Cellfun on cellarray from textread not working

Hey there, I have a textfile with 13 rows and one single string in every row, reading it to a cellarray with:

fileID = fopen('C:\file.txt');
C = textscan(fileID,'%s');

What I'm trying now is to get the first 4 letters all lowercase from the strings in the cells. Using

lowerC = cellfun(@lower, C, 'UniformOutput', false)

works fine. But when I try to get the first four letters (descriped here, 3rd example: http://www.mathworks.de/de/help/matlab/ref/cellfun.html) with

abbrev = cellfun(@(x) x(1:4), Clowercase, 'UniformOutput', false)

I get the output

abbrev = 
    {4x1 cell}

with only the first four (lowercase but full length) strings ...

When defining

C = {'AAAA1', 'BBBB2', 'CCCC3', 'DDDD4', 'EEEE5'};

It will work. Can someone explain me the difference between the manually defined cellarray and the one textscan is defining?

Thank you very much in advance!

Answer 1

[Guillaume]

This is probably because textscan returns a cell array (one cell, as you only specify one field) of cell arrays. The following should work:

fileID = fopen('C:\file.txt');
C = textscan(fileID,'%s');
lowerC = cellfun(@lower, C{1}, 'UniformOutput', false); %Note the {1}
abbrev = cellfun(@(x) x(1:4), lowerC, 'UniformOutput', false);
%or to be safe, if any element is shorter than 4 chars
abbrev = cellfun(@(x) x(1:min(end, 4)), lowerC, 'UniformOutput', false);

textscan returns a cell array where each column correspond to a field in the format string. You've only specified one field, so you get one cell. Because that field is %s that single cell is a cell array of string.

[Stefan]

Thank you very much :) I already suspected the celly array was kinda different and I think I have to reread the chapter about it :D