Line Integrals

The operators BINTEGRAL and LINE_INTEGRAL are synonymous, and perform line integrations. 

The integral is always taken with respect to distance along the line or curve.

At present, line integrals are only meaningful in 2D problems.  General 3D line integrals are not yet implemented.

In 2D Cartesian geometry, LINE_INTEGRAL is the same as SURF_INTEGRAL. 

In 2D cylindrical geometry, SURF_INTEGRAL will contain the 2*pi*r weighting, while LINE_INTEGRAL will not.

BINTEGRAL ( integrand, named_boundary )

LINE_INTEGRAL ( integrand, named_boundary )

The boundary specification may be omitted, in which case the entire outer boundary is implied.

Line integrals may be further qualified by specifying the region in which the evaluation is to be made:

LINE_INTEGRAL ( integrand, named_boundary, named_region )

named_region must be one of the regions bounded by the selected boundary.