1. Plot the rows of the DCT matrix for n=4.

n = 4 ; dct = Table[ Cos[Pi/nj (k + 1/2)], {j, 0, n - 1}, {k, 0, n - 1}]//N ; dct//MatrixForm

( 1.` 1.` 1.` 1.` ... 0.38268343236508984` -0.9238795325112868` 0.9238795325112865` -0.3826834323650899`

Do[ ListPlot[dct[[j, All]], PlotJoinedTrue],  {j, 1, 4} ]

[Graphics:../HTMLFiles/index_4.gif]

[Graphics:../HTMLFiles/index_5.gif]

[Graphics:../HTMLFiles/index_6.gif]

[Graphics:../HTMLFiles/index_7.gif]

Created by Mathematica  (April 1, 2004)