xyz.coords {graphics} R Documentation

## Extracting Plotting Structures

### Description

Utility for obtaining consistent x, y and z coordinates and labels for three dimensional (3D) plots.

### Usage

```xyz.coords(x, y, z, xlab = NULL, ylab = NULL, zlab = NULL,
log = NULL, recycle = FALSE)
```

### Arguments

 `x, y, z` the x, y and z coordinates of a set of points. Alternatively, a single argument `x` can be provided. In this case, an attempt is made to interpret the argument 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 with three columns, the first is assumed to contain the x values, etc. Alternatively, two arguments `x` and `y` can be provided. 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.

### Value

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`.

### Author(s)

Uwe Ligges and Martin Maechler

`xy.coords` for 2D.

### Examples

```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 ...
```

[Package graphics version 2.1.0 Index]