tmap (version 1.6)

tm_compass: Map compass

Description

Creates a map compass.

Usage

tm_compass(north = 0, type = NA, fontsize = 0.8, size = NA, show.labels = 1, cardinal.directions = c("N", "E", "S", "W"), text.color = NA, color.dark = NA, color.light = NA, lwd = 1, position = NA, just = NA)

Arguments

north

north direction in degrees: 0 means up, 90 right, etc.

type

compass type, one of: "arrow", "4star", "8star", "radar", "rose". The default is controlled by tm_layout (which uses "arrow" for the default style)

fontsize

relative font size

size

size of the compass in number of text lines. The default values depend on the type: for "arrow" it is 2, for "4star" and "8star" it is 4, and for "radar" and "rose" it is 6.

show.labels

number that specifies which labels are shown: 0 means no labels, 1 (default) means only north, 2 means all four cardinal directions, and 3 means the four cardinal directions and the four intercardinal directions (e.g. north-east).

cardinal.directions

labels that are used for the cardinal directions north, east, south, and west.

text.color

color of the text. By default equal to the argument attr.color of tm_layout.

color.dark

color of the dark parts of the compass, typically (and by default) black.

color.light

color of the light parts of the compass, typically (and by default) white.

lwd

line width of the compass

position

position of the compass. Vector of two values, specifing the x and y coordinates. Either this vector contains "left", "LEFT", "center", "right", or "RIGHT" for the first value and "top", "TOP", "center", "bottom", or "BOTTOM" for the second value, or this vector contains two numeric values between 0 and 1 that specifies the x and y value of the left bottom corner of the compass. The uppercase values correspond to the position without margins (so tighter to the frame). The default value is controlled by the argument "attr.position" of tm_layout.

just

Justification of the attribute relative to the point coordinates. The first value specifies horizontal and the second value vertical justification. Possible values are: "left" , "right", "center", "bottom", and "top". Numeric values of 0 specify left/bottom alignment and 1 right/top alignment. This option is only used, if position is specified by numeric coordinates. The default value is controlled by the argument "attr.just" of tm_layout.

Examples

current.mode <- tmap_mode("plot")

data(NLD_muni)

qtm(NLD_muni, theme = "NLD") + tm_compass()
qtm(NLD_muni, theme = "NLD") + tm_compass(type="8star")
qtm(NLD_muni, theme = "NLD") + tm_compass(type="8star")
qtm(NLD_muni, theme = "NLD") + tm_compass(type="radar", position=c("left", "top"), show.labels = 3)

# restore current mode
tmap_mode(current.mode)