"Subscripted assignment dimension mismatch"
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Hello,
Here is part of the code in which I can't avoid the following error: "Subscripted assignment dimension mismatch" at line 115. I do not have this error and the code runs fine, when I take away the main loop for the incremental load and instead have just one predefined value. If anyone can help, I will highly appreciate! If necessary I will send the whole code by mail.
Regards, Pavlin
CODE
for increment = 1:incmax
q_total=q_total+q_incr;
K(beam_DOFs,beam_DOFs)=0;
F(beam_DOFs,1)=0;
for el_y=1:beam_el_y
y1=(W/beam_el_y)*(el_y-1);
y3=y1+W/beam_el_y;
for el_x=1:beam_el_x
x1=(L/beam_el_x)*(el_x-1);
x3=x1+L/beam_el_x;
i1=(beam_el_y+1)*(el_x-1)+el_y;
i2=i1+beam_el_y+1;
el_DOFs=[2*i1-1; 2*i1 ; 2*i2-1 ; 2*i2; 2*i2+1; 2*i2+2; 2*i1+1; 2*i1+2];
Em=(E_el(el_x,el_y)/(1-nu^2))*[1 nu 0
nu 1 0
0 0 (1-nu)/2];
Ke=Q4_stiffness(x1,x3,y1,y3,Em,T);
K(el_DOFs,el_DOFs)=K(el_DOFs,el_DOFs)+Ke;
end
end
all_DOFs=1:beam_DOFs;
fixed_DOFs_y=beam_DOFs;
fixed_DOFs_x=1:2:2*(beam_el_y+1);
fixed_DOFs=union(fixed_DOFs_x,fixed_DOFs_y);
free_DOFs=setdiff(all_DOFs,fixed_DOFs);
F(2,1)=-q_total;
U(free_DOFs,:)=K(free_DOFs,free_DOFs)\F(free_DOFs,:);
U(fixed_DOFs,:)=0;
ver_DOFs_top_side=2*(beam_el_y+1):2*(beam_el_y+1):beam_DOFs;
U(ver_DOFs_top_side,:);
ver_DOFs_top_side2=ver_DOFs_top_side;
ver_DOFs_top_side2(:,end)=[];
U(2,1);
U_tot=U_tot+U(2,1);
for el_y=1:beam_el_y
y1=(W/beam_el_y)*(el_y-1);
y3=y1+W/beam_el_y;
for el_x=1:beam_el_x
x1=(L/beam_el_x)*(el_x-1);
x3=x1+L/beam_el_x;
i1=(beam_el_y+1)*(el_x-1)+el_y;
i2=i1+beam_el_y+1; % i2=(DCB_y+1)*el_x+el_y;
el_DOFs=[2*i1-1; 2*i1 ; 2*i2-1 ; 2*i2; 2*i2+1; 2*i2+2; 2*i1+1; 2*i1+2];
Em=(E_el(el_x,el_y)/(1-nu^2))*[1 nu 0
nu 1 0
0 0 (1-nu)/2];
el_displ=U(el_DOFs);
el_stress=zeros(3,8);
el_strain=zeros(3,8);
[el_stress el_strain]=Q4_stress(x1,x3,y1,y3,Em,el_displ);
Sigma_xx(el_x,el_y)=el_stress(1,1);
Sigma_yy(el_x,el_y)=el_stress(2,1);
Sigma_xy(el_x,el_y)=el_stress(3,1);
x(el_x,el_y)=x1; % For the mesh plot
y(el_x,el_y)=y1; % For the mesh plot
Sigma_xx_tot(el_x,el_y) = Sigma_xx_tot(el_x,el_y) + Sigma_xx(el_x,el_y);
Sigma_yy_tot(el_x,el_y) = Sigma_yy_tot(el_x,el_y) + Sigma_yy(el_x,el_y);
Sigma_xy_tot(el_x,el_y) = Sigma_xy_tot(el_x,el_y) + Sigma_xy(el_x,el_y);
S11 = 2*Sigma_xx_tot(el_x,el_y)/3 - Sigma_yy_tot(el_x,el_y)/3;
S22 = 2*Sigma_yy_tot(el_x,el_y)/3 - Sigma_xx_tot(el_x,el_y)/3;
S12 = Sigma_xy_tot(el_x,el_y);
Sigma_von_Mises = sqrt(3*(S11^2+S22^2+3*S12^2)/2);
if Sigma_von_Mises > Sigma_y;
E_el(el_x,el_y)=E/10;
else
E_el(el_x,el_y)=E;
end
end
end
last_x=zeros(1,beam_el_y);
LINE 115 last_x(1,:)=x(end,:)+L/beam_el_x;
x=[x;last_x]; x=[x,x(:,end)]; last_y=zeros(1,beam_el_y); last_y(1,:)=y(end,:); y=[y;last_y]; y=[y,y(:,end)+W/beam_el_y];
0 Comments
Accepted Answer
Matt Fig
on 15 Nov 2012
Edited: Matt Fig
on 15 Nov 2012
This error occurs, much like the message tells you, when you try to put the wrong number (or shape) of items into an array. Here is a simple example:
H = zeros(6);
try
H(:,1) = rand(2,3); % Wrong shape.
catch
fprintf('%s\n',lasterr)
end
try
H(:,1) = rand(7,1); % Wrong number.
catch
fprintf('%s\n',lasterr)
end
H(:,1) = rand(6,1) % Correct shape and number!
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