Error when trying to use [I,m]=quad(fun, a, b, tol)

Im trying to use the following line [I,m]=quad(g,0,1,1.0e-6) to get the number of nodes used and the aproximate value of the integral between 0 and 1 of g, which is g = exp(1).^x/(1+exp(1).^(2.*x)). but whenever I try to call the quad expression, I get the following:

Error using fcnchk (line 107)

If FUN is a MATLAB object, it must have an feval method.

Error in quad (line 57)

f = fcnchk(funfcn);

Answer 1

[Pratyush Roy]

Hi,

If x is a symbolic variable, then the function g becomes a symbolic expression. In such cases, you should consider converting the expression to a function handle using the matlabFunction command.

You can also use the following code snippet for evaluating the nodes and approximate value of the integral

g = @(x)exp(1).^x./(1+exp(1).^(2.*x)) % "./" stands for element-wise division  
[I,m]=quad(g,0,1,1.0e-6);

Hope this helps!