cheb_quad2 – chebpak

public function cheb_quad2(tag, x0, x1, y0, y1, nx, ny, x, y, f, rwrk) result(valint)

This subroutine evaluates an integral using Gauss-Chebyshev (CGL/CGR/CG) quadrature for two variables.

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)		::	x0	Domain bounds [x0, x1]x[y0, y1] along x and y directions.
real(kind=rp),	intent(in)		::	x1	Domain bounds [x0, x1]x[y0, y1] along x and y directions.
real(kind=rp),	intent(in)		::	y0	Domain bounds [x0, x1]x[y0, y1] along x and y directions.
real(kind=rp),	intent(in)		::	y1	Domain bounds [x0, x1]x[y0, y1] along x and y directions.
integer,	intent(in)		::	nx	Number of nodes along x and y directions are (nx+1) and (ny+1)
integer,	intent(in)		::	ny	Number of nodes along x and y directions are (nx+1) and (ny+1)
real(kind=rp),	intent(in),	dimension(:)	::	x	(nx+1,). Nodal coordinates along x direction in [-1, 1]
real(kind=rp),	intent(in),	dimension(:)	::	y	(ny+1,). Nodal coordinates along y direction in [-1, 1]
real(kind=rp),	intent(in),	dimension(:)	::	f	((nx+1)*(ny+1),). Value of the function at the nodes
real(kind=rp),	intent(inout),	dimension(:)	::	rwrk	Workspace array of size at least (ny+1)