How to use imported data with trapz( )
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Hi, I have imported two columns of a csv data file into Matlab and are contained in one table. The columns are labeled Times and DragForceN. I want to use them in trapz(x,y). My end goal here is to obtain the work done by drag. I keep getting an error message and I cannot figure out how to fix it. Any help would be appreciated.
x = importdata('Times.csv');
y = importdata('DragForceN');
dragWork_H13 = trapz(x,y)
4 Comments
Eric Sofen
on 19 Sep 2022
Your description "two columns...contained in one table" doesn't match with the code that shows imports to two separate variables, x and y.
It would also be helpful if you gave us the complete text of the error message. Are x and y the same size?
Johana Aguero-Fischer
on 19 Sep 2022
dpb
on 19 Sep 2022
Well, the error says importdata couldn't open the file; you didn't even get to the second step...it didn't say it couldn't find the file; so apparently there is such a file but it wasn't a valid text file as the .csv extension would suggest it should be.
But, we can't tell what went wrong -- attach the file so somebody can try to duplicate the issue/see what the file really does contain.
Johana Aguero-Fischer
on 19 Sep 2022
Answers (1)
T = readtable('https://in.mathworks.com/matlabcentral/answers/uploaded_files/1129920/H182%20Drag.csv') ;
x = T.(1) ;
y = T.(2) ;
% fill the NaN's in the data
x = fillmissing(x,'linear') ;
y = fillmissing(y,'linear') ;
%
trapz(x,y)
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