Round {base} | R Documentation |

`ceiling`

takes a single numeric argument `x`

and returns a
numeric vector containing the smallest integers not less than the
corresponding elements of `x`

.

`floor`

takes a single numeric argument `x`

and returns a
numeric vector containing the largest integers not greater than the
corresponding elements of `x`

.

`trunc`

takes a single numeric argument `x`

and returns a
numeric vector containing the integers formed by truncating the values in
`x`

toward `0`

.

`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.

`zapsmall`

determines a `digits`

argument `dr`

for
calling `round(x, digits = dr)`

such that values “close to
zero” (compared with the maximal absolute value) are “zapped”,
i.e., treated as `0`

.

ceiling(x) floor(x) trunc(x) round(x, digits = 0) signif(x, digits = 6) zapsmall(x, digits = getOption("digits"))

`x` |
a numeric vector. A complex vector is allowed for
`round` , `signif` and `zapsmall` . |

`digits` |
integer indicating the precision to be used. |

All but `zapsmall`

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 `round(0.5)`

is `0`

and `round(-1.5)`

is
`-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
`0.1`

or `0.2`

).

For `signif`

the recognized values of `digits`

are
`1...22`

. 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.

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)
*The New S Language*.
Wadsworth & Brooks/Cole. (Except `zapsmall`

.)

Chambers, J. M. (1998)
*Programming with Data. A Guide to the S Language*.
Springer. (`zapsmall`

.)

round(.5 + -2:4) # IEEE rounding: -2 0 0 2 2 4 4 ( x1 <- seq(-2, 4, by = .5) ) round(x1)#-- IEEE rounding ! x1[trunc(x1) != floor(x1)] x1[round(x1) != floor(x1 + .5)] (non.int <- ceiling(x1) != floor(x1)) x2 <- pi * 100^(-1:3) round(x2, 3) signif(x2, 3) print (x2 / 1000, digits=4) zapsmall(x2 / 1000, digits=4) zapsmall(exp(1i*0:4*pi/2))

[Package *base* version 2.5.0 Index]