December 2006 - ieee-floats-devel@lists.common-lisp.net

[Ieee-floats-devel] Re: underflows, overflows
by Marijn Haverbeke 14 Dec '06

14 Dec '06

Hey, If you download the code again you should find your problem gone. I hadn't realized exponents of 0 are not just used for encoding 0, but also for small numbers. I removed the underflow test and just return 0 for really tiny numbers -- not sure if this is always proper, but it seems to be a common approach. Regards, Marijn

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[Ieee-floats-devel] underflows, overflows
by Alexey Goldin 14 Dec '06

14 Dec '06

I was quite excited to see your project --- recently I needed something like this and even wrote similar utils. Unfortunately I believe your code suffers from incorrectly interpreting underflows and overflows. For example: (format t "~b" (parse-integer "47" :radix 16)) 1000111 NIL CL-USER> IEEE-FLOATS> (encode-float32 9.9492191e-44) ; Evaluation aborted IEEE-FLOATS> (decode-float32 #b1000111) 5.0446745e-44 IEEE-FLOATS> According to http://babbage.cs.qc.edu/IEEE-754/ this binary pattern is more like 9.9492191e-44 Attached is my code with tests. It is uglier then yours and does not handle nan, infinity, etc. May be you can incorporate changes, I then should be able to wipe mine code and just use yours. If not, I'll be able to send you patches in few days. Thanks!

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[Ieee-floats-devel] Auto-nag: ieee-floats please update your webpage
by root＠common-lisp.net 11 Dec '06

11 Dec '06

You are being nagged on because you have not created a sensible default webpage for your project. Please do so or you will be nagged again next week. All we ask is that you type in something about the project and perhaps some links to mailinglists etc. See common-lisp.net/project/clo/sp/index.html for a reasonable template. Some projects host their webpages somewhere else (eg. http://common-lisp.net/project/cl-ppcre) and if you're in the same situation you may put the following in your index.shtml: <HTML> <HEAD> <META HTTP-EQUIV="refresh" CONTENT="0;URL=YOURURLGOESHERE"> </HEAD> <BODY> </BODY> </HTML> Any questions? You can reach the author of this cronjob at clo-devel(a)common-lisp.net Thanks!

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