I told my friend about how nice J was. Am I wrong?
He said, how fast can you multiply a 1000x1000 matrix times
a 1x1000 vector to get a 1x1000 resultant vector.
his MatLab code ran in about .6 seconds.
His code follows..
matrix = randn(312,256);
vector = randn(256,1);
tic
for i = 1:1000
output = matrix*vector;
end
toc
I wrote my code which runs in about 2.5 minutes
here is my code:
#!/home/efittery/bin/jconsole
A =: 256 312 $ 1+ i. 312 * 256x
B =: 312 1 $ 1+ i. 312x
jumbo =: monad define
for. i. y do.
yVector =: A +/ .* B
end.
)
jumbo 1000
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