I was surprised to see 16 digits after the decimal point in a "%.17" notation. Per perl's sprintf docs:
%g a floating-point number, in %e or %f notation
But that's not what actually happens in Perl:
C:>perl -MConfig -le "print +5.3130431399669280e-34; printf qq($_\n),
++5.3130431399669280e-34 for qw/%.17f %.17e %.17g/; print qq($^V\t|\t$
v5.30.0 | Win32 strawberry-perl 188.8.131.52 #1 Thu May 23 12:20:46
... In this instance, "%.17g" is neither equivalent to "%.17f" (17 digits after the fixed decimal point) nor to "%.17e" (17 digits after the floating decimal point).
I tried on an ancient linux machine with v5.8.5, with similar results:
% perl -MConfig -le 'print +5.3130431399669280e-34; printf qq($_\n), +
+5.3130431399669280e-34 for qw/%.17f %.17e %.17g/; print qq($]\t|\t$Co
5.008005 | linux builder4.centos.org 2.6.9-55.0.9.elsmp #
+1 smp thu sep 27 18:27:41 edt 2007 i686 i686 i386 gnulinux
The sprintf docs have used that phrasing at least as far back as v5.005 . Am I misunderstanding what I'm seeing? or has perl documentation about %g been wrong for that long?
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