## Functions of one Variable

Loadable Function: [v, ier, nfun] = quad (f, a, b, tol, sing)
Integrate a nonlinear function of one variable using Quadpack. The first argument is the name of the function to call to compute the value of the integrand. It must have the form

```y = f (x)
```

where y and x are scalars.

The second and third arguments are limits of integration. Either or both may be infinite.

The optional argument tol is a vector that specifies the desired accuracy of the result. The first element of the vector is the desired absolute tolerance, and the second element is the desired relative tolerance. To choose a relative test only, set the absolute tolerance to zero. To choose an absolute test only, set the relative tolerance to zero.

The optional argument sing is a vector of values at which the integrand is known to be singular.

When called with two arguments, this function allows you set options parameters for the function `quad`. Given one argument, `quad_options` returns the value of the corresponding option. If no arguments are supplied, the names of all the available options and their current values are displayed.

## Orthogonal Collocation

Loadable Function: [r, A, B, q] = colloc (n, "left", "right")
Compute derivative and integral weight matrices for orthogonal collocation using the subroutines given in J. Villadsen and M. L. Michelsen, Solution of Differential Equation Models by Polynomial Approximation.