| % File src/library/base/man/format.info.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2011 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{format.info} |
| \alias{format.info} |
| \title{format(.) Information} |
| \description{ |
| Information is returned on how \code{\link{format}(x, digits, nsmall)} |
| would be formatted. |
| } |
| \usage{ |
| format.info(x, digits = NULL, nsmall = 0) |
| } |
| \arguments{ |
| \item{x}{an atomic vector; a potential argument of |
| \code{\link{format}(x, \dots)}.} |
| \item{digits}{how many significant digits are to be used for |
| numeric and complex \code{x}. The default, \code{NULL}, uses |
| \code{\link{getOption}("digits")}.} |
| \item{nsmall}{ (see \code{\link{format}(\dots, nsmall)}).} |
| } |
| |
| \value{ |
| An \code{\link{integer}} \code{\link{vector}} of length 1, 3 or 6, say |
| \code{r}. |
| |
| For logical, integer and character vectors a single element, |
| the width which would be used by \code{format} if \code{width = NULL}. |
| |
| For numeric vectors: |
| \item{r[1]}{width (in characters) used by \code{format(x)}} |
| \item{r[2]}{number of digits after decimal point.} |
| \item{r[3]}{in \code{0:2}; if \eqn{\ge}\code{1}, \emph{exponential} |
| representation would be used, with exponent length of \code{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. |
| } |
| \seealso{ |
| \code{\link{format}} (notably about \code{digits >= 16}), |
| \code{\link{formatC}}. |
| } |
| \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) |
| } |
| \keyword{character} |
| \keyword{print} |
| \keyword{programming} |