calcLvls {ChemoSpec2D}  R Documentation 
Calculate Levels for Contour and Image Type Plots
Description
Given a matrix or vector input, this function will assist in selecting levels for preparing
contour and image type plots. For instance, levels can be spaced evenly,
logrithmically, exponentially or using a cumulative distribution function.
NA
values are ignored.
Usage
calcLvls(
M,
n = 10,
mode = "even",
lambda = 1.5,
base = 2,
showHist = FALSE,
...
)
Arguments
M 
A numeric matrix or vector. 
n 
An integer giving the number of levels desired:

mode 
Character. One of 
lambda 
Numeric. A nonzero exponent used with 
base 
Integer. The base used with 
showHist 
Logical. Shall a histogram be drawn showing the location of the chosen levels? 
... 
Arguments to be passed downstream. 
Value
A numeric vector giving the levels.
Author(s)
Bryan A. Hanson, DePauw University. hanson@depauw.edu
Examples
set.seed(9)
MM < matrix(runif(100, 1, 1), nrow = 10) # test data
tsts < c("even", "log", "poslog", "exp", "posexp", "ecdf", "NMR")
for (i in 1:length(tsts)) {
nl < 20
if (tsts[i] == "ecdf") nl < seq(0.1, 0.9, 0.1)
levels < calcLvls(
M = MM, n = nl, mode = tsts[i],
showHist = TRUE, main = tsts[i]
)
}