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6:40:11
unixlisp
aeth: oh, this is the correct expression in maxima (($matrix) ((mlist) 1 2 3) ((mlist) 4 5 6) ((mlist) 7 8 9)) about [1 2 3; 4 5 6; 7 8 9] in octave.
6:53:43
unixlisp
in maxima, some matrix operation such as triangularize also use make-array to optimise.
7:52:20
unixlisp
ppcre::nsubseq is a frequently used function made a displaced array. in sbcl, it makes a displaced array adjustable, in ccl not adjustable.
11:48:31
unixlisp
zetaE_: load("ezunits"); declare_unit_conversion (arc_degree = %pi/180);(lisp-form "cos(45 ` arc_degree)"); => 1/sqrt(2)
14:48:11
aeth
I suppose the Lispy way to do MATLAB-style matrices would be to have another way to write ; (I mean, you could obviously just write #\; too, but that gets rid of the inconvenience)
14:48:55
aeth
[1 2 3; 4 5 6; 7 8 9] vs (1 2 3 :n 4 5 6 :n 7 8 9) or whatever you want the "newline" to be
15:16:41
mdhughes
Then you can reference the vectors normally; I hate row-major indexing, but it's the natural result here.
15:31:18
mdhughes
What? Tons of old graphics libraries in particular use row-major and it drives me up the wall. Column-major (in >2D, just reverse order) allows you to refer to coordinates in a structure naturally [x][y][z] etc.
15:41:40
moon-child
better is to abstract and perform the indexing over some kind of coordinate object