From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] double->string conversion
From: rog@vitanuova.com
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Message-Id: <20011029135247.B5F69199E8@mail.cse.psu.edu>
Date: Mon, 29 Oct 2001 14:05:49 +0000
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> doesn't print("%g") do it?

nope. for example, 

	double xmin, xmax;
	[...]
	print("%g %g; difference: %g\n", xmin, xmax, xmax - xmin);
	print("hex: %ullx %ullx\n", *(vlong *)&xmin, *(vlong *)&xmax);

prints:

	-.9909985 -.9909985 difference: 4.551914e-15
	hex: bfefb6429008c02c bfefb6429008c003

> The %f, %g, strtod functions in both Inferno and 3rd edition Plan 9
> are intended to be accurate.   (The version in 2nd edition is known
> to be less exact.)

what parameters does the %g conversion need to ensure
that a later strtod will produce the same value?

  rog.