n2mfrow              package:grDevices              R Documentation

Compute Default mfrow From Number of Plots

Description:

     Easy setup for plotting multiple figures (in a rectangular layout)
     on one page.  This computes a sensible default for 'par(mfrow)'.

Usage:

     n2mfrow(nr.plots)

Arguments:

nr.plots: integer; the number of plot figures you'll want to draw.

Value:

     A length two integer vector 'nr, nc' giving the number of rows and
     columns, fulfilling 'nr >= nc >= 1' and 'nr * nc >= nr.plots'.

Author(s):

     Martin Maechler

See Also:

     'par', 'layout'.

Examples:

     require(graphics)

     n2mfrow(8) # 3 x 3

     n <- 5 ; x <- seq(-2,2, len=51)
     ## suppose now that 'n' is not known {inside function}
     op <- par(mfrow = n2mfrow(n))
     for (j in 1:n)
        plot(x, x^j, main = substitute(x^ exp, list(exp = j)), type = "l",
        col = "blue")

     sapply(1:10, n2mfrow)

