ChemoSpec (version 4.0.1)

chooseLvls: Select Levels for Contour and Image Type Plots

Description

Given a matrix, this function will assist in selecting levels for preparing contour and image type plots. For instance, levels can be spaced evenly, logrithmically, or exponentially.

Usage

chooseLvls(M, n = 10, mode = "even", lambda = 1, base = 2, showHist = FALSE, ...)

Arguments

M

A numeric matrix.

n

For all methods except ecdf, an integer giving the number of levels desired. For ecdf, n should be one or more values in the interval (0...1). For instance, a value of 0.6 corresponds to a single level in which 60

mode

Character. One of c("even", "log", "exp", "ecdf", "posexp", "negexp", "poslog", "neglog"). "even" will create evenly spaced levels. "log" will create levels which are more closely spaced at the extremes, while

lambda

Numeric. A non-zero exponent used with method = "exp" and relatives.

base

Integer. The base used with method = "log" and relatives.

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.

References

https://github.com/bryanhanson/ChemoSpec

Examples

set.seed(9)
MM <- matrix(runif(100, -1, 1), nrow = 10) # test data
tsts <- c("even", "log", "exp", "ecdf", "poslog", "posexp")
for (i in 1:length(tsts)) {
	nl <- 10
	if(tsts[i] == "ecdf")  nl <- seq(0.1, 0.9, 0.1)
	levels <- chooseLvls(M = MM, n = nl, mode = tsts[i], showHist = TRUE)
	}