troubles with trapz function

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hello
I Have a matrix that i have plotted on Matlab (it is the xls file attached). I need to find the area of the graph based on that data. I am using trapz function but it turns back with an error. Any help with that would be more than appreciated.
Kind regards
  1 Comment
Christos Papagrigoriou
Christos Papagrigoriou on 1 Mar 2020
Error using trapz (line 64)
Subscripting a table using linear indexing (one subscript) or multidimensional indexing (three or more subscripts) is not
supported. Use a row subscript and a variable subscript.
Error in stressplatform1 (line 42)
impulsemomentsquat1= trapz(x,y);
this is the exact eeror displayed. Would it be too much of a bother if I d ask to see what you did?
Cheers

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Accepted Answer

Star Strider
Star Strider on 1 Mar 2020
We likely took the same approach. There are several ways to access the data in table objects, as described in the documentation.
Try this:
T1 = readtable('stressplatformexp.xlsx');
x = T1{:,1};
y = T1{:,2};
A = trapz(x, y);
figure
patch([x; flipud(x)], [y; zeros(size(y))], 'g', 'FaceAlpha',0.5)
grid
text(6, 140, sprintf('Area = %.3f',A), 'HorizontalAlignment','center')
  2 Comments
Christos Papagrigoriou
Christos Papagrigoriou on 1 Mar 2020
u saved my degree luv ya
Star Strider
Star Strider on 1 Mar 2020
Thank you!
If my Answer helped you solve your problem, please Accept it!

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