tmap (version 1.10)

tm_text: Add text labels

Description

Creates a tmap-element that adds text labels.

Usage

tm_text(text, size = 1, col = NA, root = 3, size.lim = NA,
  sizes.legend = NULL, sizes.legend.labels = NULL,
  sizes.legend.text = "Abc", n = 5, style = ifelse(is.null(breaks),
  "pretty", "fixed"), breaks = NULL, interval.closure = "left",
  palette = NULL, labels = NULL, labels.text = NA,
  auto.palette.mapping = TRUE, contrast = NA, max.categories = 12,
  colorNA = NA, textNA = "Missing", showNA = NA, fontface = NA,
  fontfamily = NA, alpha = NA, case = NA, shadow = FALSE,
  bg.color = NA, bg.alpha = NA, size.lowerbound = 0.4,
  print.tiny = FALSE, scale = 1, auto.placement = FALSE,
  remove.overlap = FALSE, along.lines = FALSE, overwrite.lines = FALSE,
  just = c("center", "center"), xmod = 0, ymod = 0, title.size = NA,
  title.col = NA, legend.size.show = TRUE, legend.col.show = TRUE,
  legend.format = list(), legend.size.is.portrait = FALSE,
  legend.col.is.portrait = TRUE, legend.hist = FALSE,
  legend.hist.title = NA, legend.size.z = NA, legend.col.z = NA,
  legend.hist.z = NA)

Arguments

text

name of the variable in the shape object that contains the text labels

size

relative size of the text labels (see note). Eiter one number, a name of a numeric variable in the shape data that is used to scale the sizes proportionally, or the value "AREA", where the text size is proportional to the area size of the polygons.

col

color of the text labels. Either a color value or a data variable name. If multiple values are specified, small multiples are drawn (see details).

root

root number to which the font sizes are scaled. Only applicable if size is a variable name or "AREA". If root=2, the square root is taken, if root=3, the cube root etc.

size.lim

vector of two limit values of the size variable. Only text labels are drawn whose value is greater than or equal to the first value. Text labels whose values exceed the second value are drawn at the size of the second value. Only applicable when size is the name of a numeric variable of shp. See also size.lowerbound which is a threshold of the relative font size.

sizes.legend

vector of text sizes that are shown in the legend. By default, this is determined automatically.

sizes.legend.labels

vector of labels for that correspond to sizes.legend.

sizes.legend.text

vector of example text to show in the legend next to sizes.legend.labels. By default "Abc". When NA, examples from the data variable whose sizes are close to the sizes.legend are taken and "NA" for classes where no match is found.

n

preferred number of color scale classes. Only applicable when col is a numeric variable name.

style

method to process the color scale when col is a numeric variable. Discrete options are "cat", "fixed", "sd", "equal", "pretty", "quantile", "kmeans", "hclust", "bclust", "fisher", and "jenks". A numeric variable is processed as a categorial variable when using "cat", i.e. each unique value will correspond to a distinct category. For the other discrete options, see the details in classIntervals. Continuous options are "cont" and "order". The former maps the values of col to a smooth gradient, whereas the latter maps the order of values of col to a smooth gradient. They are the continuous variants of respectively the discrete methods "equal" and quantile".

breaks

in case style=="fixed", breaks should be specified. The breaks argument can also be used when style="cont". In that case, the breaks are mapped evenly to the sequential or divering color palette.

interval.closure

value that determines whether where the intervals are closed: "left" or "right". Only applicable if col is a numerc variable.

palette

a palette name or a vector of colors. See tmaptools::palette_explorer() for the named palettes. Use a "-" as prefix to reverse the palette. The default palette is taken from tm_layout's argument aes.palette, which typically depends on the style. The type of palette from aes.palette is automatically determined, but can be overwritten: use "seq" for sequential, "div" for diverging, and "cat" for categorical.

labels

labels of the color classes, applicable if col is a data variable name

labels.text

Example text to show in the legend next to the labels. When NA (default), examples from the data variable are taken and "NA" for classes where they don't exist.

auto.palette.mapping

When diverging colour palettes are used (i.e. "RdBu") this method automatically maps colors to values such that the middle colors (mostly white or yellow) are assigned to values of 0, and the two sides of the color palette are assigned to negative respectively positive values. When categorical color palettes are used, this method stretches the palette if there are more levels than colors.

contrast

vector of two numbers that determine the range that is used for sequential and diverging palettes (applicable when auto.palette.mapping=TRUE). Both numbers should be between 0 and 1. The first number determines where the palette begins, and the second number where it ends. For sequential palettes, 0 means the brightest color, and 1 the darkest color. For diverging palettes, 0 means the middle color, and 1 both extremes. If only one number is provided, this number is interpreted as the endpoint (with 0 taken as the start).

max.categories

in case col is the name of a categorical variable, this value determines how many categories (levels) it can have maximally. If the number of levels is higher than max.categories and auto.palette.mapping is FALSE, then levels are combined.

colorNA

colour for missing values. Use NULL for transparency.

textNA

text used for missing values.

showNA

logical that determines whether missing values are named in the legend. By default (NA), this depends on the presence of missing values.

fontface

font face of the text labels. By default, determined by the fontface argument of tm_layout.

fontfamily

font family of the text labels. By default, determined by the fontfamily argument of tm_layout.

