pl2curves {DPQ}

Plot 2 Noncentral Distribution Curves for Visual Comparison

Description

Plot two noncentral (chi-squared or t or ..) distribution curves for visual comparison.

Usage

pl2curves(fun1, fun2, df, ncp, log = FALSE,
          from = 0, to = 2 * ncp, p.log = "", n = 2001,
          leg = TRUE, col2 = 2, lwd2 = 2, lty2 = 3, ...)

Arguments

fun1, fun2

function()s, both to be used via curve(), and called with the same 4 arguments, (., df, ncp, log) (the name of the first argument is not specified).

df, ncp, log

parameters to be passed and used in both functions, which hence typically are non-central chi-squared or t density, probability or quantile functions.

from, to

numbers determining the x-range, passed to curve().

p.log

string, passed as curve(...., log = log.p).

n

the number of evaluation points, passed to curve().

leg

logical specifying if a legend() should be drawn.

col2, lwd2, lty2

color, line width and line type for the second curve. (The first curve uses defaults for these graphical properties.)

...

further arguments passed to first curve(..) call.

Value

TODO: inivisible return both curve() results, i.e., (x,y1, y2), possibly as data frame

Author(s)

Martin Maechler

See Also

curve, ..

Examples

p.dnchiBessel <- function(df, ncp, log=FALSE, from=0, to = 2*ncp, p.log="", ...)
{
    pl2curves(dnchisqBessel, dchisq, df=df, ncp=ncp, log=log,
              from=from, to=to, p.log=p.log, ...)
}

  ## TODO the p.dnchiB()  examples  >>>>>> ../tests/chisq-nonc-ex.R <<<