MultiFab arithmetic (saxpy, lincomb, norm_inf, dot) over VALID cells. More...

#include <pops/core/foundation/types.hpp>
#include <pops/mesh/index/box2d.hpp>
#include <pops/mesh/storage/fab2d.hpp>
#include <pops/mesh/execution/for_each.hpp>
#include <pops/mesh/storage/multifab.hpp>
#include <pops/parallel/comm.hpp>
#include <algorithm>
#include <limits>

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Classes
struct	pops::detail::SaxpyKernel

struct	pops::detail::LincombKernel

struct	pops::detail::NormInfKernel

struct	pops::detail::DotKernel

struct	pops::detail::SumKernel

struct	pops::detail::MaxKernel

struct	pops::detail::MinKernel

Namespaces
namespace	pops

namespace	pops::detail

Functions
void	pops::saxpy (MultiFab &y, Real a, const MultiFab &x)
	y <- y + a x over ALL components of the valid cells. Identical layouts required.

Real	pops::norm_inf (const MultiFab &mf, int comp=0)
	Infinity norm max \|f(.,.,comp)\| over the valid cells (LOCAL, without MPI all_reduce).

void	pops::lincomb (MultiFab &z, Real a, const MultiFab &x, Real b, const MultiFab &y)
	z <- a x + b y over ALL components of the valid cells. Identical layouts; aliasing safe.

Real	pops::dot (const MultiFab &x, const MultiFab &y, int comp=0)
	Dot product Sum_cells x.y over component comp, reduced over ALL ranks (all_reduce).

Real	pops::dot_all (const MultiFab &x, const MultiFab &y)
	FULL-component dot Sum_{cells, c} x(.,.,c) * y(.,.,c) over ALL components, reduced over ALL ranks (all_reduce).

Real	pops::reduce_sum (const MultiFab &mf, int comp=0)
	Sum Sum_cells f(.,.,comp) over component comp, reduced over ALL ranks (all_reduce_sum) – the compiled-Program P.sum / P.sum_component reduction.

Real	pops::reduce_max (const MultiFab &mf, int comp=0)
	Signed maximum max_cells f(.,.,comp) over component comp, reduced over ALL ranks (all_reduce_max) – the compiled-Program P.max reduction (SIGNED, not the magnitude – use norm_inf for max\|f\|).

Real	pops::reduce_min (const MultiFab &mf, int comp=0)
	Signed minimum min_cells f(.,.,comp) over component comp, reduced over ALL ranks (all_reduce_min) – the compiled-Program P.min reduction.

Detailed Description

MultiFab arithmetic (saxpy, lincomb, norm_inf, dot) over VALID cells.

Building blocks for integrator stages and Krylov solvers. Assumes IDENTICAL layouts (same BoxArray, same DistributionMapping). Pointwise operations -> ALIASING is safe (x or y == z allowed). norm_inf / dot go through the reducer seam (true Kokkos reduction). dot performs a COLLECTIVE all_reduce: it MUST be called on EVERY rank (including a rank with no box) under MPI, otherwise deadlock. FP NOTE: dot/sum are re-associated per tile (Kokkos::Sum, deterministic/idempotent but not bit-identical to a lexicographic sum, for all Kokkos spaces); norm_inf is exact everywhere. The kernels are device-clean NAMED FUNCTORS (nvcc cross-TU).

include/pops/mesh/storage/mf_arith.hpp File Reference¶

Classes

Namespaces

Functions

Detailed Description