bugGNU Octave - Bugs: bug #53463, nextpow2 with Inf or NaN arguments


bug #53463: nextpow2 with Inf or NaN arguments

Submitter:  Dildar Sk <hodor123456>
Submitted:  Sun 25 Mar 2018 02:54:30 PM UTC
Category:  Octave Function Severity:  3 - Normal
Priority:  5 - Normal Item Group:  Matlab Compatibility
Status:  Fixed Assigned to:  None
Originator Name:  Dildar Sk Open/Closed:  * Closed
Release:  * dev Operating System:  * GNU/Linux
Fixed Release:  None Planned Release:  None
* Mandatory Fields

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Thu 12 Apr 2018 09:36:24 PM UTC, comment #2: 

I fixed this bug using a slightly different strategy.  When the two-input form of the log2 function fails, the exponent returned is 0.  I can use that fact to identify the input values like Inf or NaN that need special processing.

I added new BIST tests to check that this all works.  See this changeset (http://hg.savannah.gnu.org/hgweb/octave/rev/69b21b8a0e9f).

Marking as fixed and closing report.

Rik <rik5>
Group administrator
Sun 25 Mar 2018 02:59:47 PM UTC, comment #1: 

I added the referred two cases in that function.
Added a test also.
patch attached.

(file #43670)

Dildar Sk <hodor123456>
Sun 25 Mar 2018 02:54:30 PM UTC, original submission:  


>> nextpow2(inf)

ans =


>> nextpow2(NaN)

ans =



In GNU Octave,

>> nextpow2(inf)
ans = 0
>> nextpow2(NaN)
ans = 0

So,here Octave neither producing valid answer nor warning.

Dildar Sk <hodor123456>


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Attach Files:

Attached Files
file #43670:  nextpow2.patch added by hodor123456 (843B - text/x-patch)


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  • -email is unavailable- added by rik5 (Posted a comment)
  • -email is unavailable- added by mtmiller (Updated the item)
  • -email is unavailable- added by hodor123456 (Submitted the item)
  • -email is unavailable- added by hodor123456

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    Follow 7 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2018-04-12 rik5 StatusPatch Submitted Fixed
        Open/ClosedOpen Closed
    2018-03-27 mtmiller Item GroupIncorrect Result Matlab Compatibility
        StatusNone Patch Submitted
        Summarynextpow2: Should produce correct result or error nextpow2 with Inf or NaN arguments
    2018-03-25 hodor123456 Attached File- Added nextpow2.patch, #43670
    2018-03-25 hodor123456 Carbon-Copy- Added -email is unavailable-

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