ceiling takes a single numeric argument
x and returns a numeric vector containing the smallest integers not less than the corresponding elements of
floor takes a single numeric argument
x and returns a numeric vector containing the largest integers not greater than the corresponding elements of
trunc takes a single numeric argument
x and returns a numeric vector containing the integers formed by truncating the values in
round rounds the values in its first argument to the specified number of decimal places (default 0).
signif rounds the values in its first argument to the specified number of significant digits.
ceiling(x) floor(x) trunc(x, ...) round(x, digits = 0) signif(x, digits = 6)
These are generic functions: methods can be defined for them individually or via the
Math group generic.
Note that for rounding off a 5, the IEC 60559 standard is expected to be used, ‘go to the even digit’. Therefore
-2. However, this is dependent on OS services and on representation error (since e.g.
0.15 is not represented exactly, the rounding rule applies to the represented number and not to the printed number, and so
round(0.15, 1) could be either
Rounding to a negative number of digits means rounding to a power of ten, so for example
round(x, digits = -2) rounds to the nearest hundred.
signif the recognized values of
1...22, and non-missing values are rounded to the nearest integer in that range. Complex numbers are rounded to retain the specified number of digits in the larger of the components. Each element of the vector is rounded individually, unlike printing. These are all primitive functions.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
Documentation reproduced from R 2.15.3. License: GPL-2.