Create a plot object for a CFVariable — geom

This is a basic function to support plotting of ncdfCF data with the ggplot2 package. Specifically, this function creates a geo_ncdf object which can be used like a geom_raster. The geom_ncdf takes a CFVariable instance as its data. The CFVariable should be properly pre-processed to make it suitable for plotting. The $subset() method is well suited for this task. Note that currently only map plotting works, e.g. the CFVariable should have X and Y axes.

Usage

geom_ncdf(mapping = NULL, data, ...)

Arguments

mapping: As in geom_raster. If the argument is not provided, a mapping is constructed from the properties of the data argument, which is usually the right way.
data: A CFVariable instance. This will override any data setting of the ggplot() function.
...: Arguments passed on to geom_raster().

Value

A geom_* object that can be used in ggplot2 plot composition.

Examples

library(ggplot2)
fn <- system.file("extdata", "tasmax_NAM-44_day_20410701-vncdfCF.nc", package = "ncdfCF")
ds <- open_ncdf(fn)
tasmax <- ds[["tasmax"]]
ggplot() + geom_ncdf(data = tasmax) + coord_equal() + scale_fill_viridis_c()