Why is MATLAB unable to read an ASCII file containing a large amount of data in a single line using the CSVREAD function?

Why is MATLAB unable to read an ASCII file containing a large amount of data in a single line using the CSVREAD function?

Answer 1

[MathWorks Support Team]

This bug has been fixed in Release 14 Service Pack 2 (R14SP2). For previous releases, please read below for any possible workarounds:

This has been verified as a bug in MATLAB in the way that the CSVREAD function handles large data files.

Currently, as a workaround, try the following code:

fid = fopen('filename'); 

a = textscan(fid,'%n','delimiter',',');

This reads the file rather quickly and creates an array of doubles. The difference is that when CVSREAD reads the same file, it tries to have a format string with thousands of fields, one for each line of data.