hist2: Bivariate histogram

In squash: Color-Based Plots for Multivariate Visualization

Description

Calculate data for a bivariate histogram and (optionally) plot it as a colorgram.

Usage

hist2(x, y = NULL, 
      nx = 50, ny = nx,  
      xlim = NULL, ylim = NULL, 
      xbreaks = NULL, ybreaks = NULL,
      plot = TRUE, 
      xlab = NULL, ylab = NULL, zlab = "Counts", 
      colFn = heat, breaks = prettyInt, ...) 

Arguments

x, y	Numeric vectors.
nx, ny	Approximate number of intervals along x and y axes.
xlim, ylim	Limit the range of data points considered.
xbreaks, ybreaks	Breakpoints between bins along x and y axes.
plot	Plot the histogram?
xlab, ylab	Axis labels.
zlab	Label for the color key.
colFn, breaks	Color key parameters; see makecmap.
...	Further arguments passed to colorgram.

Details

Data can be passed to hist2 in any form recognized by xy.coords (e.g. individual vectors, list, data frame, formula).

Value

Invisibly, a list with components:

x	Vector of breakpoints along the x-axis.
y	Vector of breakpoints along the y-axis.
z	Matrix of counts.
xlab	A label for the x-axis.
ylab	A label for the y-axis.
zlab	A label for the color key.

See Also

hist, for a standard (univariate) histogram.

hist2d in the gplots package for another implementation.

The hexbin package, for a hexagonal implementation.

Examples

  set.seed(123)
  x <- rnorm(10000)
  y <- rnorm(10000) + x
  hist2(x, y)
  
  ## pseudo-log-scale color breaks:
  hist2(x, y, breaks = prettyLog, key.args = list(stretch = 4))

  ## log-scale color breaks; the old way using 'base'
  ## (notice box removal to make space for the vertical color key)
  hist2(x, y, base = 2, key = vkey, nz = 5, bty = 'l')

squash documentation built on Feb. 20, 2020, 9:08 a.m.