Need help for explanation of one command

This is part of code

x = zeros(size(y));  % Making a row vector x which is having length equal to y and all contents of x are 0.
*x(1:length(ADSR)) = ADSR;*    %----> What this line is doing, I know it is padding zeros but what is logic for that

Answer 1

[Fangjun Jiang]

This is the code Walter provided in your previous question. It's a different way to do zero-padding.

Conventional Way: (assume ADSR is a 1xn vector)

x=ADSR; x=[ADSR,zeros(1,100)];

Walter's suggestion is to set x to be all zero first and then copy the value of ADSR to the beginning of x, that is what x(1:length(ADSR)) = ADSR does.

The potential issue is to make sure the length of x is bigger than the length of ADSR. Otherwise, x will end up with the same as ADSR.

[moonman]

thanks Jiang

then copy the value of ADSR to the beginning of x, that is what x(1:length(ADSR)) = ADSR does.

This is what i was looking for

Answer 2

[Daniel Shub]

If ADSR is of length N and y is of length M, then at the end, x will have at least length N (and possibly length M) depending on if N is greater or less then M. Now as for why you might want to pad zeros on ADSR, you haven't provided nearly enough information.

Answer 3

[Jan]

You know, what happens, and you ask, what the logic for it is. The question is not clear. Obvious any part in the program needs, that X contains the vector ADSR and some zeros to have the same length as y.