reading a csv file with a multiline header and alphanemeric dataset

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John
John am 16 Apr. 2014
Kommentiert: John am 22 Apr. 2014
I have a csv file (e.g. filename.csv) with a multiline, irregular header with a fixed length (17 lines). following this, there are columns of data, that I wish to make numeric array. columns may contain empty cells, and non numeric content, which I would want to replace with zeros in my resulting vector. here is the csv file, with a portion of the header:
"Legend"
"M","Missing"
"E","Estimated"
"NA","Not Available"
"**","Partner data that is not subject to review by the National Climate Archives"
"Date/Time","Year","Month","Day","Time","Data Quality","Temp (°C)","Temp Flag","Dew Point Temp (°C)","Dew Point Temp Flag","Rel Hum (%)","Rel Hum Flag","Wind Dir (10s deg)","Wind Dir Flag","Wind Spd (km/h)","Wind Spd Flag","Visibility (km)","Visibility Flag","Stn Press (kPa)","Stn Press Flag","Hmdx","Hmdx Flag","Wind Chill","Wind Chill Flag","Weather"
"2014-04-01 00:00","2014","04","01","00:00","**","2.4","","1.8","","74","","8","","17","","12.9","","101.16","","","","","","NA"
"2014-04-01 01:00","2014","04","01","01:00","**","2.5","","0.9","","78","","7","","21","","16.1","","101.15","","","","","","NA"
"2014-04-01 02:00","2014","04","01","02:00","**","2.1","","0.3","","84","","7","","18","","16.1","","101.09","","","","","","NA"
"2014-04-01 03:00","2014","04","01","03:00","**","2.3","","0.2","","84","","7","","15","","16.1","","101.06","","","","","","NA"
"2014-04-01 04:00","2014","04","01","04:00","**","3.0","","0.9","","76","","7","","13","","16.1","","101.03","","","","","","NA"
"2014-04-01 05:00","2014","04","01","05:00","**","2.8","","0.7","","78","","8","","17","","16.1","","100.96","","","","","","NA"
"2014-04-01 06:00","2014","04","01","06:00","**","2.7","","0.4","","80","","8","","18","","16.1","","100.93","","","","","","NA"
etc.
The data I would like to access is wind direction and wind speed. This should result in a direction vector of:
8
7
7
7
7
8
8
and a speed vector of:
17
21
18
15
13
17
18
I would ideally like two vector, one with direction and the other with speed. If I could obtain another vector with the time (just the hour value) that would be great as well.
Any help is always appreciated!

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Antworten (1)

Sara
Sara am 16 Apr. 2014
[~,~,a] = xlsread('file.xlsx','M18:M53');
for i = 1:length(a)
if(~isnumeric(a{i}))
a{i}=0;
elseif(isnan(a{i}))
a{i}=0;
end
end
a = cell2mat(a);
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Sara
Sara am 17 Apr. 2014
I don't get any error running the code for the cvs file you've posted. Just to make sure, is the matlab script in the same folder of the cvs file?
John
John am 22 Apr. 2014
I still had trouble running it, with the same error message, and the files were in the same directory. I ended up using just the syntax:
speed = xlsread('Wind.csv', M18:M350');
This just gave me the numerical values I needed. Thanks for the help Sara! :)

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