vctrs (version 0.1.0)

vec_arith: Arithmetic operations

Description

This generic provides a common double dispatch mechanism for all infix operators (+, -, /, *, ^, %%, %/%, !, &, |). It is used to power the default arithmetic and boolean operators for vctrs objects, overcoming the limitations of the base Ops generic.

Usage

vec_arith(op, x, y)
# S3 method for default
vec_arith(op, x, y)
# S3 method for logical
vec_arith(op, x, y)
# S3 method for numeric
vec_arith(op, x, y)
vec_arith_base(op, x, y)
MISSING()

Arguments

op

An arithmetic operator as a string

x, y

A pair of vectors. For !, unary + and unary -, y will be a sentinel object of class MISSING, as created by MISSING().

Details

vec_base_arith() is provided as a convenience for writing methods. It recycles x and y to common length then calls the base operator with the underlying vec_data().

vec_arith() is also used in diff.vctrs_vctr() method via -.

See Also

stop_incompatible_op() for signalling that an arithmetic operation is not permitted/supported.

See vec_math() for the equivalent for the unary mathematical functions.

Examples

# NOT RUN {
d <- as.Date("2018-01-01")
dt <- as.POSIXct("2018-01-02 12:00")
t <- as.difftime(12, unit = "hours")

vec_arith("-", dt, 1)
vec_arith("-", dt, t)
vec_arith("-", dt, d)

vec_arith("+", dt, 86400)
vec_arith("+", dt, t)
vec_arith("+", t, t)

vec_arith("/", t, t)
vec_arith("/", t, 2)

vec_arith("*", t, 2)
# }