round() and negative digits
On 09-Oct-11 00:46:58, Carl Witthoft wrote:
On 10/8/11 6:11 PM, (Ted Harding) wrote:
Carl Witthoft's serendipitous discovery is a nice example of how secrets can be guessed by wondering "what if ... ?". So probably you don;t need to tell the secrets. Taking the "negative digits" to their logical extreme: round(654.321,2) # [1] 654.32 round(654.321,1) # [1] 654.3 round(654.321,0) # [1] 654 round(654.321,-1) # [1] 650 round(654.321,-2) # [1] 700 round(654.321,-3) # [1] 1000 round(654.321,-4) # [1] 0 which is what you'd logically expect (but is it what you would intuitively expect?).
Oh, oh, somebody's going all metaphysical on us.
Nor should one forget the rounding rules (not OS-dependent in this case, I think ... ?): round(5000,-4) # [1] 0 round(15000,-4) # [1] 20000 Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <ted.harding at wlandres.net> Fax-to-email: +44 (0)870 094 0861 Date: 09-Oct-11 Time: 08:59:58 ------------------------------ XFMail ------------------------------