R: format(.) Information

format.info {base}

R Documentation

format(.) Information

Description

Information is returned on how format(x, digits, nsmall) would be formatted.

Usage

format.info(x, digits = NULL, nsmall = 0)

Arguments

`x`	an atomic vector; a potential argument of `format(x, ...)`.
`digits`	how many significant digits are to be used for numeric and complex `x`. The default, `NULL`, uses `getOption(digits)`.
`nsmall`	(see `format(..., nsmall)`).

Value

An integer vector of length 1, 3 or 6, say r.

For logical, integer and character vectors a single element, the width which would be used by format if width = NULL.

For numeric vectors:

`r[1]`	width (in characters) used by `format(x)`
`r[2]`	number of digits after decimal point.
`r[3]`	in `0:2`; if ≥`1`, exponential representation would be used, with exponent length of `r[3]+1`.

For a complex vector the first three elements refer to the real parts, and there are three further elements corresponding to the imaginary parts.

Examples

dd <- options("digits") ; options(digits = 7) #-- for the following
format.info(123)   # 3 0 0
format.info(pi)    # 8 6 0
format.info(1e8)   # 5 0 1 - exponential "1e+08"
format.info(1e222) # 6 0 2 - exponential "1e+222"

x <- pi*10^c(-10,-2,0:2,8,20)
names(x) <- formatC(x, width=1, digits=3, format="g")
cbind(sapply(x,format))
t(sapply(x, format.info))

## using at least 8 digits right of "."
t(sapply(x, format.info, nsmall = 8))

# Reset old options:
options(dd)