how to find symprod for double type values if i take it as seperate function. I am getting this error Undefined function 'symprod' for input arguments of type 'double'. Error in practise (line 5) y=symprod(x,j,1,3);

function y= practise(k)
 k=2;
 x=(rand(4)).*k;
 syms j;
 y=symprod(x,j,1,3);
end

Answer 1

[Birdman]

Change this line

x=(rand(4)).*k;

to

x=sym(rand(4).*k);

[MAMATHA YADAVALLI]

it's getting error like Error using sym/symprod (line 52) Cannot compute the product with respect to '0+1i'. The product index must be a symbolic variable.

Error in practise (line 5) y=symprod(x,j,1,3);

[Birdman]

Yes, that is true. What did you try to do so that you get this error? Show your code.

[MAMATHA YADAVALLI]

function y= practise(k)
 x=sym(rand(4).*k);
 syms j;
 y=symprod(x,j,1,3);
end

[Birdman]

Ok, this one works well for me. MATLAB can interpret j if you do not define it symbolically but since you do it, there should be no problem.

[MAMATHA YADAVALLI]

this function file i want to use in my main program

clc;clear all;
k=2;
hh=practise(k);

[MAMATHA YADAVALLI]

it's working thank you

[Birdman]

Ok, use:

 j=sym('j')

Answer 2

[Steven Lord]

You want to compute the product of the elements of x? If that's the case, don't use symprod. There are no symbolic calculations necessary. Just use the prod function instead.