single
Single Precision Objects
Description
Creates or tests for numeric objects with mode equal to "single".
Usage
single(length = 0L)
is.single(x)
as.single(x, ...)
## Default S3 method:
as.single(x, ...)
Arguments
| length |
the length desired for the resulting object.
|
| x |
any object.
|
| ... |
other arguments to pass to or from other functions.
|
Details
Usually, you need vectors of mode "single" only if you are
using the interface to a Fortran subroutine with arguments that are
declared REAL, or a C function with arguments that are declared float.
(see .Fortran)
Note the difference between using as.single and
mode(x) <- "single". The former strips all attributes; the
latter does not strip attributes (that is, a matrix stays a matrix).
as.single is generic. Only the default method is implemented at present.
Value
| single | returns a simple object of storage mode
"double" and the length specified. It has the attribute
"Csingle" set to TRUE. |
| is.single | always gives an error. |
| as.single.default | returns x if x is a simple object
of mode "single". Otherwise, it returns a simple object of the
same length as x ,and with data resulting from coercing the
elements of x to storage mode "double". Attributes are
replaced with a single attribute "Csingle" set to TRUE. |
See Also
Examples
x <- c(3.14, 92)
# Call a .Fortran routine 'mysub'.
# as.single is used to tell .Fortran to pass x as single-precision
# floating point values
# single(length(x)) is used to create an output buffer for the call
# to fill in.
## Not run:
y <- .Fortran("mysub", as.single(x), single(length(x)))[[2]]
## End(Not run)