R: Convenience functions for range subsets.

between {data.table}

R Documentation

Convenience functions for range subsets.

Description

Intended for use in i in [.data.table.

between is equivalent to x >= lower & x <= upper when incbounds=TRUE, or x > lower & y < upper when FALSE.

inrange checks whether each value in x is in between any of the intervals provided in lower,upper.

Usage

between(x, lower, upper, incbounds=TRUE)
x %between% y

inrange(x, lower, upper, incbounds=TRUE)
x %inrange% y

Arguments

`x`	Any orderable vector, i.e., those with relevant methods for `<=`, such as `numeric`, `character`, `Date`, etc. in case of `between` and a numeric vector in case of `inrange`.
`lower`	Lower range bound.
`upper`	Upper range bound.
`y`	A length-2 `vector` or `list`, with `y[[1]]` interpreted as `lower` and `y[[2]]` as `upper`.
`incbounds`	`TRUE` means inclusive bounds, i.e., [lower,upper]. `FALSE` means exclusive bounds, i.e., (lower,upper). It is set to `TRUE` by default for infix notations.

Details

From v1.9.8+, between is vectorised. lower and upper are recycled to length(x) if necessary.

non-equi joins were recently implemented in v1.9.8. It extends binary search based joins in data.table to other binary operators including >=, <=, >, <. inrange makes use of this new functionality and performs a range join.

Value

Logical vector as the same length as x with value TRUE for those that lie within the specified range.

Note

Current implementation does not make use of ordered keys for %between%.

Examples

X = data.table(a=1:5, b=6:10, c=c(5:1))
X[b %between% c(7,9)]
X[between(b, 7, 9)] # same as above
# NEW feature in v1.9.8, vectorised between
X[c %between% list(a,b)]
X[between(c, a, b)] # same as above
X[between(c, a, b, incbounds=FALSE)] # open interval

# inrange()
Y = data.table(a=c(8,3,10,7,-10), val=runif(5))
range = data.table(start = 1:5, end = 6:10)
Y[a %inrange% range]
Y[inrange(a, range$start, range$end)] # same as above
Y[inrange(a, range$start, range$end, incbounds=FALSE)] # open interval

[Package data.table version 1.11.4 Index]