tmap (version 1.2)

tm_facets: Small multiples

Description

Creates a tmap-element that specifies how small multiples are placed in a facet grid. Either the argument by should be specified, i.e. the name of a variable by which the data is grouped, or multiple variable names sould be provided with tm_fill, tm_lines, or tm_bubbles. In this function, the number of rows and columns can be specified, as well as whether the scales are free (i.e. independent of each other).

Usage

tm_facets(by = NULL, ncol = NULL, nrow = NULL, free.coords = FALSE,
  drop.shapes = free.coords, free.scales = is.null(by),
  free.scales.fill = free.scales, free.scales.bubble.size = free.scales,
  free.scales.bubble.col = free.scales, free.scales.text.size = free.scales,
  free.scales.text.col = free.scales, free.scales.line.col = free.scales,
  free.scales.line.lwd = free.scales, free.scales.raster = free.scales,
  inside.original.bbox = FALSE, scale.factor = 2)

Arguments

by

data variable name by which the data is split

ncol

number of columns of the small multiples grid

nrow

number of rows of the small multiples grid

free.coords

logical. If the by argument is specified, should each map has its own coordinate ranges?

drop.shapes

logical. If the by argument is specified, should all non-selected shapes be dropped?

free.scales

logical. Should all scales of the plotted data variables be free, i.e. independent of each other? Possible data variables are color from tm_fill, color and size from

free.scales.fill

logical. Should the color scale for the choropleth be free?

free.scales.bubble.size

logical. Should the bubble size scale for the bubble map be free?

free.scales.bubble.col

logical. Should the color scale for the bubble map be free?

free.scales.text.size

logical. Should the text size scale be free?

free.scales.text.col

logical. Should the text color scale be free?

free.scales.line.col

Should the line color scale be free?

free.scales.line.lwd

Should the line width scale be free?

free.scales.raster

Should the color scale for raster layers be free?

inside.original.bbox

If free.coords, should the bounding box of each small multiple be inside the original bounding box?

scale.factor

Number that determines how the elements (e.g. font sizes, bubble 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 o

Value

• tmap-element

See Also

../doc/tmap-nutshell.html{vignette("tmap-nutshell")}

Examples

data(World, Europe, NLD_muni, NLD_prov)

# Facets defined by constant values
tm_shape(World) +
    tm_fill(c("forestgreen", "goldenrod")) +
tm_format_World(title=c("A green world", "A dry world"), bg.color="lightskyblue2", 
    title.position=c("left", "bottom"))

# Facets defined by multiple variables
tm_shape(Europe) +
    tm_borders() +
    tm_fill(c("gdp_cap_est", "pop_est_dens"), style="kmeans", 
        title=c("GDP per capita", "Population density")) +
tm_format_Europe()

tm_shape(NLD_muni) +
    tm_fill(c("pop_0_14", "pop_15_24", "pop_25_44", "pop_45_64", "pop_65plus"),
        style="kmeans", 
        palette=list("Oranges", "Greens", "Blues", "Purples", "Greys"),
        title=c("Population 0 to 14", "Population 15 to 24", "Population 25 to 44",
            "Population 45 to 64", "Population 65 and older")) +
tm_shape(NLD_prov) +
    tm_borders() +
tm_format_NLD(frame = TRUE, asp=0)

# Facets defined by groupings
tm_shape(NLD_prov) +
    tm_borders() +
    tm_fill("gold2") +
    tm_facets(by="name") +
    tm_layout()

tm_shape(NLD_prov) +
    tm_fill("gold2") + tm_borders() +
    tm_facets(by="name", free.coords = TRUE, drop.shapes=TRUE) +
tm_layout()

tm_shape(NLD_muni) +
    tm_borders() +
    tm_facets(by="province") +
    tm_fill("population", style="kmeans", convert2density = TRUE) +
tm_shape(NLD_prov) +
    tm_borders(lwd=4) +
    tm_facets(by="name", free.coords=TRUE, drop.shapes=TRUE) +
tm_layout(legend.show = FALSE)