Arithmetic convenience operators

%+-% builds a tolerance interval: x %+-% y returns c(x - y, x + y), which slots straight into the "between" operators in comparisons. %/0% is a safe division that returns NA instead of Inf/NaN when dividing by zero, so a stray zero will not poison a downstream sum or mean.

Usage

x %+-% y

x %/0% y

Arguments

x

a numeric value (or vector)

y

a numeric value (or vector)

Value

%+-% returns a length-2 numeric vector c(lower, upper); %/0% returns x / y with any divide-by-zero results replaced by NA.

Author

Ben Wiseman, benjamin.h.wiseman@gmail.com

Examples

5 %+-% 0.5             # 4.5 5.5
#> [1] 4.5 5.5
4.9 %><% (5 %+-% 0.5)  # TRUE  - composes with the 'between' operator
#> [1] TRUE

10 %/0% 2                    # 5
#> [1] 5
10 %/0% 0                    # NA (not Inf)
#> [1] NA
c(1, 2, 3) %/0% c(1, 0, 3)   # 1 NA 1
#> [1]  1 NA  1