Question

How can I convert this script into a MATLAB function?

clear all;

set={AB02XY_1,ZT99ER_1,UI87GP_1};

fileData1 = load([fileString set{1} '.mat']);  
fileData2 = load([fileString set{2} '.mat']);  
fileData3 = load([fileString set{3} '.mat']);  

[A,B] = myfunction1_1(fileData1,fileData2,fileData3);

fileName = 'C:\Users\Documents\MATLAB\matrice_AAA001.mat';  
save(fileName,'A','B');

clear all;  

set={AB02XY_2,ZT99ER_2,UI87GP_2};

fileData1 = load([fileString set{1} '.mat']);  
fileData2 = load([fileString set{2} '.mat']);  
fileData3 = load([fileString set{3} '.mat']);  

fileData4 = load('C:\Users\Documents\MATLAB\matrice_AAA001.mat');

[A,B] = myfunction1_2(fileData1,fileData2,fileData3,fileData4);

fileName = 'C:\Users\Documents\MATLAB\matrice_AAA001.mat';  
save(fileName,'A','B');

I do processing on large data files, then to avoid the error ‘out of memory ‘, I split each file into two parts and I use at the beginning of each stage ‘clear all’. So, what I want is to have a function as AAA001 = function (AB02XY, ZT99ER, UI87GP, MyFunction1).
my problem is that I have to write the same script for other data files. So, is there a way to build a function where I can just change the file names AB02XY, ZT99ER, UI87GP, and the name of the function used ‘MyFunction1’ for the sub-processing to get on the last step the file AAA001.

NB: I simplified my script, but actually I divide each file into 5 parts. So I want to transform the 5 parts of my script in a single function!!!

Thank you for your help.

Answer 1

Here’s one way to do this. Call the function

 output = function ({'AB02XY', 'ZT99ER', 'UI87GP'}, 5, MyFunction1);

Note that I assume that you want 5 file parts

function out = myMainFunction(fileList, nParts, fun2run)
%# myMainFunction calculates output from multiple split files
%
%# SYNOPSIS out = myMainFunction(fileList, nParts, fun2run)
%#
%# INPUT    fileList: cell array with file body names, e.g.
%#                    'AB02XY' for files like 'AB02XY_1.mat'
%#          nParts  : number of parts in which the files are split
%#          fun2run : function handle or name. Function has to 
%#                    accept lenght(fileList) arguments plus one
%#                    that is the output of the previous iteration
%#                    which is passed as a structure with fields A and B
%#
%# OUTPUT   out : whatever the function returns
%#
%# Brought to you by your friends from SO


%# input checking should go here

if ischar(fun2run)
   fun2run = str2func(fun2run);
end

nFiles = length(fileList);


for iPart = 1:nParts

data = cell(nFiles,1);
for iFile=1:nFiles

data{iFile} = load(sprintf(%s_%i.mat',fileList{iFile},iPart));

end

if iPart == 1
   %# call fun2run with nFiles inputs
   [out.A,out.B] = fun2run(data{:});
else
   %# fun2run wants the previous output as well
   [out.A,out.B] = fun2run(data{:},out);
end

end %# loop parts