Plot an eye diagram of a signal in MatLab

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The matrix X contained in a .mat file represents the acquired signal. The element of place (i, j) of the matrix is the i-th sample of the j-th screen. The sampling frequency is equal to 4 GS/s. How do I plot the eye diagram relative to the signal contained in X using MatLab? I tried but I could not draw the eye diagram from the matrix X (see http://ge.tt/8Xq5SYh/v/1?c). Here is the link to the matrix X that I used:

http://ge.tt/8Xq5SYh/v/0

Someone could try to show me how to do? Maybe the matrix is not correct?

Thanks in advance to anyone who answers