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function [y]= dctmtx(n)
// Performs Direct Cosine Transformation
// Calling Sequence
// [y]=dctmtx(n)
// Parameters
// n: Real scalar integer greater than or equal to 1
// Description
// This is an Octave function
// dctmtx(n) returns a Discrete cosine transform matrix of order n-by-n. It is useful for jpeg image compression. D*A is the DCT of the columns of A and D'*A is the inverse DCT of the columns of A (when A is n-by-n).
// Examples
// 1. dctmtx(2)
// ans = [0.70711 0.70711; 0.70711 -0.70711]
// 2. dctmtx(3)
// ans = [5.7735e-01 5.7735e-01 5.7735e-01;
// 7.0711e-01 4.9996e-17 -7.0711e-01;
// 4.0825e-01 -8.1650e-01 4.0825e-01]
funcprot(0);
rhs=argn(2);
if (rhs<1) then
error ("Wrong number of input arguments.")
else [y]=callOctave("dctmtx",n)
end
endfunction
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