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numeric integral, symbolic function, whats wrong here?

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I wonder why matlab wont solve this integral for me. Is it the variable t that is the problem? I tried to use vpa in case that was the problem, but it does not look like that was the case eiter. Could someone please help me out?
clc
clear all
syms t;
rho = exp(sin(t));
theta = 2*exp(sin(t));
phi = 3*exp(sin(t));
rho_dot = diff(rho);
theta_dot = diff(theta);
phi_dot = diff(phi);
func = sqrt(rho_dot.^2+rho.^2*theta_dot.^2+ rho.^2*phi_dot.^2*(sin(theta)).^2)
vpafunc = vpa(func);
dist01 = integral(vpafunc, 0, 1)
Error messages (and cmd window) is as follows:
func =
(exp(2*sin(t))*cos(t)^2 + 4*exp(4*sin(t))*cos(t)^2 + 9*sin(2*exp(sin(t)))^2*exp(4*sin(t))*cos(t)^2)^(1/2)
Error using integral (line 82)
First input argument must be a function handle.
Error in Modreg_Ov1 (line 20)
dist01 = integral(vpafunc, 0, 1)

Accepted Answer

Stephan
Stephan on 19 Jan 2021
Edited: Stephan on 19 Jan 2021
clc
clear
syms t;
rho = exp(sin(t));
theta = 2*exp(sin(t));
phi = 3*exp(sin(t));
rho_dot = diff(rho);
theta_dot = diff(theta);
phi_dot = diff(phi);
func = sqrt(rho_dot.^2+rho.^2*theta_dot.^2+ rho.^2*phi_dot.^2*(sin(theta)).^2)
dist01 = vpa(int(func,0,1)) % Use int for symbolic integration

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