Why does import data hang up on 70 Mb file?

I'm trying to import data files consisting of lots of numbers from a text file. The data are not in columns they are just space delimited values in a text file.

Using importdata works on files < 10Mb but more than that, MatLab hangs up on me. Is there a better way to import numbers from a large text file. I've looked at filescan, but i don't see the advantage.

any advice would be appreciated.

Answer 1

[dpb]

Are the values consistently space-delimited, not fixed width fields I gather from the description? If there aren't missing values, then the simplest would be textread which is the "red-haired stepchild" but has the advantage of not requiring cell arrays when don't need 'em and also handles the filename directly w/o the need for fopen explicitly.

Just try

x=textread('yourfilename');

and see if that doesn't please...alternatively, also almost trivial is

x=dlmread('yourfilename');

where the delimiter is inferred from the file. This is good as it then treats multiple delim's as one whereas if specify 'delimiter',' ' the extras will be significant.

textscan can do the same but to get the shape correct you have to know the number of fields/row which the above do automagically.