iadctmatrix
Kernel matrix for the DCT Transform.

>>> A = iadctmatrix(128)

>>> iashow(A)

(128, 128) Min= -0.12499058773 Max= 0.12499058773 Mean=0.001 Std=0.09

>>> import Numeric

>>> A = iadctmatrix(4)

>>> print Numeric.array2string(A, precision=4, suppress_small=1)

[[ 0.5     0.5     0.5     0.5   ]
 [ 0.6533  0.2706 -0.2706 -0.6533]
 [ 0.5    -0.5    -0.5     0.5   ]
 [ 0.2706 -0.6533  0.6533 -0.2706]]

>>> B = Numeric.matrixmultiply(A,Numeric.transpose(A)) 

>>> print Numeric.array2string(B, precision=4, suppress_small=1)

[[ 1.  0. -0. -0.]
 [ 0.  1.  0.  0.]
 [-0.  0.  1.  0.]
 [-0.  0.  0.  1.]]