.Integer'> >>> >>>> this should come from the fact that the preparser replaces usual >>>> numbers with sage numerical types. >>>> Nonetheless, still we have: >>> >>>> sage: type([1,2,3]) >>>> <type 'list'> >>> >>>> This means that list are not replaced by anything internal, even if >>>> they are collector of python objects which are still sage numbers. I >>>> wonder which is the policy of SAGE towards arrays and matrices. I >>>> think there is a good base in numpy and scipy, so I wonder if it would >>>> make sense to let the preparser transform any list of numbers into a >>>> numpy array. That would greatly improve user ergonomy in case of raw >>>> numbers manipulation. >>>> That could be a not-default option, that could be activated using a >>>> function like: >>> >>>> def numpy_mode(str): >>>> if str == 'on': >>>> from numpy import * >>>> "turn any list into a numpy array" >>>> elif str == 'off': >>>> "reverse behaviour" >>> >>>> [I'm just talking on top of my head] >>> >>> This will probably require lots of changes in the sage codebase, since I >>> think there are lots of places that an input is tested to see if it is a >>> list. >>> >>> % find . -name \*.py\* | xargs grep isinstance |grep list|wc -l >>> 545 >>> >>> >>> >>>> Another slightly related issue is: could we make >>>> plot(numpy.array([1,2,3,4])) behave like >>>> list_plot(numpy_array([1,2,3,4]))? The way it is now, it just doesn't >>>> work... >>> >>> +1 to plot interpreting numpy arrays. However, shouldn't it interpret >>> the numpy arrays like it interprets lists? Right now, plot([1,2,3]) >>> works and plots the constant functions 1, 2, and 3. >>> >>> Thanks, >>> >>> Jason >> >> What would you expect from such a plot([1,2,3])? Personally,a plot of >> a list of points. If the argument of plot is a list of constant >> values,can we imagine to change the behavior such to replicate that of >> list_plot? >> > > > What do you expect from plot(1)? The constant function 1 sounds reasonable.
Absolutely, definitely, without any question, one should get the plot of the constant function 1. > Sage also lets you specify multiple functions using a list, so it follows > that plot([1,2,3]) is a plot of the constant functions. I'm not agreeing or > disagreeing, but just pointing out the reasoning. I very strongly agree that "plot([1,2,3])" should plot 3 constant functions, f(x)=1, g(x)=2, and h(x)=3. This is a special case of something we've clearly defined more generally, so it must be supported like this. > On the other hand, I would definitely expect that points([1,2,3]) should > give what you are saying (points (1,1), (2,2), (3,3)). I don't agree. Points([1,2,3]) should either give an error or work as it does now (draws a point in 3d). I would be fine with it giving an error... I think points=point right now, which is why you get a point in 3d, or point([1,2]) gives a point in 2d. William > > Thanks, > > Jason > > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org > -- William Stein Professor of Mathematics University of Washington http://wstein.org -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
