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Specify facets. tm_facets() is the core function, but recommended is to use tm_facets_wrap(), tm_facets_stack() or tm_facets_grid(). The former two specify facets for one grouping variable (so one faceting dimension). The difference is that wrap may place facets in multiple rows and columns whereas tm_facets_stack() stacks the facets either horizontally or vertically. tm_facets_grid() supports up to three faceting dimensions.

Usage

tm_facets(
  by = NULL,
  rows = NULL,
  columns = NULL,
  pages = NULL,
  as.layers = FALSE,
  nrows = NA,
  ncols = NA,
  byrow = TRUE,
  orientation = NA,
  free.coords = NA,
  drop.units = TRUE,
  drop.empty.facets = TRUE,
  drop.NA.facets = FALSE,
  sync = TRUE,
  showNA = NA,
  textNA = "Mssing",
  scale.factor = 2,
  type = NA,
  along = NULL,
  free.scales = NULL
)

tm_facets_grid(rows = NULL, columns = NULL, pages = NULL, ...)

tm_facets_wrap(by = "VARS__", nrows = NA, ncols = NA, byrow = TRUE, ...)

tm_facets_pagewise(by = "VARS__", nrows = 1, ncols = 1, byrow = TRUE, ...)

tm_facets_stack(by = "VARS__", orientation = NA, ...)

tm_facets_hstack(by = "VARS__", ...)

tm_facets_vstack(by = "VARS__", ...)

tm_facets_flip()

Arguments

by

Group by variable (only for a facet wrap or facet stack)

rows

Variable that specifies the rows (only for a facet grid)

columns

Variable that specifies the columns (only for a facet grid)

pages

Variable that specifies the pages (only for a facet grid)

as.layers

show facets as layers?

nrows

Number of rows

ncols

Number of columns

byrow

Should facets be wrapped by row?

orientation

For facet stack: horizontal or vertical?

free.coords

Logical. If the by argument is specified, should each map has its own coordinate ranges? By default TRUE, unless facets are shown in as different layers (as.layers = TRUE)

drop.units

Logical. If the by argument is specified, should non-selected spatial units be dropped? If FALSE, they are plotted where mapped aesthetics are regarded as missing values. Not applicable for raster shapes. By default TRUE.

drop.empty.facets

Logical. If the by argument is specified, should empty facets be dropped? Empty facets occur when the by-variable contains unused levels. When TRUE and two by-variables are specified, empty rows and columns are dropped.

drop.NA.facets

Logical. If the by argument is specified, and all data values for specific facets are missing, should these facets be dropped? FALSE by default.

sync

Logical. Should the navigation in view mode (zooming and panning) be synchronized? By default TRUE if the facets have the same bounding box. This is generally the case when rasters are plotted, or when free.coords is FALSE.

showNA

If the by argument is specified, should missing values of the by-variable be shown in a facet? If two by-variables are specified, should missing values be shown in an additional row and column? If NA, missing values only are shown if they exist. Similar to the useNA argument of table(), where TRUE, FALSE, and NA correspond to "always", "no", and "ifany" respectively.

textNA

Text used for facets of missing values.

scale.factor

Number that determines how the elements (e.g. font sizes, symbol sizes, line widths) of the small multiples are scaled in relation to the scaling factor of the shapes. The elements are scaled to the scale.factorth root of the scaling factor of the shapes. So, for scale.factor=1, they are scaled proportional to the scaling of the shapes. Since elements, especially text, are often too small to read, a higher value is recommended. By default, scale.factor=2.

type

"grid", "wrap" or "stack"

along

deprecated Please use tm_facets_page()

free.scales

deprecated. Please use the .free arguments in the layer functions, e.g. fill.free in tm_polygons.

...

passed on to tm_facets()