Bin-average f=f(x,y)

Average the values of a vector f(x,y) in bins defined on vectors x and y. A common example might be averaging spatial data into location bins.

Usage

binMean2D(
  x,
  y,
  f,
  xbreaks,
  ybreaks,
  flatten = FALSE,
  fill = FALSE,
  fillgap = -1,
  include.lowest = FALSE,
  na.rm = FALSE,
  debug = getOption("oceDebug")
)

Arguments

x

vector of numerical values.

y

vector of numerical values.

f

Matrix of numerical values, a matrix f=f(x,y).

xbreaks

Vector of values of x at the boundaries between bins, calculated using pretty(x) if not supplied.

ybreaks

Vector of values of y at the boundaries between bins, calculated using pretty(y) if not supplied.

flatten

a logical value indicating whether the return value also contains equilength vectors x, y, z and n, a flattened representation of xmids, ymids, result and number.

fill, fillgap

values controlling whether to attempt to fill gaps (that is, regions of NA values) in the matrix. If fill is false, gaps, or regions with NA values, are not altered. If fill is TRUE, then gaps that are of size less than or equal to fillgap are interpolated across, by calling fillGapMatrix() with the supplied value of fillgap.

include.lowest

logical value indicating whether to include y values for which the corresponding x is equal to xmin. See “Details”.

na.rm

logical value indicating whether to remove NA values before doing the computation of the average. This is passed to mean(), which does the work of the present function.

debug

an integer specifying whether debugging information is to be printed during the processing. This is a general parameter that is used by many oce functions. Generally, setting debug=0 turns off the printing, while higher values suggest that more information be printed. If one function calls another, it usually reduces the value of debug first, so that a user can often obtain deeper debugging by specifying higher debug values.

Value

By default, i.e. with flatten being FALSE, binMean2D() returns a list with the following elements: xmids, a vector holding the x-bin midpoints; ymids, a vector holding the y-bin midpoints; number, a matrix holding the number the points in each bin; and result, a matrix holding the mean value in each bin. If flatten is TRUE, the number and result matrices are renamed as n and f and transformed to vectors, while the bin midpoints are renamed as x and y and extended to match the length of n and f.

See also

Other bin-related functions: binApply1D(), binApply2D(), binAverage(), binCount1D(), binCount2D(), binMean1D()

Author

Dan Kelley

Examples

library(oce)
x <- runif(500, 0, 0.5)
y <- runif(500, 0, 0.5)
f <- x^2 + y^2
xb <- seq(0, 0.5, 0.1)
yb <- seq(0, 0.5, 0.1)
m <- binMean2D(x, y, f, xb, yb)
cm <- colormap(f, col = oceColorsTurbo)
opar <- par(no.readonly = TRUE)
drawPalette(colormap = cm)
plot(x, y, col = cm$zcol, pch = 20, cex = 1.4)
contour(m$xmids, m$ymids, m$result, add = TRUE, labcex = 1.4)

par(opar)