numeric {base}

R Documentation

Numeric Vectors

Description

numeric creates a real vector of the specified length. The elements of the vector are all equal to 0.

as.numeric attempts to coerce its argument to numeric type (either integer or real).

is.numeric returns TRUE if its argument is of type real or type integer and FALSE otherwise.

Usage

numeric(length = 0)
as.numeric(x, ...)
is.numeric(x)

Arguments

length	desired length.
x	object to be coerced or tested.
...	further arguments passed to or from other methods.

Note

R has no single precision data type. All real numbers are stored in double precision format. While as.numeric is a generic function, user methods must be written for as.double, which it calls

as.numeric for factors yields the codes underlying the factor levels, not the numeric representation of the labels.

Examples

as.numeric(c("-.1"," 2.7 ","B")) # (-0.1, 2.7, NA)  +  warning
as.numeric(factor(5:10))

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