grid.layout
Create a Grid Layout
This function returns a Grid layout, which describes a subdivision of a rectangular region.
- Keywords
- dplot
Usage
grid.layout(nrow = 1, ncol = 1,
widths = unit(rep_len(1, ncol), "null"),
heights = unit(rep_len(1, nrow), "null"),
default.units = "null", respect = FALSE,
just="centre")Arguments
- nrow
An integer describing the number of rows in the layout.
- ncol
An integer describing the number of columns in the layout.
- widths
A numeric vector or unit object describing the widths of the columns in the layout.
- heights
A numeric vector or unit object describing the heights of the rows in the layout.
- default.units
A string indicating the default units to use if
widthsorheightsare only given as numeric vectors.- respect
A logical value or a numeric matrix. If a logical, this indicates whether row heights and column widths should respect each other. If a matrix, non-zero values indicate that the corresponding row and column should be respected (see examples below).
- just
A string or numeric vector specifying how the layout should be justified if it is not the same size as its parent viewport. If there are two values, the first value specifies horizontal justification and the second value specifies vertical justification. Possible string values are:
"left","right","centre","center","bottom", and"top". For numeric values, 0 means left alignment and 1 means right alignment. NOTE that in this context,"left", for example, means align the left edge of the left-most layout column with the left edge of the parent viewport.
Details
The unit objects given for the widths and heights
of a layout may use a special units that only has
meaning for layouts. This is the "null" unit, which
indicates what relative fraction of the available width/height the
column/row occupies. See the reference for a better description
of relative widths and heights in layouts.
Value
A Grid layout object.
WARNING
This function must NOT be confused with the base R graphics function
layout. In particular, do not use layout in
combination with Grid graphics. The documentation for
layout may provide some useful information and this
function should behave identically in comparable situations. The
grid.layout
function has added the ability to specify a broader range
of units for row heights and column widths, and allows for nested
layouts (see viewport).
References
Murrell, P. R. (1999). Layouts: A Mechanism for Arranging Plots on a Page. Journal of Computational and Graphical Statistics, 8, 121--134. 10.2307/1390924.
See Also
Examples
library(grid)
# NOT RUN {
## A variety of layouts (some a bit mid-bending ...)
layout.torture()
## Demonstration of layout justification
grid.newpage()
testlay <- function(just="centre") {
pushViewport(viewport(layout=grid.layout(1, 1, widths=unit(1, "inches"),
heights=unit(0.25, "npc"),
just=just)))
pushViewport(viewport(layout.pos.col=1, layout.pos.row=1))
grid.rect()
grid.text(paste(just, collapse="-"))
popViewport(2)
}
testlay()
testlay(c("left", "top"))
testlay(c("right", "top"))
testlay(c("right", "bottom"))
testlay(c("left", "bottom"))
testlay(c("left"))
testlay(c("right"))
testlay(c("bottom"))
testlay(c("top"))
# }