Loop for matrix summation
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Hello, sorry if my question is stupid, I am a beginner in matlab
I would like to do a 3*3 matrix sumation (element by element). More in detail: I am working with a matlab fuction which output is a 3*3 matrix, the input is 3 column data (strr1,dpr1and rkr1). Then I would like to divide each matrix obtained from the input (280 elements, so I have 280 3*3 matrix) by a scalar, and finally, from that result I would like to sume each matrix to get a single 3*3 matrix (the result of the summation of all matrix calculated by the function). Next, a small script about my problem
Thanks for your attention
strr1=(tw1r1(:,12)); %%input1
dpr1=(tw1r1(:,14)); %%input2
rkr1=(tw1r1(:,16)); %%input3
mtr11w1s=zeros(3,3) %% I created this matriw for storing the final summation
for rr1=1:length(strr1) %%% loop for calculating the 280 3*3 matrix from thre 3 inputs
mtr1=SDR2MT(strr1( rr1),dpr1( rr1),rkr1( rr1)) %%%% Result: 280 3*3 matrix
mtr1n=mtr1/length(tw1r1) %%%%Escalar division for each element of the 3*3 matrix
for z=1:length(mtr1n) %%%% Here I try to do a loop for doing the summation of 280 3*3 matrix
mtr11w1s= mtr11w1s+mtr1n(z)
end
end
采纳的回答
DGM
2021-4-4
I'm not sure what tw1r1 is supposed to be. I'm going to substitute something there.
mytestnumber=37;
mtr11w1s=zeros(3,3);
for rr1=1:numel(strr1)
%mtr1=SDR2MT(strr1( rr1),dpr1( rr1),rkr1( rr1)) %%%% Result: 280 3*3 matrixm
mtr1=ones(3); % i don't have SDR2MT, so this is just a dummy
mtr1n=mtr1/mytestnumber;
for z=1:numel(mtr1n)
%mtr11w1s=mtr11w1s+mtr1n(z); % you sure you don't mean to be doing
mtr11w1s(z)=mtr11w1s(z)+mtr1n(z); % something like this?
end
end
mtr11w1s
I'm still not really sure if this is doing what you intend it to do. Do you have a written expression for the summation you're trying to do?
Also, as a tip:
a=rand(3,3); [length(a) numel(a)]
shows that if you want to step through all the linear indices of a 2D array, you shouldn't be using length()
ans =
3 9
3 个评论
Perez Danny
2021-4-4
DGM
2021-4-4
I take it that the results are as you expect?
Perez Danny
2021-4-4
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