MATLAB: I can’t figure out why I am getting the error message Matrix dimensions must agree.

errorMATLABmatrix

clc;
k=48000;
m=1200;
c=[3000:1000:10000];
w=sqrt(k/m);
E=c/(2*sqrt(m*k));
a=sqrt(1-E.^2)*w;
b=E/(sqrt(1-E.^2));
f0=9000/100;
d=E*w;
t=[0:0.05:10];
x=f0-f0.*exp(-d.*t).*cos(a.*t)-(f0*b).*exp(-d.*t).*sin(a.*t);
plot(t,x);
ylabel('Frequency of Suspension');
xlabel('Time (s)');
title('Frequency of Car Suspension')

Best Answer

The problem is that ‘c’ and everything you calculate from it are (1x8) vectors and ‘t’ is a (201x1) vector. Your ‘x’ assignment works if you transpose ‘a’ and ‘d’ to column vectors:
a=sqrt(1-E'.^2)*w;
d=E'*w;
It then plots a family of curves.
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