How to delete a column with a specific value
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In my case i would like to delete specific columns where for example the minimum value is 2e11;
This code below doesn't work, i get this error: Matrix index is out of range for deletion.
Error in reactionforce_script (line 16) reactionforce(reactionforce(2:end,:) < thresholdmin | reactionforce(2:end,:) > thresholdmax, :) = []
code :
load ('Y:\Spoormodel\06\reactionforce2.mat');
%reactionforce2 = removevars(reactionforce, 3:2:end);
reactionforce2 = reactionforce;
reactionforce(4:2:end,:) = [];
reactionforce(:,3:2:end) = [];
%reactionforce(:,35:end) = []; %verwijderen van kolommen zonder waarde
reactionforce(1,:) = [];
reactionforce = table2array(reactionforce);
% thresholdmin = 2e11;
% thresholdmax = 2e30;
% reactionforce(reactionforce(2:end,:) < thresholdmin | reactionforce(2:end,:) > thresholdmax, :) = []
%
reactionforce = array2table(reactionforce);
time = table2array(reactionforce(2:end,1));
data = reactionforce(2:end,2:end);
data = table2array(data(1:end,1:end));
plot (time,data);
3 个评论
madhan ravi
2018-11-5
Provide sample data
Jesse
2018-11-5
madhan ravi
2018-11-5
attach your .mat file
采纳的回答
Guillaume
2018-11-5
Error in reactionforce_script (line 16)
reactionforce(reactionforce(2:end,:) < thresholdmin | reactionforce(2:end,:) > thresholdmax, :) = []
Well, yes that line is never going to work. If that line is meant to delete all rows for which any value in any columns but the first is outside the boundary, then:
reactionforce(any(reactionforce(2:end,:) < thresholdmin | reactionforce(2:end,:) > thresholdmax), :) = [];
6 个评论
Guillaume
2018-11-6
Forgot to tell any to operate across the columns:
reactionforce(any(reactionforce(2:end,:) < thresholdmin | reactionforce(2:end,:) > thresholdmax, 2), :) = [];
However, I've just noticed to you convert your table to a matrix just to perform the deletion and then convert back to a table. That's a complete waste of time. You need to learn to manipulate tables directly.
To operate directly on the table, it's nearly the same syntax except you use {} to access the content of the table:
reactionforce(any(reactionforce{2:end,:} < thresholdmin | reactionforce{2:end,:} > thresholdmax, 2), :) = [];
Jesse
2018-11-6
Guillaume
2018-11-7
I was a bit puzzled by your question as you asked about deleting columns but your original code deleted rows. So it's definitively columns you want to delete?
I'm not sure what " if the minimum AND maximum value is between a range" means. Do you mean you want to delete a column (which are called variables in a table) if all values are within the range? In which case:
reactionforce(all(reactionforce{2:end, :} >= thresholdmin & rectionforece{2:end, :} <= thresholdmax, 1), :) = [];
Note that since you're now looking at all values along the rows for a column, you use all(xxx, 1) instead of all(xxx, 2) (or any(xxx, 1) instead of any(xxx, 2))
Jesse
2018-11-7
madhan ravi
2018-11-7
+1 perfecto @Guillaume
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