[racket] Math library ready for testing

2012/12/8 Danny Yoo <dyoo at hashcollision.org>:
>> Or maybe using a : or something to separate rows for 2D arrays?
>> (array 1 2 : 3 4)

The matrix library uses arrays to represent the matrices.
An 2x3 matrix can be constructed as:

   (matrix/dim 2 3
                       1 2 3
                       4 5 6)

   (list->matrix '[[1 2 3] [4 5 6]])

  (for/matrix: : Number 2 3 ([i (in-naturals)]) i)

These expressions will all return the same 2D array.

Given that the shape of a matrix is fixed, the problems
with square parentheses in constructor notation disappear.
That is, one could let  matrix  be a macro, and it could
accept both kinds of parentheses:

      (matrix [[1 2 3] [4 5 6]])
      (matrix ((1 2 3) (4 5 6)))

See more matrix examples here:
https://github.com/plt/racket/blob/master/collects/math/tests/matrix-tests.rkt

-- 
Jens Axel Søgaard