Re: fractional cents

* Bernie Cosell <[email protected]> [2004-04-19 17:37]:
> So: what I want is something to format money correctly, whther
> it is fractional or not.  there's the fairly awful:
> 
>      sprintf ($amt =~ /\.\d\d\d/? "%7.3f": "%7.2f"), $amt

Right off the bat I thought of %g, but that doesn't really help:

    $ perl -e'printf "%7.4g\n", $_ for 1.2, 1.23, 1.234, 1.2345'
        1.2
       1.23
      1.234
      1.234

When testing $amt itself, I'd insist on using mathematical
functions only for the sake of cleanliness -- you never know when
stringification would surprise you. Unfortunately, getting the
fractional part of a number in Perl is verbose using mathematical
functions.

So instead I'd say to do string mangling on the end result, which
is only a string representation of $amt anyway:

    my $amt_str = sprintf "%7.3f", $amt;
    for($amt_str) { chop if /\.\d\d0\z/ } 

Test:

    perl -le'for (@ARGV) { $_ = sprintf "%7.3f", $_; \
    chop if /\.\d\d0\z/; print; }' 1.2, 1.23, 1.234, 1.2345
      1.20
      1.23
      1.234
      1.234
        
It's not shorter or more obvious I'm afraid, just a little more
correct.

-- 
Regards,
Aristotle
 
"If you can't laugh at yourself, you don't take life seriously enough."