# hi I have problem do not draw curve

5 views (last 30 days)
We have circuit RLC.
g=Um.e^(-L/R t).cos⁡(2π/T t+φ)
Ecos(wt)
///////////////
This is our code:
w=2*pi*50;
E=5;
l=100e-6;
c=200e-6;
R=10;
t=0:0.01:300;
s=l/R;
T=2*pi*sqrt(l*c);
q=1/c*w;
v=(tan((l*w-q)/R))^-1;
g=E*cos(w*t)*exp(-s*t)*cos((2*pi/T)+v);
plot(t,g)
........
Error in Untitled (line 11)
g=E*cos(w*t)*exp(-s*t)*cos((2*pi/T)+v);

madhan ravi on 24 Dec 2018
Edited: madhan ravi on 24 Dec 2018
w=2*pi*50;
E=5;
l=100e-6;
c=200e-6;
R=10;
t=0:0.01:300;
s=l/R;
T=2*pi*sqrt(l*c);
q=1/c*w;
v=(tan((l*w-q)/R))^-1;
g=E.*cos(w.*t).*exp(-s.*t).*cos((2.*pi./T)+v); % dots between operators (element-wise operation)
plot(t,g)
xlim([0 1]) % reduce the axis limit since it's stuffed so close

Image Analyst on 24 Dec 2018
This "works"
w=2*pi*50;
E=5;
l=100e-6;
c=200e-6;
R=10;
t = 0:0.01:300;
s=l/R;
T=2*pi*sqrt(l*c);
q=1/c*w;
v=(tan((l*w-q)/R))^-1;
g=E*cos(w*t) .* exp(-s*t) .*cos((2*pi/T)+v);
plot(t,g)
caption = sprintf('Plot of %d points', length(t));
title(caption, 'FontSize', 20);
Though with 30,0001 points, and a monitor that is only 1980 pixels across, the plot looks solid. If you reduce the number of points, you'll see something but it won't be the original signal - it will be a subsampled version and could be very deceptive to look at that and think that is what the curve looks like for an infinite number of points.

belal hariz belgacem on 24 Dec 2018
Thank you