can anybody tell the matlab code for summation of multiple numbers?

N=200

Rx1 contains amplitude ai1,phase bi1(where 1<=i<=N)

Rx2 contains amplitude ai2,phase bi2(where 1<=i<=N)

Rx3 contains amplitude ai3,phase bi3(where 1<=i<=N) then

I=summation(ai1cosbi1)(here i lies 1 to N)

Q=summation(ai1sinbi1)(here i lies 1 to N)

finally

G=I+jQ(j is imaginary)

[vinod kumar govindu]

while using symsum function for summation of variables it showing error

Undefined function or method 'symsum' for input arguments of type 'double'.

Error in ==> cyl1 at 77

RR1=symsum(a(i)*cos(v1(i)),i,1,200);

what should i have to do for summation of double type values?

[Walter Roberson]

Even if you were to use

syms i

you would not be able to use symsum for that: you cannot use symsum to index into a variable.

 RR1 = sum(a(1:200) .* cos(v1(1:200)))

[vinod kumar govindu]

i am getting error while using above code

??? Attempted to access a(:,1); index out of bounds because numel(a)=1.

Error in ==> cyl1 at 78

RR1=sum(a(1:200) .* cos(v1(1:200)));

[vinod kumar govindu]

i want to plot complex signal

R1=RR1+RR2+RR3;

I1=IR1+IR2+IR3;

t=(0:1:100);

J=sqrt(-1);

complexreturn=R1+J*I1;

Re=real(complexreturn);

Im=imag(complexreturn);

plot(Re,Im,t,complexreturn);

grid on;

xlabel('time');

ylabel('amplitude');

title('time series');

after doing this it showing error

Warning: Imaginary parts of complex X and/or Y arguments ignored > In G at 114

help me to solve this?

[Walter Roberson]

You have

plot(Re,Im,t,complexreturn);

which is equivalent to two plots combined

plot(Re,Im)
plot(t,complexreturn)

Re and Im are both real-valued so that part of the plot would be okay.

t is real-valued so that part is okay.

complexreturn was constructed as complexreturn=R1+J*I1; where J = sqrt(-1) . So complexreturn is complex. You cannot plot complex data, only the real or imaginary portions or the abs() value, or the angle()

Answer 1

[Torsten]

https://www.mathworks.com/help/matlab/ref/sum.html

Best wishes

Torsten.