Matrix Printing

[dragonfly-ai]

The next version of SLASH will feature matrix rendering analogous to the features already supported for vectors. Besides the obvious CSV and TSV, what other ways should we print matrices?

We can support as many of them as we can name, but for the default, do any of these options appeal to you:

A:
Mat₍₃ₓ₃₎⌈0.26551922805679196, 0.43687247199421475, 0.43832596619253417⌉
        |0.33117546170002754,  0.7109260888478628,  0.6122290273291641|
        ⌊ 0.7445021387564973,  0.8501982325949996, 0.11210447085077846⌋

B:
Mat₍₃ₓ₃₎ ⌈ 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 ⌉
         | 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
         ⌊  0.7445021387564973,  0.8501982325949996, 0.11210447085077846 ⌋

C:
Mat₍₃ₓ₃₎
⌈0.26551922805679196, 0.43687247199421475, 0.43832596619253417⌉
|0.33117546170002754,  0.7109260888478628,  0.6122290273291641|
⌊ 0.7445021387564973,  0.8501982325949996, 0.11210447085077846⌋

D:
Mat₍₃ₓ₃₎
⌈ 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 ⌉
| 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
⌊  0.7445021387564973,  0.8501982325949996, 0.11210447085077846 ⌋

E:
Mat⌈0.26551922805679196, 0.43687247199421475, 0.43832596619253417⌉
   |0.33117546170002754,  0.7109260888478628,  0.6122290273291641|
   ⌊ 0.7445021387564973,  0.8501982325949996, 0.11210447085077846⌋₍₃ₓ₃₎

F:
Mat⌈ 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 ⌉
   | 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
   ⌊  0.7445021387564973,  0.8501982325949996, 0.11210447085077846 ⌋₍₃ₓ₃₎

G:
Mat⌈ 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 ⌉
₃ₓ₃| 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
   ⌊  0.7445021387564973,  0.8501982325949996, 0.11210447085077846 ⌋


F:
Mat₍₃ₓ₃₎⌈                                                               ⌉
        | 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 |
        | 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
        |  0.7445021387564973,  0.8501982325949996, 0.11210447085077846 |  
        ⌊                                                               ⌋


G:
                              Mat₍₃ₓ₅₎
⌈                                                               ⌉
| 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 |
| 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
|  0.7445021387564973,  0.8501982325949996, 0.11210447085077846 |  
⌊                                                               ⌋

H:
Mat₍₃ₓ₅₎
⌈                                                               ⌉
| 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 |
| 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
| 0.7445021387564973,   0.8501982325949996, 0.11210447085077846 |  
⌊                                                               ⌋

I:
⌈                                                               ⌉
| 0.26551922805679196, 0.43687247199421475, 0.43832596619253417 |
| 0.33117546170002754,  0.7109260888478628,  0.6122290273291641 |
| 0.7445021387564973,   0.8501982325949996, 0.11210447085077846 |  
⌊                                                               ⌋

Or would you like to see something completely different?

How about the matrix header:

1.  Mat[3x5]
2.  Mat[3ₓ5]
3.  Mat[₃ₓ₅]
4.  Mat₍₃ₓ₅₎
5.  Mat⸤₃ₓ₅⸥

Care to weigh in: @Quafadas @JD557 @nightscape @philwalk ?

[Quafadas]

In my pet project on Matricies, I essentially dodged this question on the back of this;

Maximum flexibility is the key requirement.

Which I totally agree with. What I want to see is very often context specific, in the most recent case 3dp, aligned on the '.', a col separator and a footer .

given Show[Matrix[Double]] with
  def show(matrix: Matrix[Double]): String =
    val rows =
      for i <- 0 until matrix.rows
      yield matrix
        .row(i)
        .map(s => "%.3f".format(s).reverse.padTo(6, ' ').reverse)
        .mkString(" | ")
    val footer = ("-" * (rows.head.length))
    (rows :+ footer).mkString("\n")

I think my only real suggestion would be to try and make that the "built in" made use of mechanisms which are exposed to the consumer, in case they did want to craft their own.

[JD557]

We can support as many of them as we can name, but for the default, do any of these options appeal to you:

Not entirely sure what should be the default, but it would be nice to have a pure ASCII option, for terminals/backends with UTF-8 issues.

For example: scala-native/scala-native#4144

[dragonfly-ai]

Added several matrix rendering options with configurable number formatting and column alignment.

Currently supporting unaligned, left aligned, right aligned, center aligned, and aligned on decimal.

Align on magnitude is tricky, but maybe soon.

[dragonfly-ai]

It's pushed: https://github.com/dragonfly-ai/slash/blob/main/slash/shared/src/main/scala/slash/matrix/Mat.scala#L1259