Building a matrix inside a for loop
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Hi guys, can anyone help me with this please. Thanks.
So i have this Excel file. I filtered a column and then did some operations on the filtered data .
in the end, I wanna create a new matix, A, with the following characteristics. The matrix should have dimension: partID rows* 5 columns. First colum should contain the partID number (from 3 to 15), second column should contain the value of M associated with the partID, third column S, fourth m and fifth s.
how do i build A inside the cycle?
6 个评论
Turlough Hughes
2020-5-15
Can you share the file?
Murstoe
2020-5-15
Turlough Hughes
2020-5-23
Murstoe, it's bad form to remove your question after being given an answer. Can you put it back?
Stephen23
2020-5-23
Original question from Google Cache:
"Building a matrix inside a for loop"
Hi guys, can anyone help me with this please. Thanks.
So i have this Excel file. I filtered a column and then did some operations on the filtered data .
in the end, I wanna create a new matix, A, with the following characteristics. The matrix should have dimension: partID rows* 5 columns. First colum should contain the partID number (from 3 to 15), second column should contain the value of M associated with the partID, third column S, fourth m and fifth s.
how do i build A inside the cycle?
xlsData = xlsread('PartS_all.csv');
partID=xlsData(:,4);
for partID=3:15
tenpm=xlsData(xlsData(:,4)==partID,:);
part=sortrows(tenpm, 2); %Sort second column
M(partID)=mean(part(:,8));
S(partID)=std(part(:,8));
m(partID)=mean(part(:,11));
s(partID)=std(part(:,11));
A=
end
Murstoe
2020-5-23
Rena Berman
2020-6-1
(Answers Dev) Restored edit
采纳的回答
Turlough Hughes
2020-5-16
编辑：Turlough Hughes
2020-5-16
You could do it as follows:
xlsData = xlsread('PartS_all.xlsx');
partID = xlsData(:,4);
uPartID = unique(partID).'; % Unique part IDs
% Preallocate space
c = 0;
A = zeros(numel(uPartID),5);
for currPartID = uPartID
c = c+1;
part = xlsData(xlsData(:,4) == currPartID,:); %edit
A(c,:) = [currPartID mean(part(:,8)) std(part(:,8)) mean(part(:,11)) std(part(:,11))];
end
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