append the scalar
y = moc_postpad (x, l,c) y = moc_postpad (x, l,c,dim)
append the scalar value c to the vector x until it is of length l. If the third argument is not supplied, a value of 0 is used.
If length (x > l), elements from the end of x are removed until a vector of length l is obtained.
If x is a matrix, elements are prepended or removed from each row.
If the optional dim argument is given, then operate along this dimension.