R: Local maxima

peaks {splus2R} | R Documentation

## Local maxima

### Description

Finds the local maxima in a vector, or time series, or in each column of a matrix.

### Usage

    peaks(x, span=3, strict=TRUE)

### Arguments

`x` | vector or matrix.
`span` | a peak is defined as an element in a sequence which is greater than all other elements within a window of width span centered at that element. The default value is 3, meaning that a peak is bigger than both of its neighbors. Default: 3.
`strict` | logical flag: if TRUE, an element must be strictly greater than all other values in its window to be considered a peak. Default: TRUE.

### Value

an object like x of logical values. Values that are TRUE correspond to local peaks in the data.

### See Also

`max`, `cummax`, `pmax`.

### Examples

    x <- as.vector(sunspots)
    z <- peaks(x, span=51)
    plot(x, type="l")
    abline(v=which(z), col="red", lty="dashed")

[Package splus2R version 1.2-2 Index]