Resolved: Need help for using textscan to read a csv file
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Below is my code. I could not find any issues with that. But the results "tmp" are always empty {0x70 cell}.
Please help. Thanks.
====== Code =======
fid = fopen('testfile.csv', 'rt');
formatspec = [repmat('%s ', 1, 70) '%*[^\n]'];
tmp = textscan(fid, formatspec, 1, 'delimiter', ',', 'collectoutput', true, 'headerlines', 16);
fclose(fid);
======= One row of the data file ========== 09FA20010524,09FA20010524,1,2.00105E+17,1,24,2,20010525,0,-44.429,179.9582,1011,989,1000.8,4.531,-999,9,34.307,2,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,2.781,2,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,9,-999,-999,-999,-999,-999,4.45259,27.1871,31.7778,36.2656,40.6526,44.9407
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Accepted Answer
dpb
on 9 Aug 2013
>> s='09FA20010524,09FA20010524,...,31.7778,36.2656,40.6526,44.9407';
>> fmt = [repmat('%s ', 1, 70) '%*[^\n]'];
>> textscan(s, fmt, 1, 'delimiter', ',', 'collectoutput', true)
ans =
{1x70 cell}
>> ans{1}
ans =
Columns 1 through 7
'09FA20010524' '09FA20010524' '1' '2.00105E+17' '1' '24' '2'
Columns 8 through 14
'20010525' '0' '-44.429' '179.9582' '1011' '989' '1000.8'
...
Columns 68 through 70
'44.9407' [] []
>> length(findstr(s,','))
ans =
67
Your problem is the last -- there are only 68 fields, not 70 at least in the above record and that combined w/ the last '%*[^\n]' in the format string causes the failure on subsequent lines. Also, lose the extra blank in the format string; it instructs textscan() to try to match an explicit blank of which there are none in the file--I'm a little surprised that didn't cause a failure.
Just use
fmt = repmat('%s', 1, 68);
should be all you need.
Check the input file for consistency in number of columns/record, though, too.
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