[Numpy-discussion] Numpy and iterative procedures

Geoffrey Zhu gzhu@peak6....
Thu Feb 15 10:32:32 CST 2007


Thanks Chuck.
 
I am trying to use Successive Over-relaxation to solve linear equations
defined by M*v=3Dq. 
 
There are several goals:
 
1. Eventually (in production) I need it to be fast.
2. I am playing with the guts of the algorithm for now, to see how it
works. that means i need some control for now.
3. Even in production, there is a chance i'd like to have the ability to
tinker with the algorithm. 
 

  _____  

From: numpy-discussion-bounces@scipy.org
[mailto:numpy-discussion-bounces@scipy.org] On Behalf Of Charles R
Harris
Sent: Thursday, February 15, 2007 10:11 AM
To: Discussion of Numerical Python
Subject: Re: [Numpy-discussion] Numpy and iterative procedures





On 2/15/07, Geoffrey Zhu <gzhu@peak6.com> wrote: 

	Hi,
	
	I am new to numpy. I'd like to know if it is possible to code
efficient
	iterative procedures with numpy.
	
	Specifically, I have the following problem.
	
	M is an N*N matrix. Q is a N*1 vector. V is an N*1 vector I am
trying to 
	find iteratively from the initial value V_0. The procedure is
simply to
	calculate
	
	V_{n+1}[i]=3D3D1/M[I,i]*(q[i]-
	(M[i,1]*v_{n+1}[1]+M[I,2]*v_{n+1}[2]+..+M[i,i-1]*v_{n+1}[i-1]) -
	(M[I,i+1]*v_{n}[i+1]+M[I,i+2]*v_{n}[i+2]+..+M[I,N]*v_{n}[N])) 
	
	I do not see that this is something that can esaily be
vectorized, is
	it?


I think it would be better if you stated what the actual problem is. Is
it a differential equation, for instance. That way we can determine what
the problem class is and what algorithms are available to solve it. 

Chuck




_______________________________________________________=0A=
=0A=
The  information in this email or in any file attached=0A=
hereto is intended only for the personal and confiden-=0A=
tial  use  of  the individual or entity to which it is=0A=
addressed and may contain information that is  propri-=0A=
etary  and  confidential.  If you are not the intended=0A=
recipient of this message you are hereby notified that=0A=
any  review, dissemination, distribution or copying of=0A=
this message is strictly prohibited.  This  communica-=0A=
tion  is  for information purposes only and should not=0A=
be regarded as an offer to sell or as  a  solicitation=0A=
of an offer to buy any financial product. Email trans-=0A=
mission cannot be guaranteed to be  secure  or  error-=0A=
free. P6070214=0A=

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://projects.scipy.org/pipermail/numpy-discussion/attachments/20070215/2f979e1e/attachment-0001.html 


More information about the Numpy-discussion mailing list