head {edgeR} | R Documentation

## Return the First to Last Part of a Data Object

### Description

Retrieve the first or last parts of a DGEList, DGEExat, DGEGLM, DGELRT or TopTags object.

### Usage

    ## S3 method for class 'DGEList'
    head(x, n = 6L, ...)
    ## S3 method for class 'DGEList'
    tail(x, n = 6L, ...)

### Arguments

`x` | an object of class `DGEList`, `DGEExact`, `DGEGLM`, `DGELRT` or `TopTags`.
`n` | a single integer. If positive or zero, number rows of resulting object. If negative, all but the `n` last/first rows of `x`.
`...` | other arguments are not currently used.

### Details

`head` (`tail`) returns the first (last) `n` rows when `n >= 0` or all but the last (first) `n` rows when `n < 0`.

### Value

An object like `x` but generally with fewer rows.

### Author(s)

Gordon Smyth

### See Also

`head` in the utils package or `head.EList` in the limma package.

### Examples

    Counts <- matrix(rpois(40,lambda=10),20,2)
    rownames(Counts) <- paste0("Gene",1:20)
    colnames(Counts) <- c("A","B")
    y <- DGEList(Counts)
    head(y)
    tail(y)

[Package edgeR version 3.34.1 Index]