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What is wrong with my code

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Daniel Sode
Daniel Sode on 20 Jul 2020
Answered: Dinesh Yadav on 23 Jul 2020
N = 16;
E = 200e9; % Young Modulus (Pa)
b = 0.1; % Top width (m^2)
a = 0.025; % Bottom width (m^2)
L = 1.0; % Length (m)
rho = 77e3; % Force density (N/m^3)
Le = L./N;
ff = 0;
for i = 1:N
w(i)=(((i-0.5).*Le)*((b-a)./L))+a; %Calculates avg width (m)
A(i)=w(i).^2; %Calculates element area (m^2)
k(i) = A(i)*E/Le; %Local Stiffness Matrix constact
f(i) = ff*A(i)*le*rho/2; %Local Force Matrix constant
end
KG = zeros(N+1,N+1)
FG = zeros(N+1,N+1)
for ii = 1:N
KG(ii:ii+1,ii:ii+1)=KG(ii:ii+1)+k(i);
FG(ii:ii+1,ii:ii+1)=FG(ii:ii+1)+f(i);
end
Displacement = inv(KG)*FG;
plot(N,Displacement,'b');
hold on
plot(N,Displacement,'*','color','r')
ylabel('end deflection in mm');
xlabel('no of element')

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KSSV
KSSV on 20 Jul 2020
The first error is solved....
For the second you need to check your logic.....you are trying to save 1X2 array in a 2X2 matrix.
Daniel Sode
Daniel Sode on 20 Jul 2020
I redid the code and am getiing this error
Unable to perform assignment because the left and right sides have a different number of elements.
Error in Termproject (line 10)
w(i)=(((i-0.5).*Le)*((b-a)./L))+a; %Calculates avg width (m)
Daniel Sode
Daniel Sode on 20 Jul 2020
N = linspace(1,16,100);
E = 200e9; % Young Modulus (Pa)
b = 0.1; % Top width (m^2)
a = 0.025; % Bottom width (m^2)
L = 1.0; % Length (m)
rho = 77e3; % Force density (N/m^3)
Le = L./N;
ff = 0;
for i = 1:N
w(i)=(((i-0.5).*Le)*((b-a)./L))+a; %Calculates avg width (m)
A(i)=w(i).^2; %Calculates element area (m^2)
k(i) = (A(i)*E/Le);%*[1 -1;-1 1]; %Local Stiffness Matrix constact
f(i) = (ff*A(i)*Le*rho/2);%*[1;1]; %Local Force Matrix constant
end
KG = zeros(N+1,N+1);
FG = zeros(N+1,N+1);
for i = 1:N
KG(i,i) = KG(i,i) + k(i);
KG(i,i+1) = KG(i,i+1) - k(i);
KG(i+1,i) = KG(i+1,i) - k(i);
KG(i+1,i+1) = KG(i+1,i+1) + k(i);
FG(i,1) = FG(i,1) + f(i);
FG(i+1,1) = FG(i+1,1) +f(i)
end
Displacement = inv(KG)*FG;
plot(N,Displacement,'b');
hold on
plot(N,Displacement,'*','color','r')
ylabel('end deflection in mm');
xlabel('no of element')

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Answers (1)

Dinesh Yadav
Dinesh Yadav on 23 Jul 2020
Change to the following code
len = length(N) %N is 1x100 you want i to go from 1 to 100 therefore change to length(N) instean of N
for i = 1:len
w(i)=(((i-0.5)*Le(i))*((b-a)/L))+a; % Le is also 1x100 you want to take one elsment at a time use Le(i)
A(i)=w(i).^2; %
k(i) = (A(i)*E/Le(i));%*[1 -1;-1 1]; %
f(i) = (ff*A(i)*Le(i)*rho/2);%*[1;1]; %
end
KG = zeros(len+1,len+1);
FG = zeros(len+1,len+1);
for i = 1:len

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