ggpolar: Nicely formatted polar ggplot

In EarthSystemDiagnostics/ecustools: A miscellaneous collection of R functions for working with time-series and paleo data.

Description

Produce nicely formatted maps of the Arctic or Antarctic in polar projection. Also works for longitudinal segments, e.g. just Greenland.

Usage

ggpolar(
  pole = c("N", "S"),
  max.lat,
  min.lat,
  max.lon = 180,
  min.lon = -180,
  longitude.spacing = 60,
  land.fill.colour = "Grey",
  country.outline.colour = "Black",
  n.lat.labels = 4,
  nearest.x.degrees = 5,
  f.long.label.ticks = 20,
  f.long.label.pos = 7,
  lat.ax.vals = NULL,
  long.ax.vals = NULL,
  rotate = FALSE,
  size.outer = 1,
  plt.lat.axes = TRUE,
  plt.lat.labels = plt.lat.axes,
  plt.lon.axes = TRUE,
  plt.lon.labels = plt.lon.axes,
  rotate.long.labels = TRUE,
  lat.ax.labs.pos = NULL,
  ax.labs.size = 4,
  clip = "on",
  data.layer = NULL
)

Arguments

pole	character; which pole: "N" or "S"?
max.lat	maximum latitude.
min.lat	minimum latitude.
max.lon	maximum longitude.
min.lon	minimum longitude.
longitude.spacing	interval between longitude axis tick marks.
land.fill.colour	colour to shade the land.
country.outline.colour	colour for political boundaries (default "Black"); set to the same as land.fill.colour to hide them.
n.lat.labels	approximate number of latitude tickmarks.
nearest.x.degrees	round latitude tickmarks to how many degrees?
f.long.label.ticks	fraction of the plotted latitude axis range by which the longitude ticksmarks extend behind the outer latitude axis, i.e. the minimum (maximum) latitude for north (south) polar plots.
f.long.label.pos	fraction of the plotted latitude axis range by which the longitude labels are offset from the outer latitude axis.
lat.ax.vals	manually set the latitude axis values where to plot latitude labels and lines. This overrides the automatic setting by n.lat.labels and x.nearest.degress, while the default NULL means to use the automatic setting.
long.ax.vals	manually set the longitude axis values where to plot longitude labels and lines. This overrides the automatic setting by longitude.spacing, while the default NULL means to use the automatic setting.
rotate	logical; if plotting a segment of < 360 degrees longitude, rotate the plot so that north is up (or south is down) as seen from the mean longitude of the segment.
size.outer	size of the outer (and potential inner) longitude circle and, if plotting a segment, of the outer latitude lines.
plt.lat.axes	logical; shall latitude axes be plotted?
plt.lat.labels	logical; shall latitude labels be plotted? Per default set to the value of plt.lat.axes.
plt.lon.axes	logical; shall longitude axes be plotted?
plt.lon.labels	logical; shall longitude labels be plotted? Per default set to the value of plt.lon.axes.
rotate.long.labels	logical; controls whether the longitude axis labels are rotated according to their value and the setting of rotate (the default) or not.
lat.ax.labs.pos	longitudinal positions of the latitude axis labels. Per default, the labels are placed at 0 E (180 W) for north (south) polar plots or at the mean longitude of a segment; use this parameter to override the default setting.
ax.labs.size	size of latitude and longitude axis labels.
clip	Should drawing be clipped to the extent of the plot panel? A setting of "on" (the default) means yes, and a setting of "off" means no. For details, please see coord_cartesian.
data.layer	optional ggplot2 layer of data onto which the polar map shall be plotted. Defaults to NULL which only plots the map.

Author(s)

Andrew Dolman <[e-mail]> with some modifications by Thomas Münch.

Source

Adapted from Mikey Harper's plot; see https://stackoverflow.com/a/49084793.

Examples

library(ggplot2)
ggpolar(pole = "N", max.lat = 90, min.lat = 55, n.lat.labels = 4)
ggpolar(pole = "S", max.lat = -60, min.lat = -90)

ggpolar(pole = "N", max.lat = 90, min.lat = 55,
               max.lon = 0, min.lon = -80,
               longitude.spacing = 15, n.lat.labels = 5) +
  geom_point(aes(x = -35, y = 75, colour = "sd")) +
  geom_point(aes(x = -35, y = 70, colour = "sf"))


ggpolar(pole = "N", max.lat = 90, min.lat = 55,
               max.lon = 0, min.lon = -80,
               longitude.spacing = 30,
               rotate = TRUE)

ggpolar(pole = "S", max.lat = -55, min.lat = -90,
        max.lon = 80, min.lon = -20,
        longitude.spacing = 30,
        rotate = TRUE)


ggpolar(pole = "N", max.lat = 90, min.lat = 55,
               max.lon = 170, min.lon = -180,
               longitude.spacing = 33)

# set country.outline.colour the same as land.fill.colour to hide political
# boundaries
ggpolar(pole = "N", max.lat = 90, min.lat = 65, n.lat.labels = 4,
 country.outline.colour = "Grey")

## Not run: 
ggpolar(pole = "W", max.lat = -55, min.lat = -90)
ggpolar(pole = "S", max.lat = 90, min.lat = 55)
ggpolar(pole = "S", max.lat = -90, min.lat = -55)

## End(Not run)

EarthSystemDiagnostics/ecustools documentation built on Jan. 15, 2022, 5:22 p.m.