%.6g format not interpretted correctly

[EXT-Germain, Marvin E]

%.6g format not interpretted correctly

This also affects the "print" statement's handling of numbers, since OFMT =  %.6g.
Test program compares .6g format to .6f and .6e. It should be the same as one of them, but isn't.
Execute as:
echo howdy | awk -f testProgram

Gawk version 3.1.3

Red Hat Linux uname -r = 2.6.9-42.ELsmp

TEST PROGRAM:

{
   A = 123.456789;

   print "Value = 123.456789";

   printf "Format = .6f ==> %.6f\n", A;

   printf "Format = .6e ==> %.6e\n", A;

   printf "Format = .6g ==> %.6g\n", A;

   printf "\n";

   A = 12.3456789;

   print "Value = 12.3456789";

   printf "Format = .6f ==> %.6f\n", A;

   printf "Format = .6e ==> %.6e\n", A;

   printf "Format = .6g ==> %.6g\n", A;

   print 123.45678;
   print OFMT;
}


OUTPUT:

Value = 123.456789
Format = .6f ==> 123.456789
Format = .6e ==> 1.234568e+02
Format = .6g ==> 123.457

Value = 12.3456789
Format = .6f ==> 12.345679
Format = .6e ==> 1.234568e+01
Format = .6g ==> 12.3457

[Eric Blake]

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According to EXT-Germain, Marvin E on 9/24/2009 1:15 PM:
> %.6g format not interpretted correctly
>
> This also affects the "print" statement's handling of numbers, since OFMT =  %.6g.
> Test program compares .6g format to .6f and .6e. It should be the same as one of them,

Not a bug.  POSIX is explicit that in printf formatting, for .6g, 6
specified the number of significant digits; but for .6f and .6e it
specifies the number of digits after the decimal (which is not necessarily
the number of significant digits).

- --
Don't work too hard, make some time for fun as well!

Eric Blake             ebb9@...
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