MATLAB: How to import some large data please

big datadataextraction

Hi all I have a file called DJ.csv which has 5 columns. 1) Dates (01/02/2007), 2) Times (30.42.0), 3) prices 12553, 12442, 4) Codes (DJ123) and 5) trade size.
I want to take column 3 and 5 (price and trade size into matlab). I am having some trouble as the csv is quite big.
I tried this:
fileID = fopen('K:\test\test\DJ.csv');
A = fread(fileID,'double');
fclose(fileID);
But it only gives me a vector of values which are not the same as my data. Any help would be very much appreciated.
Thanks.

Best Answer

fread is for stream unformatted files; you have formatted delimited file--
doc textscan % and friends
If you really only want/need the two columns sotoo (air-code, untested)
[p,s]=textread('K:\test\test\DJ.csv','%*s%*s,%f%*f%f','delimiter',',');
ought to do unless the third column is indeed a comma-for-a-decimal point as well as a comma-delimited file. In that case you've got a problem. You'll have to read three values instead of just two or preprocess the file or otherwise handle the decimal separator as Matlab can't (and you can't expect it to) know the difference between comma-delimiters and decimal places.
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