Constants built into R.
LETTERS letters month.abb month.name pi
R has a small number of built-in constants.
The following constants are available:
LETTERS: the 26 upper-case letters of the Roman alphabet;
letters: the 26 lower-case letters of the Roman alphabet;
month.abb: the three-letter abbreviations for the English month names;
month.name: the English names for the months of the year;
pi: the ratio of the circumference of a circle to its diameter.
These are implemented as variables in the base namespace taking appropriate values.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
## John Machin (ca 1706) computed pi to over 100 decimal places ## using the Taylor series expansion of the second term of pi - 4*(4*atan(1/5) - atan(1/239)) ## months in English month.name ## months in your current locale format(ISOdate(2000, 1:12, 1), "%B") format(ISOdate(2000, 1:12, 1), "%b")