Thanks!

I'll get to work!



"Microsoft isn't evil, they just make really crappy operating systems." 
-Linus Torvalds



[EMAIL PROTECTED] wrote:
> Send Tutor mailing list submissions to
>       [email protected]
>
> To subscribe or unsubscribe via the World Wide Web, visit
>       http://mail.python.org/mailman/listinfo/tutor
> or, via email, send a message with subject or body 'help' to
>       [EMAIL PROTECTED]
>
> You can reach the person managing the list at
>       [EMAIL PROTECTED]
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Tutor digest..."
>
>
> Today's Topics:
>
>    1. matrix-vector multiplication errors (Dinesh B Vadhia)
>    2. Where to start? (William Kilmartin)
>    3. Re: Where to start? (Alan Gauld)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Fri, 1 Feb 2008 14:13:00 -0800
> From: "Dinesh B Vadhia" <[EMAIL PROTECTED]>
> Subject: [Tutor] matrix-vector multiplication errors
> To: <[email protected]>
> Message-ID: <[EMAIL PROTECTED]>
> Content-Type: text/plain; charset="iso-8859-1"
>
> I've posted this on the Scipy forum but maybe there are answers on Tutor too. 
>  I'm performing a standard Scipy matrix* vector multiplication, b=Ax , (but 
> not using the sparse module) with different sizes of A as follows:  
>
>
> Assuming 8 bytes per float, then:
> 1. matrix A with M=10,000 and N=15,000 is of approximate size: 1.2Gb
> 2. matrix A with M=10,000 and N=5,000 is of approximate size: 390Mb
> 3. matrix A with M=10,000 and N=1,000 is of approximate size: 78Mb
>
> The Python/Scipy matrix initialization statements are:
>   
>> A = scipy.asmatrix(scipy.empty((I,J), dtype=int))
>> x = scipy.asmatrix(scipy.empty((J,1), dtype=float))
>> b = scipy.asmatrix(scipy.empty((I,1), dtype=float))
>>     
>
> I'm using a Windows XP SP2 PC with 2Gb RAM.
>
> Both matrices 1. and 2. fail with INDeterminate values in b.  Matrix 3. works 
> perfectly.  As I have 2Gb of RAM why are matrices 1. and 2. failing?
>
> The odd thing is that Python doesn't return any error messages with 1. and 2. 
> but we know the results are garbage (literally!)
>
> Cheers!
>
> Dinesh
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: 
> http://mail.python.org/pipermail/tutor/attachments/20080201/5c3abb34/attachment-0001.htm
>  
>
> ------------------------------
>
> Message: 2
> Date: Fri, 01 Feb 2008 20:52:39 -0800
> From: William Kilmartin <[EMAIL PROTECTED]>
> Subject: [Tutor] Where to start?
> To: [email protected]
> Message-ID: <[EMAIL PROTECTED]>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Here's what I'm trying to accomplish;
>
> I track statistics at work.  E.g. calls out, $ collected etc..
>
> The graph has a rough guess of highest possible at the top and the 
> lowest number in the past 3 months at the bottom.
>
> It's a simple line graph, week after week.
>
> I need to be able to add names of various statistics.  I.e. calls out, 
> money collected, proposals sent etc..
>
> It then needs to create the graph, store the names, be able to take the 
> week's numbers and store them along with being able to print.  The 
> highest and lowest points also need to also be inputed and changed if 
> needed.
>
> Ideally this would be a GUI driven app for the sake of simplicity.
>
> What I'm looking for is advice on where to start, a middle ground and an 
> end.  I'm new to Python and programming and took this as the 1st thing 
> I'd to create. 
>
> I've been studying for a bit now and knowing where I'm going would be 
> very helpful.
>
>
>   
_______________________________________________
Tutor maillist  -  [email protected]
http://mail.python.org/mailman/listinfo/tutor

Reply via email to