MATLAB: Error using mtimes

errormatrix

This is the script I am currently processing through MATLAB however it keeps returning me an error that says : ??? Error using ==> mtimes Inner matrix dimensions must agree.
Error in ==> Complexmodel at 12 T1=((elevator_mass+load_mass1)*g+X)*a;
My script:
g=9.81;
elevator_mass=1000;
load_mass1=1500;
load_mass2=2000;
load_mass3=2500;
safe_load=4500;
u=0.6:1:1.6;
a=0:1:10;
safty(1:11)=safe_load;
X=3.*u.^2;
xlabel_information='Elevator acceleration';
T1=((elevator_mass+load_mass1)*g+X)*a;
T2=((elevator_mass+load_mass2)*g+X)*a;
T3=((elevator_mass+load_mass3)*g+X)*a;
plot(a,T1,'b-o',a,T2,'g-o',a,T3,'k-o',a,safty,'.');
xlabel(xlabel_information)
ylabel('Cable Tension')
title('Tension vs Acceleration');
legend('load mass 1','load mass 2','load mass 3','Safe load');
[EDITED, JSimon, 09-Oct-2011 16:19 UTC] Code formatted – please do this by your own, see Markup help

Best Answer

You could use the debugger to locate the problem:
dbstop if error
Now MATLAB stops, if the error occurs and you can inspect the dimensions:
In: T1=((elevator_mass+load_mass1)*g+X)*a;
((elevator_mass+load_mass1)*g+X  => [1 x 2]
a => [1 x 11]
Of course the multiplication is not possible.
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