upsamp.m

这是伯克里wavelet transforms一书中的例子的代码

function uop = upsamp(ip,l)
%Upsampling routine 
%
%up = upsamp(data,L) takes a data matrix and upsamples 
%it's rows by a factor L, and returns the result in the 
%matrix up.
%
%The variables used are:
%data: Input data matrix
%l    : Upsampling factor
% 
%idea courtesy: Dinesh Nadarajah
%
%Author: Ajit S. Bopardikar
%Copyright (c) 1998 by Addison Wesley Longman, Inc.
%

 [r c] = size(ip); %determine the size of the input matrix
 uop = zeros([r,2*c]); %create a zero matrix with twice the number of columns
 uop(:,1:2:2*c) = ip;  %replace every other element of this matrix with
                       %the elements of the original matrix in a column
                       %wise fashion.