function output = fftn(input)
% Wrapper function for fft3 for the GPUmat toolbox. This function should be
% renamed to fftn.m and placed in the /@GPUtype folder within the GPUmat
% toolbox directory. This allows k-Wave to work with the option 'DataCast'
% set to 'GPUsingle' or 'GPUdouble'. The .txt extension is used by default
% to prevent errors if users install the toolbox using the add subfolders
% option. 
%
% author: Bradley Treeby
% date: 24th May 2010
% last update: 24th May 2010
output = fft3(input);