Matrix Manipulation of a specific column

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I have data in excel that is 17 columns by 4800 rows. The 17 columns represent different muscles, and the rows represent times they are "activated." For each column I need to know which numbers in that column are greater then 10 and what that number is. Once I find all those different numbers I need to sum them up. Just uncertain how to do this. Thank You!

Answers (1)

Hyeokjin Jho
Hyeokjin Jho on 27 Sep 2018
Assuming Data is the matrix that containing your data,
threshold = 10;
for i = size(Data,2)
pickedColumn = Data(:,i);
selectedNumbers{i} = pickedColumn(pickedColumn>threshold);
summedNumbers(i) = sum(selectedNumbers{i});
end
will work.
Numbers greater than 10 of column i is stored in selectedNumbers{i}, and summed value in summedNumbers(i)
  2 Comments
Brady Wayne Robinson
Brady Wayne Robinson on 27 Sep 2018
This doesn't seem to work. The error I get is Undefined function 'gt' for input arguments of type 'table'.
Error in Matlab_Homework1 (line 16) selectedNumbers{i} = pickedColumn(pickedColumn>threshold);
>>
Hyeokjin Jho
Hyeokjin Jho on 1 Oct 2018

Apparently Data seems to be a table instead of normal matrix.

threshold = 10;
for i = size(Data,2)
  pickedColumn = Data{:,i};
  selectedNumbers{i} = pickedColumn(pickedColumn>threshold);
  summedNumbers(i) = sum(selectedNumbers{i});
end

To extract data from table, you have to change Data(:,i) to Data{:,i}.

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