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tmap (version 1.2)

tm_lines: Draw spatial lines

Description

Creates a tmap-element that draw spatial lines.

Usage

tm_lines(col = NA, lwd = 1, lty = "solid", alpha = NA, scale = 1,
  lwd.legend = NULL, lwd.legend.labels = NULL, n = 5,
  style = ifelse(is.null(breaks), "pretty", "fixed"), breaks = NULL,
  palette = NULL, labels = NULL, auto.palette.mapping = TRUE,
  contrast = 1, max.categories = 12, colorNA = NA, textNA = "Missing",
  title.col = NA, title.lwd = NA, legend.col.show = TRUE,
  legend.lwd.show = TRUE, legend.format = list(),
  legend.col.is.portrait = TRUE, legend.lwd.is.portrait = FALSE,
  legend.hist = FALSE, legend.hist.title = NA, legend.col.z = NA,
  legend.lwd.z = NA, legend.hist.z = NA, id = NA)

Arguments

col
color of the lines. Either a color value or a data variable name. If multiple values are specified, small multiples are drawn (see details).
lwd
line width. If multiple values are specified, small multiples are drawn (see details).
lty
line type.
alpha
transparency number between 0 (totally transparent) and 1 (not transparent). By default, the alpha value of the col is used (normally 1).
scale
line width multiplier number.
lwd.legend
vector of line widths that are shown in the legend. By default, this is determined automatically.
lwd.legend.labels
vector of labels for that correspond to lwd.legend.
n
preferred number of color scale classes. Only applicable when lwd is the name of a numeric variable.
style
method to process the color scale when col is a numeric variable. Discrete options are "cat", "fixed", "sd", "equal", "pretty", "quantile", "kmeans", <
breaks
in case style=="fixed", breaks should be specified
palette
color palette (see RColorBrewer::display.brewer.all) for the lines. Only when col is set to a variable. The default palette is taken from tm_layout's argument aes.palette
labels
labels of the classes
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 respect
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 t
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, then levels are combined.
colorNA
color used for missing values
textNA
text used for missing values. Use NA to omit text for missing values in the legend
title.col
title of the legend element regarding the line colors
title.lwd
title of the legend element regarding the line widths
legend.col.show
logical that determines whether the legend for the line colors is shown
legend.lwd.show
logical that determines whether the legend for the line widths is shown
legend.format
list of formatting options for the legend numbers. Only applicable if labels is undefined. Parameters are: [object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
legend.col.is.portrait
logical that determines whether the legend element regarding the line colors is in portrait mode (TRUE) or landscape (FALSE)
legend.lwd.is.portrait
logical that determines whether the legend element regarding the line widths is in portrait mode (TRUE) or landscape (FALSE)
legend.hist
logical that determines whether a histogram is shown regarding the line colors
legend.hist.title
title for the histogram. By default, one title is used for both the histogram and the normal legend for line colors.
legend.col.z
index value that determines the position of the legend element regarding the line colors 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.lwd.z
index value that determines the position of the legend element regarding the line widths. (See legend.col.z)
legend.hist.z
index value that determines the position of the legend element regarding the histogram. (See legend.col.z)
id
name of the data variable that specifies the indices of the lines. Only used for SVG output (see itmap).

Value

Details

Small multiples can be drawn in two ways: either by specifying the by argument in tm_facets, or by defining multiple variables in the aesthetic arguments. The aesthetic arguments of tm_lines are col and lwd. In the latter case, the arguments, except for the ones starting with legend., can be specified for small multiples as follows. If the argument normally only takes a single value, such as n, then a vector of those values can be specified, one for each small multiple. If the argument normally can take a vector, such as palette, then a list of those vectors (or values) can be specified, one for each small multiple.

See Also

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

Examples

Run this code
data(World, Europe, rivers)

qtm(rivers, line.col = "navy")

tm_shape(Europe) +
  tm_fill("MAP_COLORS", palette = "Pastel2") +
tm_shape(rivers) +
  tm_lines(col="black", lwd="scalerank", scale=2, legend.lwd.show = FALSE) +
tm_layout("Rivers of Europe") +
	tm_style_cobalt()

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