xyz.coords {grDevices}  R Documentation 
Utility for obtaining consistent x, y and z coordinates and labels for three dimensional (3D) plots.
xyz.coords(x, y = NULL, z = NULL, xlab = NULL, ylab = NULL, zlab = NULL, log = NULL, recycle = FALSE)
x, y, z 
the x, y and z coordinates of a set of points.
Both y and z can be left at NULL . In this
case, an attempt is made to interpret x in a way suitable for
plotting.
If the argument is a formula zvar ~ xvar + yvar ,
xvar , yvar and zvar are used as x, y and z
variables;
if the argument is a list containing components x ,
y and z , these are assumed to define plotting coordinates;
if the argument is a matrix or data.frame with three
or more columns, the first is
assumed to contain the x values, the 2nd the y ones, and the 3rd the
z ones – independently of any column names that x may have.
Alternatively two arguments x and y can be provided
(leaving z = NULL ). One may be real, the other complex;
in any other case, the arguments are coerced to vectors
and the values plotted against their indices.

xlab, ylab, zlab 
names for the x, y and z variables to be extracted. 
log 
character, "x" , "y" , "z" or combinations.
Sets negative values to NA and gives a warning. 
recycle 
logical; if TRUE , recycle (rep ) the
shorter ones of x , y or z if their lengths differ. 
A list with the components
x 
numeric (i.e., double ) vector of abscissa values. 
y 
numeric vector of the same length as x . 
z 
numeric vector of the same length as x . 
xlab 
character(1) or NULL , the axis label of x . 
ylab 
character(1) or NULL , the axis label of y . 
zlab 
character(1) or NULL , the axis label of z . 
Uwe Ligges and Martin Maechler
xy.coords
for 2D.
xyz.coords(data.frame(10*1:9, 4), y = NULL, z = NULL) xyz.coords(1:6, stats::fft(1:6), z = NULL, xlab = "X", ylab = "Y") y < 2 * (x2 < 10 + (x1 < 1:10)) xyz.coords(y ~ x1 + x2, y = NULL, z = NULL) xyz.coords(data.frame(x = 1:9, y = 2:12, z = 3:13), y = NULL, z = NULL, log = "xy") ##> Warning message: 2 x values <= 0 omitted ...