character art: line wrapping for matrices

[mwageringel]

This ticket adds breakpoints to the ASCII and unicode art representations of matrices, so that wide matrices are wrapped in a readable way:

sage: %display unicode_art 80
sage: set_random_seed(0)
sage: matrix.random(RDF, 3, 8)
⎛ -0.27440062056807446    0.5031965950979831 -0.001975438590219314
⎜ -0.35104242112828943    0.5084492941557279   0.19906256610645512
⎝ -0.20282268041839324    0.0728476884470246   -0.9938082549986424

   -0.9467802263760512    0.5056889961514748  -0.05461130074681608
    0.3242250183948632    0.6026443545751128   -0.9541798283979341
  0.004239223023573491   -0.6670085876677831    -0.635743483594841

 -0.033673314214051286   -0.9401270875197381⎞
   -0.8948790563276592   -0.5763034867990717⎟
    0.5778937006648461   -0.9007365327499568⎠

Previously, the output was completely scrambled if the matrix was wider than the window size:

⎛ -0.27440062056807446    0.5031965950979831 -0.001975438590219314   -0.94678022
63760512    0.5056889961514748  -0.05461130074681608 -0.033673314214051286   -0.
9401270875197381⎞
⎜ -0.35104242112828943    0.5084492941557279   0.19906256610645512    0.32422501
83948632    0.6026443545751128   -0.9541798283979341   -0.8948790563276592   -0.
5763034867990717⎟
⎝ -0.20282268041839324    0.0728476884470246   -0.9938082549986424  0.0042392230
23573491   -0.6670085876677831    -0.635743483594841    0.5778937006648461   -0.
9007365327499568⎠

Component: misc

Keywords: ascii_art, unicode_art

Author: Markus Wageringel

Branch/Commit: 448cdcd

Reviewer: Vincent Delecroix

Issue created by migration from https://trac.sagemath.org/ticket/29203

[mwageringel]

comment:1

There is one small caveat: In the case of lists of matrices that do not exceed the window width, it can happen that now the output is wrapped

sage: %display unicode_art 80
sage: set_random_seed(0)
sage: [matrix.random(RDF, 3, 2), matrix.random(RDF, 3, 3)]
⎡ ⎛ -0.27440062056807446    0.5031965950979831⎞  ⎛-0.033673314214051286
⎢ ⎜-0.001975438590219314   -0.9467802263760512⎟  ⎜   0.5084492941557279
⎣ ⎝   0.5056889961514748  -0.05461130074681608⎠, ⎝   0.6026443545751128

   -0.9401270875197381  -0.35104242112828943⎞ ⎤
   0.19906256610645512    0.3242250183948632⎟ ⎥
   -0.9541798283979341   -0.8948790563276592⎠ ⎦

while previously the matrices were displayed in one piece:

⎡ ⎛ -0.27440062056807446    0.5031965950979831⎞
⎢ ⎜-0.001975438590219314   -0.9467802263760512⎟
⎣ ⎝   0.5056889961514748  -0.05461130074681608⎠,

 ⎛-0.033673314214051286   -0.9401270875197381  -0.35104242112828943⎞ ⎤
 ⎜   0.5084492941557279   0.19906256610645512    0.3242250183948632⎟ ⎥
 ⎝   0.6026443545751128   -0.9541798283979341   -0.8948790563276592⎠ ⎦

This is fixed by #29204, but – even without that ticket as a dependency – it would make sense to merge this ticket because the output of wide matrices is so vastly improved in all other cases.

[mwageringel]

Branch: u/gh-mwageringel/29203

[mwageringel]

Author: Markus Wageringel

[mwageringel]

Commit: 448cdcd

[mwageringel]

Changed keywords from none to ascii_art, unicode_art

[mwageringel]

New commits:

448cdcd

29203: add breakpoints to character art of matrices

[videlec]

comment:3

What is the rationale for the globally defined max_rows = 20 and max_cols = 50 (that are used in _ascii_art_)?

[mwageringel]

comment:4

In plain text mode, matrices larger than that do not show their entries by default, but print a summary instead:

sage: %display plain
sage: matrix.identity(20)
20 x 20 dense matrix over Integer Ring (use the '.str()' method to see the entries)

This behavior is copied by ascii_art and unicode_art.

sage: %display ascii_art
sage: matrix.identity(20)
20 x 20 dense matrix over Integer Ring

Being global variables, one can set different default values for these variables in init.sage to customize this behavior.

Note that the message (use the '.str()' method to see the entries) is not part of the repr, but is added by the display manager using LargeMatrixHelpRepr, which is not used in ascii_art display mode.

[videlec]

Reviewer: Vincent Delecroix

[videlec]

comment:5

I see. However, I doubt that among developers 20% know about the max_rows/max_cols customization... Note that integer partitions introduced Partitions.options.display to deal with printing details.

Anyway, this is not the purpose of the ticket! I am running the doctests on my machine (since the patchbots seem to be on strike).

[mwageringel]

comment:7

Thank you for the reviews.

[vbraun]

Changed branch from u/gh-mwageringel/29203 to 448cdcd