| bitwise {base} | R Documentation |
Bitwise Logical Operations
Description
Logical operations on integer vectors with elements viewed as sets of bits.
Usage
bitwNot(a)
bitwAnd(a, b)
bitwOr(a, b)
bitwXor(a, b)
bitwShiftL(a, n)
bitwShiftR(a, n)
Arguments
a, b |
integer vectors; numeric vectors are coerced to integer vectors. |
n |
non-negative integer vector of values up to 31. |
Details
Each element of an integer vector has 32 bits.
Pairwise operations can result in integer NA.
Shifting is done assuming the values represent unsigned integers.
Value
An integer vector of length the longer of the arguments, or zero length if one is zero-length.
The output element is NA if an input is NA (after
coercion) or an invalid shift.
See Also
The logical operators, !, &,
|, xor.
Notably these do work bitwise for raw arguments.
The classes "octmode" and "hexmode" whose
implementation of the standard logical operators is based on these
functions.
Package bitops has similar functions for numeric vectors which
differ in the way they treat integers 2^{31} or larger.
Examples
bitwNot(0:12) # -1 -2 ... -13
bitwAnd(15L, 7L) # 7
bitwOr (15L, 7L) # 15
bitwXor(15L, 7L) # 8
bitwXor(-1L, 1L) # -2
## The "same" for 'raw' instead of integer :
rr12 <- as.raw(0:12) ; rbind(rr12, !rr12)
c(r15 <- as.raw(15), r7 <- as.raw(7)) # 0f 07
r15 & r7 # 07
r15 | r7 # 0f
xor(r15, r7)# 08
bitwShiftR(-1, 1:31) # shifts of 2^32-1 = 4294967295