Create a new tab in the MATLAB editor window, and copy the entire text below into the window, and then save window as sample_advance.m
%%%% function to time-advance signal, preserve buffer length and pad with externally defined value
function op=sample_advance(ip, nshift, padding);
siglen=length(ip);
ip(1:siglen-nshift) = ip(nshift+1:siglen); %%%%% shift the bulk
ip(1+siglen-nshift:siglen) = padding; %%% obliterate bit at end with externally-defined fill
op = ip;
The function can also be found here:
https://figshare.com/articles/software/sample_advance_m/5297188