How can I loop into a matrix?

조회 수: 1 (최근 30일)
saheed
saheed 2014년 3월 7일
댓글: saheed 2014년 3월 8일
I have six values of E and v which are entries of Matrix s of the structure; s=[1/E -v/E 0; v/E 1/E 0; 0 0 2*(1+v)/E]
the six matrices of s formed are the entry into the matrix S; S=[s(1) s(2) s(3) s(4) s(5) s(6)]
How can I loop the values of E and v into the matrix s?
  댓글 수: 2
Image Analyst
Image Analyst 2014년 3월 7일
Are E and V row matrices or column matrices? What do you think the size of little should be? And what about big S? Can you give a numerical example?
saheed
saheed 2014년 3월 7일
E and v are coulmn matrices and the size of matrix s is 3 by 3 while size of matrix S is 3 by 18 since we have 6 s matrices in the column space of matrix S. for example,
s(i)=[1/E(i) -v(i)/E(i) 0; v(i)/E(i) 1/E(i) 0; 0 0 2*(1+v(i))/E(i)]
where i=1,2,..,6 for each value of E and v

댓글을 달려면 로그인하십시오.

채택된 답변

Mischa Kim
Mischa Kim 2014년 3월 7일
I assume you are trying to do something like
for ii = 1:6
S{ii} = [1 -v(ii) 0; v(ii) 1 0; 0 0 2*(1+v(ii))]/E(ii);
end
Note that S is a cell array, so your first matrix (your s(1)) would be accessed as S{1}.
  댓글 수: 3
Mischa Kim
Mischa Kim 2014년 3월 7일
Yep, either way would work. My thinking was that Saheed wanted to access the inidividual matrix elements of S = [s(1) s(2) s(3) s(4) s(5) s(6)] with something that resembled that format.
saheed
saheed 2014년 3월 8일
Thanks Patrick and Mischa. Patrick code works fine and suit my need.

댓글을 달려면 로그인하십시오.

추가 답변 (1개)

Patrik Ek
Patrik Ek 2014년 3월 7일
편집: Patrik Ek 2014년 3월 7일
I think that you need to loop here, since Matlab do normally not implement any operations that you reuqests. I mean
[vector, 0; 0, vector]
gets the size 2 x length(vector)+1
try something like
s = [];
for k = 1:length(E)
s_temp= [1/E(k) -v(k)/E(k) 0; v(k)/E(k) 1/E(k) 0; 0 0 2*(1+v(k))/E(k)];
s = [s,s_temp];
end
I may have some syntax errors since the code is not tested, but I guess it should work. Of course you can also preallocate vectors and so as well to speed up the code, if that is necessary.
Good luck!

카테고리

Help CenterFile Exchange에서 Loops and Conditional Statements에 대해 자세히 알아보기

태그

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by