cheb_quad – chebpak

public function cheb_quad(tag, a, b, n, x, f) result(valint)

This subroutine evaluates an integral using Gauss-Chebyshev (CGL/CGR/CG) quadrature for a single variable.

Type	Intent	Attributes		Name
character(len=*),	intent(in)		::	tag	{`'CGL'`, `'CG'`, `'CGR'`} Type of nodes, where `'CGL'`: Chebyshev-Gauss-Lobatto, `'CG'`: Chebyshev-Gauss, and `'CGR'`: Chebyshev-Gauss-Radau.
real(kind=rp),	intent(in)		::	a	Domain bounds [a, b]
real(kind=rp),	intent(in)		::	b	Domain bounds [a, b]
integer,	intent(in)		::	n	Number of nodes is n+1
real(kind=rp),	intent(in),	dimension(0:n)	::	x	Nodal coordinates in [-1, 1]
real(kind=rp),	intent(in),	dimension(0:n)	::	f	Value of the function at the nodes