gcf_grid {ContourFunctions} | R Documentation |

## Create contour plot from grid data using ggplot2

### Description

The same as cf_grid_screen but uses ggplot2 for the plot.

### Usage

```
gcf_grid(x = seq(0, 1, length.out = nrow(z)), y = seq(0, 1, length.out
= ncol(z)), z, xlim = range(x, finite = TRUE), ylim = range(y, finite
= TRUE), zlim = range(z, finite = TRUE), with_lines = FALSE,
lines_only = FALSE, bins = 8, interpolate = TRUE,
levels = pretty(zlim, nlevels), nlevels = 20,
color.palette = cm.colors.strong, col = color.palette(length(levels)
- 1), asp = NA, las = 1, bar = F, pts = NULL, reset.par = TRUE,
pretitle = "", posttitle = "", main = NULL, mainminmax = !bar,
mainminmax_minmax = TRUE, afterplotfunc = NULL,
cex.main = par()$cex.main, ...)
```

### Arguments

`x` |
x values, must form grid with y. If not given, it is assumed to be from 0 to 1. |

`y` |
y values, must form grid with x. If not given, it is assumed to be from 0 to 1. |

`z` |
z values at grid locations |

`xlim` |
x limits for the plot. |

`ylim` |
y limits for the plot. |

`zlim` |
z limits for the plot. |

`with_lines` |
Should lines be added on top of contour to show contours? |

`lines_only` |
Should no fill be used, only contour lines? |

`bins` |
Number of lines used when using 'with_lines' or 'lines_only' |

`interpolate` |
Will smooth out contours |

`levels` |
a set of levels which are used to partition the range of z. Must be strictly increasing (and finite). Areas with z values between consecutive levels are painted with the same color. |

`nlevels` |
if levels is not specified, the range of z, values is divided into approximately this many levels. |

`color.palette` |
a color palette function to be used to assign colors in the plot. Defaults to cm.colors. Other options include rainbow, heat.colors, terrain.colors, topo.colors, and function(x) gray((1:x)/x). |

`col` |
an explicit set of colors to be used in the plot. This argument overrides any palette function specification. There should be one less color than levels |

`asp` |
the y/x aspect ratio, see plot.window. |

`las` |
the style of labeling to be used. The default is to use horizontal labeling. |

`bar` |
Should a bar showing the output range and colors be shown on the right? |

`pts` |
Points to plot on top of contour |

`reset.par` |
Should the graphical parameters be reset before exiting? Usually should be unless you need to add something to the plot afterwards and bar is TRUE. |

`pretitle` |
Text to be preappended to end of plot title |

`posttitle` |
Text to be appended to end of plot title |

`main` |
Title for the plot |

`mainminmax` |
whether the min and max values should be shown in the title of plot |

`mainminmax_minmax` |
Whether [min,max]= should be shown in title or just the numbers |

`afterplotfunc` |
Function to call after plotting, such as adding points or lines. |

`cex.main` |
The size of the main title. 1.2 is default. |

`...` |
additional graphical parameters, currently only passed to title(). |

### Value

ggplot2 object

### Examples

```
x <- y <- seq(-4*pi, 4*pi, len = 27)
r <- sqrt(outer(x^2, y^2, "+"))
gcf_grid(cos(r^2)*exp(-r/(2*pi)))
gcf_grid(r, color.palette=heat.colors, bar=TRUE)
gcf_grid(r, color.palette=function(x) {gray((1:x)/x)}, bar=TRUE)
```

*ContourFunctions*version 0.1.1 Index]