How to use indexing format inside symsum function

clc;

close all;

clear all;

N=2;alpha=0.5

t=zeros(1,N)

l=1:N;

t(l)=solve(chebyshevT(N,2*x-1),x);

syms m

L=symsum(t(m),m,1,2)

[SUMIT]

After running the program i got

''Invalid indexing or function definition. When defining a function, ensure that the arguments are symbolic variables and the body of the function is a SYM expression. When indexing, the

input must be numeric, logical, or ':'.''

please help me out

[Paul]

Hi Sumit,

The code results in a different error because x is not defined. Is x supposed to be symbolic variable? What is the function chebyshev? It might be helpful if to explain what the code is trying to accomplish.

N=2;alpha=0.5;
t=zeros(1,N);
l=1:N;
t(l)=solve(chebyshevT(N,2*x-1),x);

Unrecognized function or variable 'x'.

syms m
L=symsum(t(m),m,1,2)

Answer 1

[Steven Lord]

If you want to sum the elements of a symbolic array, just use sum.

syms x
f = x.^(0:5)

f = 

s = sum(f)

s = 

Answer 2

[Walter Roberson]

It is never possible to index by a symbolic variable at the MATLAB level. (There are some cases in the internal symbolic computing engine where indexing by a symbolic variable is possible.)