idst1 This function computes the inverse type I discrete sine transform. Y = idst(X) Y = idst(X, N) X: Matrix or integer N: If N is given, then X is padded or trimmed to length N before computing the transform. This function computes the inverse type I discrete sine transform of Y. If N is given, then Y is padded or trimmed to length N before computing the transform. If Y is a matrix, compute the transform along the columns of the the matrix.