alpha

transparency number between 0 (totally transparent) and 1 (not transparent). By default, the alpha value of the fontcolor is used (normally 1).

case

case of the font. Use "upper" to generate upper-case text, "lower" to generate lower-case text, and NA to leave the text as is.

shadow

logical that determines whether a shadow is depicted behind the text. The color of the shadow is either white or yellow, depending of the fontcolor.

bg.color

background color of the text labels. By default, bg.color=NA, so no background is drawn.

bg.alpha

number between 0 and 1 that specifies the transparancy of the text background (0 is totally transparent, 1 is solid background).

size.lowerbound

lowerbound for size. Only applicable when size is not a constant. If print.tiny is TRUE, then all text labels which relative text is smaller than size.lowerbound are depicted at relative size size.lowerbound. If print.tiny is FALSE, then text labels are only depicted if their relative sizes are at least size.lowerbound (in other words, tiny labels are omitted).

print.tiny

boolean, see size.lowerbound

scale

text size multiplier, useful in case size is variable or "AREA".

auto.placement

logical (or numeric) that determines whether the labels are placed automatically. If TRUE, the labels are placed next to the coordinate points with as little overlap as possible using the simulated annealing algorithm. Therefore, it is recommended for labeling spatial dots or symbols. If a numeric value is provided, this value acts as a parameter that specifies the distance between the coordinate points and the text labels in terms of text line heights.

remove.overlap

logical that determines whether the overlapping labels are removed

along.lines

logical that determines whether labels are rotated along the spatial lines. Only applicabel if a spatial lines shape is used.

overwrite.lines

logical that determines whether the part of the lines below the text labels is removed. Only applicabel if a spatial lines shape is used.

just

justification of the text 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 alignment and 1 right alignment.

xmod

horizontal position modification of the text (relatively): 0 means no modification, and 1 corresponds to the height of one line of text. Either a single number for all polygons, or a numeric variable in the shape data specifying a number for each polygon. Together with ymod, it determines position modification of the text labels. In most coordinate systems (projections), the origin is located at the bottom left, so negative xmod move the text to the left, and negative ymod values to the bottom.

ymod

vertical position modification. See xmod.

title.size

title of the legend element regarding the text sizes

title.col

title of the legend element regarding the text colors

legend.size.show

logical that determines whether the legend for the text sizes is shown

legend.col.show

logical that determines whether the legend for the text colors is shown

legend.format

list of formatting options for the legend numbers. Only applicable if labels is undefined. Parameters are:

fun

Function to specify the labels. It should take a numeric vector, and should return a character vector of the same size. By default it is not specified. If specified, the list items scientific, format, and digits (see below) are not used.

scientific

Should the labels be formatted scientically? If so, square brackets are used, and the format of the numbers is "g". Otherwise, format="f", and text.separator, text.less.than, and text.or.more are used. Also, the numbers are automatically rounded to millions or billions if applicable.

format

By default, "f", i.e. the standard notation xxx.xxx, is used. If scientific=TRUE then "g", which means that numbers are formatted scientically, i.e. n.dddE+nn if needed to save space.

digits

Number of digits after the decimal point if format="f", and the number of significant digits otherwise.

text.separator

Character string to use to separate numbers in the legend (default: "to").

text.less.than

Character string to use to translate "Less than" (which is the default).

text.or.more

Character string to use to translate "or more" (which is the default).

...

Other arguments passed on to formatC

legend.size.is.portrait

logical that determines whether the legend element regarding the text sizes is in portrait mode (TRUE) or landscape (FALSE)

legend.col.is.portrait

logical that determines whether the legend element regarding the text colors is in portrait mode (TRUE) or landscape (FALSE)

legend.hist

logical that determines whether a histogram is shown regarding the text colors

legend.hist.title

title for the histogram. By default, one title is used for both the histogram and the normal legend for text colors.

legend.size.z

index value that determines the position of the legend element regarding the text sizes with respect to other legend elements. The legend elements are stacked according to their z values. The legend element with the lowest z value is placed on top.

legend.col.z

index value that determines the position of the legend element regarding the text colors. (See legend.size.z)

legend.hist.z

index value that determines the position of the histogram legend element. (See legend.size.z)

Value

tmap-element

See Also

vignette("tmap-nutshell")

Examples

Run this code
# NOT RUN {
current.mode <- tmap_mode("plot")

data(World, Europe, metro)

tm_shape(World) +
    tm_text("name", size="AREA")

tm_shape(Europe) +
    tm_polygons() +
    tm_text("iso_a3", size="AREA", col = "grey20", root=4, shadow = TRUE, scale=2,
        size.lowerbound = .1) +
tm_shape(Europe) +
    tm_text("name", size="AREA", root=4, scale=1,
        ymod=-1 * tmaptools::approx_areas(Europe, target = "norm")^(1/4))

tm_shape(Europe) +
	tm_polygons() +
tm_shape(metro) +
	tm_bubbles("pop2010", size.lim = c(0, 15e6),
			   title.size = "European metropolitan areas") +
tm_shape(metro[metro$pop2010>=2e6, ]) +
	tm_text("name", auto.placement = TRUE) +
	tm_format_Europe()

tm_shape(World) +
	tm_text("name", size="pop_est", col="continent", palette="Dark2", 
			title.size = "Population", title.col="Continent") +
	tm_legend(outside = TRUE)

# restore current mode
tmap_mode(current.mode)
# }

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