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Flexible Formatting

Usage

formatC(x, digits = NULL, width = max(0, digits) + 1,
        format = NULL, flag = "", mode = NULL)

Arguments

x an atomic numerical or character object, typically a vector of real numbers.
digits the desired number of digits after the decimal point. Default: 2 for integer, 4 for real numbers. If less than 0, the C default of 6 digits is used.
width the total field width; width < 0 means left justify the number in this field (equivalent to flag ="-"). It is possible that the result will be longer than this, but that should only happen in reasonable cases.
format equal to "d" (for integers), "f", "e", "E", "g", "G" (for reals), or "s" (for strings). "f" gives numbers in the usual ``xxx.xxx'' format; "e" and "E" give ``n.dddenn'' or ``n.dddEnn'' (scientific format); "g" and "G" put x[i] into scientific format only if it saves space to do so.
flag format modifier as in Kernighan and Ritchie, 2nd ed., page 243. "0" pads leading zeros; "-" does left adjustment, others are "+", " ", and "#".
mode "real", "integer" or "character". Default: Automatic.

Value

A character object of same size and attributes as x. Unlike format, each number is formatted individually. A for loop over each element of x, calling sprintf(...) is done in the C function str_signif.

For character arguments x, simple (left or right) padding with white space is done.

Author(s)

Originally written by Bill Dunlap, later much improved by Martin Maechler, it was adapted for R by Friedrich Leisch.

See Also

format.

Examples

xx  <- pi * 10^(-5:4)
options(digits = 4)   # only for format
cbind(format(xx), formatC(xx))
cbind(formatC(xx, wid = 9, flag = "-"))
cbind(formatC(xx, dig = 5, wid = 8, format = "f", flag = "0"))

formatC(c("a", "Abc", "no way"), wid = -7)  # <=> flag = "-"