Perform for loop and carry out calculation separately
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Dear community,
I´m once again asking for your help!
As visible in the code below, I´m trying to perform a for loop in steps of 1:1:823´543 (which corresponds to the length of vector a_1_7a. What I ultimately want to achieve, is that these c- and D-factors are calculated for every single value of the given range (which means that the related value is to be extracted from a previously defined vector, in this case depth_7a_p). After calculating 823´543 values for c and D a related number (823543) of matrices V_7a_p and vectors S_7a_p shall be created. Finally, the same amount of gamma factor vector is to be calculated and extracted from the for loop.
For some reason I don´t understand, this doesn´t work. Hopefully you´re able to help me.
Greetings
David
for n=1:1:length(a_1_7a)
c_1_2=width*G./depth_7a_p(n,1).*10^3;
c_2_3=width*G./depth_7a_p(n,2).*10^3;
c_3_4=width*G./depth_7a_p(n,3).*10^3;
c_4_5=width*G./depth_7a_p(n,4).*10^3;
D_1=pi^2*E_0*width.*depth_7a_p(n,1)./(span).*10^-3;
D_2=pi^2*E_0*width.*depth_7a_p(n,2)./(span).*10^-3;
D_3=pi^2*E_0*width.*depth_7a_p(n,3)./(span).*10^-3;
D_4=pi^2*E_0*width.*depth_7a_p(n,4)./(span).*10^-3;
D_5=pi^2*E_0*width.*depth_7a_p(n,5)./(span).*10^-3;
a_3_7a(n)=0;
V_7a_p=[(c_1_2+D_1)*a_1_7a(n) -c_1_2*a_2_7a(n) 0 0 0; -c_1_2*a_1_7a(n) (c_1_2+c_2_3+D_2)*a_2_7a(n) -c_2_3*a_3_7a(n) 0 0; 0 -c_2_3*a_2_7a(n) (c_2_3+c_3_4+D_3)*a_3_7a(n) -c_3_4*a_4_7a(n) 0; 0 0 -c_3_4*a_3_7a(n) (c_3_4+c_4_5+D_4)*a_4_7a(n) -c_4_5*a_5_7a(n); 0 0 0 -c_4_5*a_4_7a(n) (c_4_5+D_5)*a_5_7a(n)];
S_7a_p=[-c_1_2*(a_2_7a(n)-a_1_7a(n));-c_2_3*(a_3_7a(n)-a_2_7a(n))+c_1_2*(a_2_7a(n)-a_1_7a(n));-c_3_4*(a_4_7a(n)-a_3_7a(n))+c_2_3*(a_3_7a(n)-a_2_7a(n));-c_4_5*(a_5_7a(n)-a_4_7a(n))+c_3_4*(a_4_7a(n)-a_3_7a(n));c_4_5*(a_5_7a(n)-a_4_7a(n))];
gamma_7a_1=(V_7a_p).^-1.*S_7a_p;
end
2 个评论
Rik
2020-11-16
You are overwriting most variables in your loop, instead of indexing them.
The variable names look like you are using many numbered variables, which is generally a bad idea. You might be tempted to try to generate the variable names at runtime, instead of using indexing. You are also hiding a lot of information because you don't use descriptive variable names or comments.
Why don't you first try to get your code working and optimize it before you throw almost a million iterations at it. Can you try to find a way to vectorize your code?
回答(1 个)
Shadaab Siddiqie
2020-11-19
From my understanding you want to accelerate your code. Please vectorize your code. This reference might help you.
2 个评论
Shadaab Siddiqie
2020-11-20
编辑:Shadaab Siddiqie
2020-11-20
You can still vectorize it. One example would be:
c_1_2=width*G./depth_7a_p_1.*10^3;
c_2_3=width*G./depth_7a_p_2.*10^3;
c_3_4=width*G./depth_7a_p_3.*10^3;
c_4_5=width*G./depth_7a_p_4.*10^3;
%insted of above code you can convert depth_7a_p_1,depth_7a_p_2,..,depth_7a_p_4 into a matrix
C = width*G./D.*10^3;
% Here D = [depth_7a_p_1 ; depth_7a_p_2 ;depth_7a_p_3 ;depth_7a_p_4]
Dont create depth_7a_p_1,depth_7a_p_2,..,depth_7a_p_4 at all create D directly from depth_7a_p.
另请参阅
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