From: Sam S. <sd...@gn...> - 2004-04-30 15:36:08
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Bruno, I think this is a bug: [20]> (LOG -3/4) WARNING: Numerical operation combines exact and inexact numbers (rational numbers and floating-point numbers), and the mathematical result is exact. See ANSI CL 12.1.4.1 and the CLISP impnotes for details. The result's actual exactness is controlled by *FLOATING-POINT-RATIONAL-CONTAGION-ANSI*. To shut off this warning, set *WARN-ON-FLOATING-POINT-RATIONAL-CONTAGION* to NIL. #C(-0.2876821 3.1415927) Could you please fix it? (together with a similar bug [24]> (cosh #c(1d0 2d0)) WARNING: Floating point operation combines numbers of different precision. See ANSI CL 12.1.4.4 and the CLISP impnotes for details. The result's actual precision is controlled by *FLOATING-POINT-CONTAGION-ANSI*. To shut off this warning, set *WARN-ON-FLOATING-POINT-CONTAGION* to NIL. WARNING: Floating point operation combines numbers of different precision. See ANSI CL 12.1.4.4 and the CLISP impnotes for details. The result's actual precision is controlled by *FLOATING-POINT-CONTAGION-ANSI*. To shut off this warning, set *WARN-ON-FLOATING-POINT-CONTAGION* to NIL. #C(-0.64214812471552d0 1.0686074213827783d0) which would require either eliminating one of lf_len_extend and lf_len_extend1 or disabling the warning for intermediate operations) -- Sam Steingold (http://www.podval.org/~sds) running w2k <http://www.camera.org> <http://www.iris.org.il> <http://www.memri.org/> <http://www.mideasttruth.com/> <http://www.honestreporting.com> If you want it done right, you have to do it yourself |
From: Bruno H. <br...@cl...> - 2004-04-30 16:53:19
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Sam wrote: > Could you please fix it? Put it into the bug tracker on SF if you don't want to fix it. I'm busy with CLOS now. > which would require either eliminating one of lf_len_extend and > lf_len_extend1 Then the transcendental functions would not yield precise results any more! Not acceptable. > disabling the warning for intermediate operations) Hide the problems under the carpet?? The warnings show that the results would differ between ANSI and non-ANSI mode. I don't want (cosh #c(1d0 2d0)) to return different results in the two modes, or spend time with useless computations in one mode but not in the other. I think the fix is to insert R_F_float_F calls at the appropriate places, to reduce the precision at those places where clisp in traditional mode does it by default but clisp in ansi mode doesn't do it. Bruno |
From: Sam S. <sd...@gn...> - 2004-04-30 17:38:27
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> * Bruno Haible <oe...@py...t> [2004-04-30 18:45:38 +0200]: > > Sam wrote: >> Could you please fix it? > > Put it into the bug tracker on SF if you don't want to fix it. I'm > busy with CLOS now. OK. >> disabling the warning for intermediate operations) > > The warnings show that the results would differ between ANSI and > non-ANSI mode. no. they show that clisp uses different precision for different computations and does not sync the precision when it combines the results. > I think the fix is to insert R_F_float_F calls at the appropriate > places, to reduce the precision at those places where clisp in > traditional mode does it by default but clisp in ansi mode doesn't do > it. precisely. -- Sam Steingold (http://www.podval.org/~sds) running w2k <http://www.camera.org> <http://www.iris.org.il> <http://www.memri.org/> <http://www.mideasttruth.com/> <http://www.honestreporting.com> The only intuitive interface is the nipple. The rest has to be learned. |