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Diffstat (limited to 'Docs/source/running_cpp/parameters.rst')
| -rw-r--r-- | Docs/source/running_cpp/parameters.rst | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/Docs/source/running_cpp/parameters.rst b/Docs/source/running_cpp/parameters.rst index 393c19980..13088f69c 100644 --- a/Docs/source/running_cpp/parameters.rst +++ b/Docs/source/running_cpp/parameters.rst @@ -112,7 +112,7 @@ user-defined constant and ``x`` and ``y`` are variables. The names are case sens define functions by intervals. User-defined constants can be used in parsed functions only (i.e., ``density_function(x,y,z)`` and ``field_function(X,Y,t)``, see below). User-defined constants can contain only letter, numbers and character _. -The name of each constant has to begin with a letter. The following names are used +The name of each constant has to begin with a letter. The following names are used by WarpX, and cannot be used as user-defined constants: `x`, `y`, `z`, `X`, `Y`, `t`. For example, parameters ``a0`` and ``z_plateau`` can be specified with: @@ -436,8 +436,14 @@ Numerics and algorithms * ``psatd.nox``, ``psatd.noy``, ``pstad.noz`` (`integer`) optional (default `16` for all) The order of accuracy of the spatial derivatives, when using the code compiled with a PSATD solver. +* ``psatd.hybrid_mpi_decomposition`` (`0` or `1`; default: 0) + Whether to use a different MPI decomposition for the particle-grid operations + (deposition and gather) and for the PSATD solver. If `1`, the FFT will + be performed over MPI groups. + * ``psatd.ngroups_fft`` (`integer`) - The number of MPI groups that are created for the FFT, when using the code compiled with a PSATD solver. + The number of MPI groups that are created for the FFT, when using the code compiled with a PSATD solver + (and only if `hybrid_mpi_decomposition` is `1`). The FFTs are global within one MPI group and use guard cell exchanges in between MPI groups. (If ``ngroups_fft`` is larger than the number of MPI ranks used, than the actual number of MPI ranks is used instead.) |