MATLAB: Are the lines not showing up on the graphs

graph

g=9.81;
Ta=10;
mA=20;
for i=1:100
M=(i-1)*(30/99);
mB=4.05;
mC=M;
mD=M;
JC=0.005*M;
JD=JC;
JA=0.8055;
A=[mA 0 -1 1 0 0 0; (5*JA) 0 0.2 0 0 0 0; (10*JC) 0 0 -0.1 0 0.1 0; 0 mD 0 0 -1 -1 -1; 0 (10*JD) 0 0 0 -0.1 0.1; 0 mB 0 0 -1 0 0; -0.5 1 0 0 0 0 0];
B=[0; Ta; 0; (-mD*g); 0; (-mB*g); 0];
x=inv(A)*B;
aA(i)=x(1); aB(i)=x(2); FA(i)=x(3); TA(i)=x(4); TB(i)=x(5); TC(i)=x(6); TD(i)=x(7);
end
Mvector=linspace(0,30,100);
plot(Mvector, aA(i),'g',Mvector,aB(i),'b-.');
title('Acceleration');
legend('Disk A','Mass B');
xlabel('M (kg)');
ylabel('Acceleration (m/s^2)');
pause
plot(Mvector,aA(i),'g',Mvector,aB(i),'b-.');
title('Acceleration');
legend('Disk A','Mass M');
xlabel('M (kg)');
ylabel('acceleration (m/s^2)');
pause
plot(Mvector, FA(i),'k');
title('Plot 3');
xlabel('M (kg)');
ylabel('FA (N)');
pause
plot(Mvector,TA(i),'g',Mvector,TB(i),'b-.');
title('Plot 4');
legend('Cable A','Cable B');
xlabel('M (kg)');
ylabel('Tension (N))');
pause
plot(Mvector,TA(i),'g',Mvector,TC(i),'b:',Mvector,TD(i),'r-.');
title('Plot 5');
legend('Cable A','Cable C','Cable D');
xlabel('M (kg)');
ylabel('Tension (N)');
pause
plot(Mvector,FA(i)/(mA*g),'k');
title('Plot 6');
xlabel('M (kg)');
ylabel('mu');

Best Answer

You are only plotting one point (that being the last point) and it is not possible to plot lines with only one point.
Try this: 
Mvector=linspace(0,30,100);
figure
plot(Mvector, aA,'g',Mvector,aB,'b-.');
title('Acceleration');
legend('Disk A','Mass B');
xlabel('M (kg)');
ylabel('Acceleration (m/s^2)');
% pause




figure
plot(Mvector,aA,'g',Mvector,aB,'b-.');
title('Acceleration');
legend('Disk A','Mass M');
xlabel('M (kg)');
ylabel('acceleration (m/s^2)');
% pause
figure
plot(Mvector, FA,'k');
title('Plot 3');
xlabel('M (kg)');
ylabel('FA (N)');
% pause
figure
plot(Mvector,TA,'g',Mvector,TB,'b-.');
title('Plot 4');
legend('Cable A','Cable B');
xlabel('M (kg)');
ylabel('Tension (N))');
% pause
figure
plot(Mvector,TA,'g',Mvector,TC,'b:',Mvector,TD(i),'r-.');
title('Plot 5');
legend('Cable A','Cable C','Cable D');
xlabel('M (kg)');
ylabel('Tension (N)');
% pause
figure
plot(Mvector,FA/(mA*g),'k');
title('Plot 6');
xlabel('M (kg)');
ylabel('mu');
Also, you were overplotting each new plot on the previous one, erasing the previous one. Since it appears you want them on separate figures, this slightly revised code does that. If you want to plot all of them on the sane axes, use the hold function.
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