5.10. Primitive operators and wrappers

mirgecom.operators provides helper functions for composing DG operators.

mirgecom.operators.grad_operator(dcoll, dd_vol, dd_allfaces, u, flux)

Compute a DG gradient for the input u with flux given by flux.

Parameters:

• dcoll (grudge.discretization.DiscretizationCollection) – the discretization collection to use

• dd_vol (grudge.dof_desc.DOFDesc) – the degree-of-freedom tag associated with the volume discretization. This determines the type of quadrature to be used.

• dd_allfaces (grudge.dof_desc.DOFDesc) – the degree-of-freedom tag associated with the surface discretization. This determines the type of quadrature to be used.

• u (meshmode.dof_array.DOFArray or numpy.ndarray) – the function (or container of functions) for which gradient is to be calculated

• flux (numpy.ndarray) – the boundary flux across the faces of the element for each component of u

Returns:

the dg gradient operator applied to u

Return type:

meshmode.dof_array.DOFArray or numpy.ndarray

mirgecom.operators.div_operator(dcoll, dd_vol, dd_allfaces, v, flux)

Compute DG divergence of vector-valued func v with flux given by flux.

Parameters:

• dcoll (grudge.discretization.DiscretizationCollection) – the discretization collection to use

• dd_vol (grudge.dof_desc.DOFDesc) – the degree-of-freedom tag associated with the volume discretization. This determines the type of quadrature to be used.

• dd_allfaces (grudge.dof_desc.DOFDesc) – the degree-of-freedom tag associated with the surface discretization. This determines the type of quadrature to be used.

• v (numpy.ndarray) – obj array of DOFArray (or container of such) representing the vector-valued functions for which divergence is to be calculated

• flux (numpy.ndarray) – the boundary flux for each function in v

Returns:

the dg divergence operator applied to vector-valued function(s) v.

Return type:

meshmode.dof_array.DOFArray or numpy.ndarray