[gf<cartesian_product<X,Y,…>>] Multiple variables

Domain & mesh

The domain is a cartesian product of domains.

The mesh is a cartesian product of the corresponding meshes.

Subscript operator

In addition to the general subscript functionality of the Green function, the cartesian product provides the functionality to write expressions such as

g[x1, x2, ..]

where the xi are mesh points of the respective mesh-component of the cartesian product.

Clef expressions

The subscript operator in clef expression assignment has also been extended to allow for assignments of the kind

g[_x1, _x2, ..] << g1[y1, _x1] * g2[_x2, y2] * ...

where the _xi are clef placeholders, and yi denote mesh points of the respective meshes of the gi.

Singularity

None.

Interpolation method

A multidimensional linear interpolation is automatically built from the linear interpolation of the domains.

Data storage

Like single variables gf, the first index of the array is a flattening of the indices of the composite mesh.

HDF5 storage convention

For convenience, in hdf5 files, the arrays has higher dimension, so that the first indices are not flatten. EXPLAIN.

Functional techniques

See:

Examples