Operators To Check, If a Value Lies Within Or Outside a Given Range
The between and outside operators are used to check, whether a vector of given values x lie within a defined range (or outside respectively). The values can be numbers, text or dates. Ordered factors are supported.
x %()% rng x %(]% rng x %[)% rng x %[]% rng x %][% rng x %](% rng x %)[% rng x %)(% rng x %:% rng x %::% rng
x |
is a variable with at least ordinal scale, usually a numeric value, but can be an ordered factor or a text as well. Texts would be treated alphabetically. |
rng |
a vector of two values or a matrix with 2 columns, defining the minimum and maximum of the range for x. |
The "BETWEEN" operators basically combine two conditional statements into one and simplify the query process.
They are merely a wrapper for: x >= rng[1] & x <= rng[2],
where the round bracket ( means strictly greater (>) and the square bracket [ means greater or equal (>=). Numerical values of x will be handled by C-code, which is significantly faster than two comparisons in R (especially when x is huge).
.%][% is the negation of %()%, meaning all values lying outside the given range. Elements on the limits will return TRUE.
%:% returns all the elements of a vector between the (first found) element rng[1] and rng[2]. If no match is found it returns NA. If rng[2] occurs before rng[1] in the vector the elements will be returned in reverse order (which is the same behaviour as the : operator).
%::% does the same in greedy mood. It uses the first match for from and the last match for to.
A logical vector of the same length as x.
Andri Signorell <andri@signorell.net> based on C-code by Kevin Ushey <kevinushey@gmail.com>
x <- 1:9
x %[]% c(3,5)
# outside
x <- 1:9
x %][% c(3,5)
c(x,NA) %[]% c(3,5)
x %(]% c(3,5)
# no result when from > to:
x %[]% c(5,3)
x %(]% c(5,5)
# no problem:
ordered(x) %[]% c(3,5)
# not meaningful:
factor(x) %[]% c(3,5)
# characters
letters[letters %(]% c("d","h")]
data(d.pizza)
x <- levels(d.pizza$driver)
x %[]% c("C","G")
# select diamonds with a price between 2400 and 2510
data(d.diamonds)
d.diamonds[d.diamonds$price %[]% c(2400,2510),]
# use it with an ordered factor and select all diamonds with
# symmetry between G (included) and X (excluded).
mean(d.diamonds[d.diamonds$symmetry %[)% c("G","X"),"price"])
# use multiple ranges
2 %[]% cbind(1:4,2:5)
# both arguments are recycled
c(2,3) %[]% cbind(1:4,2:5)
# between operator for vector positions
set.seed(4)
(x <- sample(LETTERS, size=10, replace=TRUE))
# [1] "X" "K" "S" "C" "G" "L" "S" "V" "U" "Z"
# return all elements between "S" and "L"
x %:% c("S","L")
# [1] "S" "C" "G" "L"
x %:% c("S","A")
# [1] "S" "C" "G" "L" "S" "V" "U" "Z"
x %:% c("A","S")
# [1] "X" "K" "S"
# reverted matches return the elements in reverse order
x %:% c("G","X")
# [1] "G" "C" "S" "K" "X"
# no match results in NA
x %:% c("Y","B")
(x <- c("B", "A", "X", "K", "S", "K", "G", "L", "K", "V", "K", "Z"))
# lazy
x %:% c("A", "K")
# greedy
x %::% c("A", "K")Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.