[Maxima-discuss] additional display flags for matrix, determinant, and box expressions

[Robert D. <rob...@gm...>]

I've taken the liberty of extending the display flags for matrix,
determinant, and box expressions. See commits 99a826..66001d on master.

For matrix(...), display_matrix_brackets (default true) governs whether
brackets are placed on either side of a matrix. Otherwise the matrix
elements are displayed without brackets. This flag has the expected effect
when display2d_unicode = true and display2d_unicode = false.

For determinant(...), display_determinant_bars (default true) governs
whether vertical bars are placed on either side of the matrix in an
expression 'determinant(matrix(...)) . Otherwise the expression is
displayed as an ordinary function call, as it is now. This flag has the
expected effect when display2d_unicode = true and display2d_unicode = false.

For box(...), display_box_double_lines (default true) governs whether
box(...) expressions are drawn with double-line Unicode characters, as they
are now, or single-line Unicode characters.This flag has an effect only
when display2d_unicode = true. I guess I could have imagined something
sensible to do when display2d_unicode = false for the sake of consistency
... I might still do that.

I only worked on the 2-d pretty printer -- I didn't try to update any other
displays such as tex(...) output.

Here is a tiny demo. See rtest_unicode_display.mac and
test_matrix_display.mac in the tests folder for additional examples.

(%i2) foo: matrix ([a, b, c], [d, e, f], [g, h, i]);
                           ┌         ┐
                           │ a  b  c │
                           │         │
(%o2)                      │ d  e  f │
                           │         │
                           │ g  h  i │
                           └         ┘
(%i3) 'determinant (foo);
                           │ a  b  c │
                           │         │
(%o3)                      │ d  e  f │
                           │         │
                           │ g  h  i │
(%i4) box (%o2);
                          ╔═══════════╗
                          ║┌         ┐║
                          ║│ a  b  c │║
                          ║│         │║
(%o4)                     ║│ d  e  f │║
                          ║│         │║
                          ║│ g  h  i │║
                          ║└         ┘║
                          ╚═══════════╝
(%i5) display_matrix_brackets: false $
(%i6) foo;
                             a  b  c

(%o6)                        d  e  f

                             g  h  i
(%i7) display_box_double_lines: false $
(%i8) %o4;
                           ┌─────────┐
                           │ a  b  c │
                           │         │
(%o8)                      │ d  e  f │
                           │         │
                           │ g  h  i │
                           └─────────┘


This 2-d Unicode stuff looks pretty bad in the Gmail composer, as
the vertical characters don't join up. It looks much better in a terminal,
where the vertical characters abut one another. I hope that what you see is
more like the latter than the former.

Hope this helps in some way.

Robert