Initial- and boundary-value problems in Maxima.



Richard Fateman wrote:


>> I have here the profiling we did using sbcl.  One of the routines which
>> is most used and takes time is COLNEW::DAXPY
> DAXPY is a fundamental part of LINPACK, I think.  

Yes

> unfortunately, if I understand the SBCL profiling, the time spent in the
> 28 calls DAXPY constitutes less than 1% of the time for the whole task.

There are indirect calls to daxpy, in fact 1164244, even if few samples fall 
inside because it is a so small function, and ther eare not a lot of samples
generally.


> 
> the other colnew functions, approx  and vwblok  are also insignificant
> (less than 1%).
> 
> The profile reveals that SIMPLIFYA and its subroutines take 20.5% of the
> time.
> If you know that all the variables are floats, then SIMPLIFYA should be
> largely
> removed by mode_declare and compiling.
> 

Ordinary profiling shows that approx, vwblock etc. eat half of the time.


  seconds  |     gc     |     consed    |  calls |  sec/call  |  name                            
------------------------------------------------------------                                     
    31.360 |      0.928 |   836,818,968 |  1,064 |   0.029473 | 
COLNEW::LSYSLV                   
    16.420 |      0.225 |   349,003,072 | 23,178 |   0.000708 | 
COLNEW::VWBLOK                   
     9.829 |      0.937 |   800,942,728 | 52,124 |   0.000189 | 
COLNEW::DGESL                    
     4.254 |      0.481 |   318,090,424 |  7,726 |   0.000551 | 
COLNEW::DGEFA                    
------------------------------------------------------------                                     
    61.862 |      2.571 | 2,304,855,192 | 84,092 |            | Total                            
                                                      



-- 
Michel Talon