[with patch, positive review] deprecate substitution via __call__ w/ unnamed arguments

[Carl Witty]

As discussed on sage-devel here: ​http://groups.google.com/group/sage-devel/browse_thread/thread/b1a03f8fc8ae8fcd/553773d7ba600ae7#553773d7ba600ae7

I added deprecation warnings to the four affected call functions (two for symbolic values, one for equations, one for matrices), and fixed almost all the warnings in all the doctests other than the doctests specifically for those call methods.

There's one set of warnings that I didn't figure out how to fix (in piecewise.py), so I just added the warning to the expected output for now.

[Michael Abshoff]

Two trivial doctest failures:

sage -t -long devel/sage/doc/en/constructions/calculus.rst # 1 doctests failed
sage -t -long devel/sage/doc/fr/tutorial/tour_algebra.rst # 1 doctests failed

Cheers,

Michael

[Carl Witty]

Oops, forgot to doctest the documentation. I've replaced my original patch with a new one that also fixes these two doctest failures.

[Jason Grout]

This is an (email) reminder to myself to review this to get it in.

[Jason Grout]

This ticket probably also affects #5093.

[Burcin Erocal]

Thanks for working on this Carl.

I only read the patch, didn't test it yet. Explicitly having to use .function() in two places bothers me:

• for each component of Piecewise
• in the call to generate_plot_points

Perhaps we should modify these to handle non function arguments more gracefully after this change.

I understand that this might require a new syntax to construct Piecewise objects. One option is to add a new parameter, which includes an ordered list of variables. E.g.,

    sage: Piecewise([[(0,1),x^2],[(1,2),5-x^2]] ,[x])

or

    sage: f = Piecewise([[(-1,1),1/2+x-x^3 + y]],[x,y])

Comments?

[Jason Grout]

The above comment for Piecewise would probably also apply to symbolic matrices and vectors, right? (well, at least, as soon as symbolic vectors are callable, anyway). I think that Burcin's proposal is okay, but doesn't extend very well to matrices and vectors, since I'd hate to mess up the standard matrix/vector constructors. I'm don't know a better way to extend this to matrices and vectors, though. Maybe we ought to just deprecate calling a symbolic matrix without keyword arguments, and just implement the callable symbolic vector with the same restrictions.

[Carl Witty]

The patch already does deprecate calling a symbolic matrix without keyword arguments.

[Jason Grout]

Yes. I thought Burcin's comment was about a syntax to avoid the .function() call. That's what I was commenting on.

[Carl Witty]

After discussions on IRC and sage-devel (​http://groups.google.com/group/sage-devel/browse_thread/thread/97cdf80edb089481/73e8e6659c09e1d9#73e8e6659c09e1d9) we've decided on a much more extensive deprecation scheme. So it's not worth reviewing the current patch. (I should have a new patch within a few days.)

[Carl Witty]

I've posted a patch that implements the more extensive deprecation described here: ​http://groups.google.com/group/sage-devel/browse_thread/thread/97cdf80edb089481#

The patch now depends on #5093.

Apply only the second patch.

[Jason Grout]

This is really odd:

[19:53] <jason> sage: g(x)=sin
[19:53] <jason> sage: g(3)
[19:53] <jason> sin(3)
[19:53] <jason> sage: g(x)=sin+x
[19:53] <jason> sage: g(3)
[19:53] <jason> sin + 3
[19:54] <jason> but
[19:54] <jason> sage: g(x)=sin+cos; g(3)
[19:54] <jason> sin + cos

[Burcin Erocal]

Jason, I get the same behavior without Carl's patch on Sage-3.4. I suggest moving that to a separate ticket. We could also argue if that is valid syntax there.

I give a positive review to this. It would be good to get this in an alpha and let more people play with it. Thanks again Carl.

Cheers, Burcin

[Burcin Erocal]

comment:12 is now #5607.

[Jason Grout]

I agree that we should get this into the alpha so it gets wider exposure. (providing doctests pass) positive review from me too.

[Michael Abshoff]

There is one tiny doctest issue left - at least in my merge tree :)

sage -t -long "devel/sage/doc/en/constructions/calculus.rst"
**********************************************************************
File "/scratch/mabshoff/sage-3.4.1.alpha0/devel/sage/doc/en/constructions/calculus.rst", line 222:
    sage: f.integral()
Expected:
    Piecewise defined function with 2 parts, [[(0, 1), x^3/3], [(1, 2), (15*x - x^3)/3 - 13/3]]
Got:
    Piecewise defined function with 2 parts, [[(0, 1), x |--> x^3/3], [(1, 2), x |--> (15*x - x^3)/3 - 13/3]]
**********************************************************************
1 items had failures:
   1 of   9 in __main__.example_8
***Test Failed*** 1 failures.
For whitespace errors, see the file /scratch/mabshoff/sage-3.4.1.alpha0/tmp/.doctest_calculus.py
	 [4.3 s]
exit code: 1024

I am fixing this with a reviewer patch.

Cheers,

Michael

[Michael Abshoff]

Merged trac5413-deprecate-symbolic-unnamed-call.patch and trac_5413-reviewer.patch in Sage 3.4.1.alpha0.

Cheers,

Michael