[Octave-bug-tracker] [bug #64898] Slow zeros

[anonymous]

URL:
  <https://savannah.gnu.org/bugs/?64898>

                 Summary: Slow zeros
                   Group: GNU Octave
               Submitter: None
               Submitted: Wed 15 Nov 2023 06:52:10 PM UTC
                Category: None
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: None
                  Status: None
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
                 Release: 8.3.0
         Discussion Lock: Any
        Operating System: GNU/Linux
           Fixed Release: None
         Planned Release: None


    _______________________________________________________

Follow-up Comments:


-------------------------------------------------------
Date: Wed 15 Nov 2023 06:52:10 PM UTC By: Anonymous
While pondering the slowness of mxCreateNumericArray in #64882, I wondered if
Octave proper suffered the same issue. Yes it does.
*In Octave:*

>> tic;A=zeros(20000);A(1)=1;toc
Elapsed time is 2.16837 seconds.
--verbatim

*In Matlab:*
++verbatim++
>> tic;A=zeros(20000);A(1)=1;toc
Elapsed time is 0.000268 seconds.

A simple calloc in C code with the same size is the same speed as Matlab
whereas malloc + memset is the same speed as Octave.







    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?64898>

_______________________________________________
Message sent via Savannah
https://savannah.gnu.org/