| double {base} | R Documentation |
Create, coerce to or test for a double-precision vector.
double(length = 0) as.double(x, ...) is.double(x) single(length = 0) as.single(x, ...)
length |
desired length. |
x |
object to be coerced or tested. |
... |
further arguments passed to or from other methods. |
double creates a double-precision vector of the specified
length. The elements of the vector are all equal to 0.
It is identical to numeric (and real).
as.double is a generic function. It is identical to
as.numeric (and as.real).
is.double is a test of double type.
R has no single precision data type. All real numbers are
stored in double precision format. The functions as.single
and single are identical to as.double and double
except they set the attribute Csingle that is used in the
.C and .Fortran interface, and they are
intended only to be used in that context.
double creates a double-precision vector of the specified
length. The elements of the vector are all equal to 0.
as.double attempts to coerce its argument to be of double
type: like as.vector it strips attributes including
names. (To ensure that an object is of double type without
stripping attributes, use storage.mode.)
Character strings containing either a decimal representation or a
hexadecimal representation (starting with 0x or 0X) can
be converted. as.double for factors yields the codes underlying
the factor levels, not the numeric representation of the labels, see
also factor.
is.double returns TRUE or FALSE depending on
whether its argument is of double type or not.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
integer, numeric, storage.mode.
is.double(1) all(double(3) == 0)