You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@commons.apache.org by "Thomas Neidhart (Issue Comment Edited) (JIRA)" <ji...@apache.org> on 2012/02/13 14:30:59 UTC

[jira] [Issue Comment Edited] (MATH-745) up to 5x Performance Improvement on FasFourierTransformer.java by using a recursive iterative sumation Approach

    [ https://issues.apache.org/jira/browse/MATH-745?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13206867#comment-13206867 ] 

Thomas Neidhart edited comment on MATH-745 at 2/13/12 1:30 PM:
---------------------------------------------------------------

I was curious to see if a recursion is really faster than a loop. The test results can be seen here:
{noformat} 
fft (calls per timed block: 1000, timed blocks: 100, time unit: ms)
     name      time/call      std error total time      ratio      difference
     Loop 6.97587976e-02 1.15353985e-02 6.9759e+03 1.0000e+00  0.00000000e+00
Recursive 7.11088946e-02 5.04734785e-03 7.1109e+03 1.0194e+00  1.35009693e+02
{noformat} 
The function being transformed is a simple sin.
                
      was (Author: tn):
    I was curious to see if a recursion is really faster than a loop. The test results can be seen here:

fft (calls per timed block: 1000, timed blocks: 100, time unit: ms)
     name      time/call      std error total time      ratio      difference
     Loop 6.97587976e-02 1.15353985e-02 6.9759e+03 1.0000e+00  0.00000000e+00
Recursive 7.11088946e-02 5.04734785e-03 7.1109e+03 1.0194e+00  1.35009693e+02

The function being transformed is a simple sin.
                  
> up to 5x Performance Improvement on FasFourierTransformer.java by using a recursive iterative sumation Approach
> ---------------------------------------------------------------------------------------------------------------
>
>                 Key: MATH-745
>                 URL: https://issues.apache.org/jira/browse/MATH-745
>             Project: Commons Math
>          Issue Type: Improvement
>    Affects Versions: 3.0
>            Reporter: Leandro Ariel Pezzente
>              Labels: FFT, Fast, Fourier, Transform
>         Attachments: FastFourierTransformer.patch.txt
>
>
> By swithinch form a loop iterative approach to a recursive iterative approach on fastFourierTransformer.java a Perfomance Improvement of up to 5x is gained.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira