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Legend charts

Source: R/tm_chart.R
tm_chart.Rd

Legend charts are small charts that are added to the map, usually in addition to legends.

Usage

tm_chart_histogram(
  breaks,
  plot.axis.x,
  plot.axis.y,
  extra.ggplot2,
  position,
  group_id,
  width,
  height,
  stack,
  z,
  ...
)

tm_chart_bar(
  plot.axis.x,
  plot.axis.y,
  extra.ggplot2,
  position,
  group_id,
  width,
  height,
  stack,
  z,
  ...
)

tm_chart_donut(position, group_id, width, height, stack, z, ...)

tm_chart_violin(position, group_id, width, height, stack, z, ...)

tm_chart_box(position, group_id, width, height, stack, z, ...)

tm_chart_none()

tm_chart_heatmap(position, group_id, width, height, stack, z, ...)

Arguments

breaks

The breaks of the bins (for histograms)

plot.axis.x, plot.axis.y

Should the x axis and y axis be plot?

extra.ggplot2

Extra ggplot2 code

position

The position specification of the component: an object created with tm_pos_in() or tm_pos_out(). Or, as a shortcut, a vector of two values, specifying the x and y coordinates. The first is "left", "center" or "right" (or upper case, meaning tighter to the map frame), the second "top", "center" or "bottom". Numeric values are also supported, where 0, 0 means left bottom and 1, 1 right top. See also vignette about positioning. In case multiple components should be combined (stacked), use group_id and specify component in tm_comp_group().

group_id

Component group id name. All components (e.g. legends, titles, etc) with the same group_id will be grouped. The specifications of how they are placed (e.g. stacking, margins etc.) are determined in tm_comp_group() where its argument id should correspond to group_id.

width, height

width and height of the component.

stack

stack with other map components, either "vertical" or "horizontal".

z

z index, e.g. the place of the component relative to the other componets

...

passed on to tm_title()

Details

Note that these charts are different from charts drawn inside the map. Those are called glyphs (to be implemented).

See also

Vignette about charts

Examples

tm_shape(World) +
  tm_polygons("HPI",
    fill.scale = tm_scale_intervals(),
    fill.chart = tm_chart_histogram())