ggplot2 (version 0.9.0)

stat_contour: Calculate contours of 3d data.

Description

Calculate contours of 3d data.

Usage

stat_contour(mapping = NULL, data = NULL, geom = "path",
    position = "identity", na.rm = FALSE, ...)

Arguments

na.rm

If FALSE (the default), removes missing values with a warning. If TRUE silently removes missing values.

mapping

The aesthetic mapping, usually constructed with aes or aes_string. Only needs to be set at the layer level if you are overriding the plot defaults.

data

A layer specific dataset - only needed if you want to override the plot defaults.

geom

The geometric object to use display the data

position

The position adjustment to use for overlappling points on this layer

...

other arguments passed on to layer. This can include aesthetics whose values you want to set, not map. See layer for more details.

Value

• A data frame with additional column:
• level
  height of contour

Examples

# Generate data
library(reshape2) # for melt
volcano3d <- melt(volcano)
names(volcano3d) <- c("x", "y", "z")

# Basic plot
v <- ggplot(volcano3d, aes(x, y, z = z))
v + stat_contour()

# Setting bins creates evenly spaced contours in the range of the data
v + stat_contour(bins = 2)
v + stat_contour(bins = 10)

# Setting binwidth does the same thing, parameterised by the distance
# between contours
v + stat_contour(binwidth = 2)
v + stat_contour(binwidth = 5)
v + stat_contour(binwidth = 10)
v + stat_contour(binwidth = 2, size = 0.5, colour = "grey50") +
  stat_contour(binwidth = 10, size = 1)

# Add aesthetic mappings
v + stat_contour(aes(size = ..level..))
v + stat_contour(aes(colour = ..level..))

# Change scale
v + stat_contour(aes(colour = ..level..), size = 2) +
  scale_colour_gradient(low = "brown", high = "white")

# Set aesthetics to fixed value
v + stat_contour(colour = "red")
v + stat_contour(size = 2, linetype = 4)

# Try different geoms
v + stat_contour(geom="polygon", aes(fill=..level..))
v + geom_tile(aes(fill = z)) + stat_contour()

# Use qplot instead
qplot(x, y, z = z, data = volcano3d, geom = "contour")
qplot(x, y, z = z, data = volcano3d, stat = "contour", geom = "path")