strtoi Convert Strings to Integers

Description

Convert strings to integers according to the given base using the C function strtol, or choose a suitable base following the C rules.

Usage

strtoi(x, base = 0L)

Arguments

x	a character vector, or something coercible to this by as.character.
base	an integer which is between 2 and 36 inclusive, or zero (default).

Details

Conversion is based on the C library function strtol.

For the default base = 0L, the base chosen from the string representation of that element of x, so different elements can have different bases (see the first example). The standard C rules for choosing the base are that octal constants (prefix 0 not followed by x or X) and hexadecimal constants (prefix 0x or 0X) are interpreted as base 8 and 16; all other strings are interpreted as base 10.

For a base greater than 10, letters a to z (or A to Z) are used to represent 10 to 35.

Value

An integer vector of the same length as x. Values which cannot be interpreted as integers or would overflow are returned as NA_integer_.

See Also

For decimal strings as.integer is equally useful.

Examples

strtoi(c("0xff", "077", "123"))
strtoi(c("ffff", "FFFF"), 16L)
strtoi(c("177", "377"), 8L)