Whats wrong in those equations?

x=(0:0.5:80);
y1=(0.02049/0.4)*x;
y2=(0.59*60/(1+(1.331/(sqrt(0.0631*x/(74.45-x)))^3)));
y3=(0.59*60/(1+(1.331/(sqrt(0.0631*x/(74.45-x)))^3)))-(0.02049/0.4)*x;
y4=(0.02049/0.4)*x-(0.59*60/(1+(1.331/(sqrt(0.0631*x/(74.45-x)))^3)));
figure
plot(x,y1,'r')
hold on 
plot(x,y2,'c')
plot(x,y3,'g')
plot(x,y4,'b')
legend('y1','y2','y3','y4')
axis([0 80 0 3.5])

Hello Community,

I'm currently studying at the German Sport University Cologne and I'm an absolute newbie in Matlab. I need your help with those equations, Matlab gives me an Error using /

all I get is y1

Thank you very much!

Answer 1

[James Tursa]

Use element-wise operators (beginning with a dot) instead of matrix operators. E.g.,

y1=(0.02049/0.4)*x;
y2=(0.59*60./(1+(1.331./(sqrt(0.0631*x./(74.45-x))).^3)));
y3=(0.59*60./(1+(1.331./(sqrt(0.0631*x./(74.45-x))).^3)))-(0.02049/0.4)*x;
y4=(0.02049/0.4)*x-(0.59*60./(1+(1.331./(sqrt(0.0631*x./(74.45-x))).^3)));