------- Comment #3 from furue at hawaii dot edu 2008-01-31 02:00 ------- Subject: Re: illegal E format descriptor produces wrong output
Hi, | ------- Comment #2 from kargl at gcc dot gnu dot org 2008-01-31 01:46 ------- | (In reply to comment #0) | > "E8.0" is an illegal format descriptor, | | Can you cite from the Fortran 95 standard why this is illegal? Good question :-) Unfortunately, I don't have a Fortran 95 reference at hand, and so let me refer to the F77 standard: http://www.fortran.com/fortran/F77_std/rjcnf.html <QUOTE> 13.5.9.2.2 E and D Editing. The Ew.d, Dw.d, and Ew.dEe edit descriptors indicate that the external field occupies w positions, the fractional part of which consists of d digits, unless a scale factor greater than one is in effect, and the exponent part consists of e digits. The e has no effect on input. [. . .] The scale factor k controls the decimal normalization (13.5.7). If -d < k <= 0, the output field contains exactly |k| leading zeros and d - |k| significant digits after the decimal point. If 0 < k < d + 2, the output field contains exactly k significant digits to the left of the decimal point and d - k + 1 significant digits to the right of the decimal point. Other values of k are not permitted. </QUOTE> When d = 0, the only possible value for the scaling factor k is 1. Since "Other values of k are not permitted", you *must* use "1P" with d = 0, as "1PE8.0". Q.E.D. . . . I know this is a rather roundabout logic, and I'm not 100% sure, actually. I'm curious. Now, *if* "E8.0" is legal, what output should be generated for a value of 1e5 ? "0.E5" ? Cheers, Ryo -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35036
