Coulomb#

cuest.bindings.cuestDFCoulombComputeWorkspaceQuery(
*,
handle: cuest.bindings.cuest.cuestHandle,
plan: cuest.bindings.cuest.cuestDFIntPlanHandle,
parameters: cuest.bindings.cuest.Parameters,
temporaryWorkspaceDescriptor: int,
densityMatrix: cuest.bindings.cuest.Pointer,
outCoulombMatrix: cuest.bindings.cuest.Pointer,
) → cuest.bindings.cuest.CuestStatus#

Query the temporary workspace required (in bytes) for a DF Coulomb matrix computation.

This function returns the workspace needed (host/device) for a single computation, based on the provided plan. Only sizes are computed; output and density buffers may be NULL.

Parameters#

handle[in]cuestHandle

cuEST handle. Must not be NULL.

plan[in]cuestDFIntPlanHandle

Density-fitted integral plan (opaque handle).

parameters[in]cuestDFCoulombComputeParameters_t

Parameters object. Must not be NULL.

temporaryWorkspaceDescriptor[out]WorkspaceDescriptor

Output descriptor for temporary workspace sizes. Must not be NULL. Modified in place.

densityMatrix[in]Pointer

Optional density matrix. May be NULL.

outCoulombMatrix[in]Pointer

Optional output Coulomb matrix. May be NULL.

Returns#

status[out]cuestStatus_t
cuest.bindings.cuestDFCoulombCompute(
*,
handle: cuest.bindings.cuest.cuestHandle,
plan: cuest.bindings.cuest.cuestDFIntPlanHandle,
parameters: cuest.bindings.cuest.Parameters,
temporaryWorkspace: int,
densityMatrix: cuest.bindings.cuest.Pointer,
outCoulombMatrix: cuest.bindings.cuest.Pointer,
) → cuest.bindings.cuest.CuestStatus#

Compute the AO Coulomb (J) matrix using density fitting (DF) with the supplied DF integral plan and density matrix.

This routine computes the Coulomb matrix (J) from a density matrix using an auxiliary basis and density-fitted integrals. The user must provide a preallocated density matrix (size: nao × nao) and a preallocated output buffer (size: nao × nao). All required temporary workspace must be allocated using the size returned by cuestDFCoulombComputeWorkspaceQuery().

Parameters#

handle[in]CuestHandle

cuEST handle. Must not be NULL.

plan[in]CuestDFIntPlanHandle

Density-fitted integral plan (opaque handle) constructed with cuestDFIntPlanCreate().

parameters[in]cuestDFCoulombComputeParameters_t

Parameters object. Must not be NULL.

temporaryWorkspace[in]Workspace

Temporary workspace buffer for this operation.

densityMatrix[in]Pointer

Input density matrix (size: nao × nao) on the GPU. Must not be NULL.

outCoulombMatrix[out]Pointer

Output buffer for computed Coulomb matrix (size: nao × nao) on the GPU. Must not be NULL. Elements of this array are overwritten by the calculation results.

Returns#

status[out]cuestStatus_t