colMax: Find row and column maximum values

In sneumann/xcms: LC-MS and GC-MS Data Analysis

Find row and column maximum values

Description

Find row and column maximum values for numeric arrays.

Usage

colMax(x, na.rm = FALSE, dims = 1)
rowMax(x, na.rm = FALSE, dims = 1)
which.colMax(x, na.rm = FALSE, dims = 1)
which.rowMax(x, na.rm = FALSE, dims = 1)

Arguments

x	an array of two or more dimensions, containing numeric values
na.rm	logical. Should missing values (including 'NaN') be omitted from the calculations? (not currently implemented)
dims	Which dimensions are regarded as "rows" or "columns" to maximize. For rowMax, the maximum is over dimensions dims+1, ...; for colMax it is over dimensions 1:dims.

Details

These functions are designed to act like the colSums series of functions except that they only currently handle real arrays and will not remove NA values.

Value

A numeric array of suitable size, or a vector if the result is one-dimensional. The dimnames (or names for a vector result) are taken from the original array.

For the which.* functions, an integer array of suitable size, or a vector if the result is one-dimensional. The indecies returned are for accessing x one-dimensionally (i.e. x[index]). For which.colMax(), the actual row indecies my be determined using (which.colMax(x)-1) %% nrow(x) + 1. For which.rowMax(), the actual column indecies may be determined using ceiling(rowMax(x)/nrow(x)).

Author(s)

Colin A. Smith, [e-mail]

See Also

colSums

sneumann/xcms documentation built on Dec. 19, 2024, 5:22 a.m.