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Beginner
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What does Remark 8291 mean?

Here is the remark:

 remark #8291: Recommended relationship between field width 'W' and the number of fractional digits 'D' in this edit descriptor is 'W>=D+7'

I have used that FORTRAN statement for Years with VAX compilers and all the way through the last Compaq FORTRAN compiler.

I have Intel FORTRAN 2016 update 3 Parallel Studio running within Visual Studio 2013 Shell 

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Black Belt
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On older mainframes, floating point range was often narrower than with today's 64-bit IEEE double precision, and two digits (and a sign) were enough for the exponent. Now, however, you may need five characters for the exponent field (three digits, sign, 'E'), one for the decimal point, one for the sign of the mantissa. That gives us the w >= d+7 rule. You may need one more character for the leading digit of the mantissa, commonly if you specified 1P in your format or specified one of the ES or EE formats.

The remark is just that -- a remark. You can ignore it, or tell the compiler to keep remarks to itself. I find the remark useful when resurrecting old code and fixing it up so that the output results will not be just asterisks.

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This really has nothing to do with floating point range. Rather, it relates to the minimum number of characters above the fraction digits to avoid errors when using E or D format. For example, if you say E10.6, that doesn't leave enough characters for the sign, decimal point, leading digit, exponent letter, exponent sign and exponent digits.

What was the format it complained about? As Tim says, you can ignore this message if you want.

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