stretch {plyranges} | R Documentation

## Stretch a genomic interval

### Description

By default, `stretch(x)` will anchor by the center of a Ranges object. This means that half of the value of `extend` will be added to the end of the range and the remaining half subtracted from the start of the Range. The other anchors will leave the start/end fixed and stretch the end/start respectively.

### Usage

    stretch(x, extend)

### Arguments

`x` | a Ranges object, to fix by either the start, end or center of an interval use `anchor_start(x)`, `anchor_end(x)`, `anchor_center(x)`. To fix by strand use `anchor_3p(x)` or `anchor_5p(x)`.
`extend` | the amount to alter the width of a Ranges object by. Either an integer vector of length 1 or an integer vector the same length as x.

### Value

a Ranges object with modified start or end (or both) coordinates

### See Also

`anchor()`, `mutate()`

### Examples

    rng <- as_iranges(data.frame(start=c(2:-1, 13:15), width=c(0:3, 2:0)))
    rng2 <- stretch(anchor_center(rng), 10)
    stretch(anchor_start(rng2), 10)
    stretch(anchor_end(rng2), 10)
    grng <- as_granges(data.frame(seqnames = "chr1",
                             strand = c("+", "-", "-", "+", "+", "-", "+"),
                             start=c(2:-1, 13:15),
                             width=c(0:3, 2:0)))
    stretch(anchor_3p(grng), 10)
    stretch(anchor_5p(grng), 10)

[Package plyranges version 1.14.0 Index]