Dimensionality

This section describes the handling of dimensionality in WarpX.

Build Options

Dimensions	CMake Option
3D3V	`WarpX_DIMS=3` (default)
2D3V	`WarpX_DIMS=2`
1D3V	`WarpX_DIMS=1`
RZ3V	`WarpX_DIMS=RZ`
RCYLINDER3V	`WarpX_DIMS=RCYLINDER`
RSPHERE3V	`WarpX_DIMS=RSPHERE`

Note that one can build multiple WarpX dimensions at once via -DWarpX_DIMS="1;2;3;RZ;RCYLINDER;RSPHERE".

See building from source for further details.

Defines

Depending on the build variant of WarpX, the following preprocessor macros will be set:

Macro	3D3V	2D3V	1D3V	RZ3V	RCYLINDER3V	RSPHERE3V
`AMREX_SPACEDIM`	`3`	`2`	`1`	`2`	`1`	`1`
`WARPX_DIM_3D`	defined	undefined	undefined	undefined	undefined	undefined
`WARPX_DIM_1D_Z`	undefined	undefined	defined	undefined	undefined	undefined
`WARPX_DIM_XZ`	undefined	defined	undefined	undefined	undefined	undefined
`WARPX_DIM_RZ`	undefined	undefined	undefined	defined	undefined	undefined
`WARPX_DIM_RCYLINDER`	undefined	undefined	undefined	undefined	defined	undefined
`WARPX_DIM_RSPHERE`	undefined	undefined	undefined	undefined	undefined	defined
`WARPX_ZINDEX`	`2`	`1`	`0`	`1`	undefined	undefined

At the same time, the following conventions will apply:

Convention	3D3V	2D3V	1D3V	RZ3V	RCYLINDER3V	RSPHERE3V
Fields
AMReX Box dimensions	`3`	`2`	`1`	`2`	`1`	`1`
WarpX axis labels	`x, y, z`	`x, z`	`z`	`x, z`	`r`	`r`
Particles
AMReX `.pos()`	`0, 1, 2`	`0, 1`	`0`	`0, 1`	`0`	`0`
WarpX position names	`x, y, z`	`x, z`	`z`	`r, z`	`r`	`r`
extra SoA attribute				`theta`	`theta`	`theta, phi`

Please see the following sections for particle SoA details.

Conventions

In 2D3V, we assume that the position of a particle in y is equal to 0. In 1D3V, we assume that the position of a particle in x and y is equal to 0.