Are there any examples that demonstrate how to read a comma-delimited ASCII file that contains missing data?
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I have a file called 'myfile.dat' which contains the following data:
date,time,current,voltage,power
12/01/60,3:56,1,2,3
12/01/61,3:57,2,4,6
12/01/67,3:58,3,,9
12/01/63,3:59,4,8
12/01/64,4:00,5,10,12
I am interested in reading the current, voltage, and power values from the file. As you can see, some data is missing so I would like to fill these spots with a zero. I would like to know what would be the best command to read such data in MATLAB.
Accepted Answer
MathWorks Support Team
on 3 Nov 2021
Edited: MathWorks Support Team
on 17 Nov 2021
The TEXTSCAN command can be used to read formatted data into MATLAB. TEXTSCAN reads data from an open text file identified by a file identifier into a cell array. You can use the command as follows:
fid = fopen('myfile.dat')
C = textscan(fid,'%s %s %d %d %d','HeaderLines',1,'Delimiter',',','EmptyValue',0)
current = C{3};
voltage = C{4};
power = C{5};
fclose(fid);
If there is missing data, TEXTSCAN will replace the missing numeric values with 0. This is a configurable property and can be changed using the EmptyValue parameter in TEXTSCAN.
For more general information on how to read data files into MATLAB, see the following link:
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