It took a while to puzzle thru what you're doing...I still have absolutely no klew as to why one would do this, but...
The problem in dimension arises by the way you're generating the vector y as
then subsequently you then try to refer to y w/ the subscript vector p again.
The assignment of
turns size(y) into [length(p),1] or, in the example given length(y) is now 14. But, the p index vector is a permutation of a subset of 14 values between 1-128 by
p = randperm(ofdm.N); p = p(1:k);
So, excepting for the one case which will likely never occur, you're trying to reference some non-existent value >14 in y with the subsequent assignment via the index vector p
Don't know what you want for a final output, but that's the problem with your indexing expression as written. OTHO,
will work if you want an input vector of the 14 values only w/o the zero-fill in the original.
