| 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.
as.double attempts to coerce its argument to be of double
type: like as.vector it strips attributes including
names. Character strings containing either a decimal representation or a
heaxadecimal representation (starting with 0x or 0X) can
be converted.
is.double returns TRUE or FALSE depending on
whether its argument is of double type or not. It is generic:
you can write methods to handle specific classes of objects, see
InternalMethods.
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.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
is.double(1) all(double(3) == 0)