What is wrong with my matlab codes? ( MATLAB) please help me!

clear all;
clc

Vm=100;
Z=2;
angle_radians=pi*-0.5;

wt=0:0.01:(2*pi);
v=Vm*cos(wt);
Im=Vm/Z;
i=Im*cos((wt)-(angle_radians));
p=(v.*i);
pr=v*i*cos(angle_radians)*(1+cos(2*wt)); 
px=v*i*sin(angle_radians)*(1+sin(2*wt)); 


subplot(4,1,1);plot(wt,v,wt,i);title('v(t)=Vmcoswt,I(t)=Imcos(wt+-(-90)');

xlabel('time');
ylabel('voltage (volts) & Current (Amps)');

subplot(4,1,2);plot(wt,p);title('p(t)=v(t)i(t)');

xlabel('time (t)'); 
ylabel('power (Watts)');

subplot(4,1,3);plot(wt,pr);title('pr(t)');

xlabel('time (t)'); 
ylabel('pr(t)');

subplot(4,1,4);plot(t,i);title('px(t)');

xlabel('time (t)'); 
ylabel('px(t))');




grid;

I am trying to draw graphs about reactive power etc. What can be wrong with line 13 and matrix?

[Hyunuk Ha]

On the 11th, line, you should use .* (array operator) instead of * (matrix operator).

Please refer to detailed Doc. at :

https://www.mathworks.com/help/matlab/matlab_prog/array-vs-matrix-operations.html?searchHighlight=array%20operator%20matrix%20operator&s_tid=doc_srchtitle

Hope this helps,

Hyunuk

[Santa Fe]

thank you so much!

Answer 1

[Dr. Pemendra Kumar Pardhi]

Please replace the all * with .* for element wise product

and in line no 31, you neet to replace t with wt