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Bill Dandreta | 1 Dec 2005 07:06
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Re: (OT) Grouping of data points.

Stephen Walton wrote:

>You need graph theory.  I just did a similar project (in MATLAB, but 
>anyway) having to do with sunspots.  I needed to put sunspots into 
>groups by finding sunspots which were "close" in latitude and 
>longitude.  The eventual algorithm looked like this:
>
>1.  For each point i, compute its distance from point j.  (This part of 
>the algorithm is n**2, unfortunately.)  Set A[i,j] and A[j,i] to 1 if 
>the distance is less than some value, and 0 if it is greater.  A is in 
>fact an adjacency graph in MATLAB-ese, where A[i,j] is nonzero if vertex 
>i of a graph is connected to vertex j by an edge.  "Distance" here can 
>have any definition of course;  it doesn't have to be Cartesian.
>
>2. Find the components in the resulting graph, defined as those sets of 
>vertices which are in fact connected.  The algorithm for doing this is 
>at http://www.ececs.uc.edu/~gpurdy/lec20.html, in section 20.2.
>
>I also recommend the graph theory tutorial at 
>http://www.utm.edu/departments/math/graph.
>
Thanks Stephen, It looks like graph theory might fit the bill. The links 
look interesting but are over my head right now. It will take some 
studying for me to come up to speed.

Bill
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Chris Fonnesbeck | 1 Dec 2005 20:53
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strange scipy.f2py error

For some reason, the fcompiler object gets set to "None" when building
on a 10.3 machine. Using today's svn build of scipy_core and the IBM
XLF compiler:

compiling Fortran sources
Traceback (most recent call last):
  File "setup.py", line 17, in ?
    ext_modules = [flib]
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/scipy/distutils/core.py",
line 91, in setup
    return old_setup(**new_attr)
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/distutils/core.py",
line 149, in setup
    dist.run_commands()
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/distutils/dist.py",
line 946, in run_commands
    self.run_command(cmd)
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/distutils/dist.py",
line 966, in run_command
    cmd_obj.run()
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/distutils/command/build.py",
line 112, in run
    self.run_command(cmd_name)
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/distutils/cmd.py",
line 333, in run_command
    self.distribution.run_command(command)
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/distutils/dist.py",
line 966, in run_command
    cmd_obj.run()
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/scipy/distutils/command/build_ext.py",
(Continue reading)

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George Nurser | 2 Dec 2005 01:38
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fortran compilers, f2py and scipy core.

This may be a stupid question, but ...  I want to use f2py together  
with scipy core, and new scipy, on an Opteron.

I am used to writing my fortran programs with ifort 9.0. Does this  
mean that I have to compile scipy, scipy core with ifort, or can a  
scipy core compiled with gcc coexist with fortran routines, compiled  
on ifort 9.0, linked into f2py?

Problem is there don't seem to be options set for 64-bit emt ifort in  
scipy/distutils/fcompiler/

--George Nurser.
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Dave Kuhlman | 2 Dec 2005 02:27

Version 0.3.2 or 0.4.3?


At www.scipy.org I find SciPy_complete-0.3.2.tar.gz.

At http://sourceforge.net/projects/scipy/, I find
scipy-0.4.3.tar.gz.

Are these two separate projects?  They seem very different.

Could someone tell me where I can find a description of the
difference between these two and a guide on how I determine which
I should be using.

I'm sure this question must have been raised before, but I did
some searching at www.scipy.org and in the FAQ and in the
mail-list archives and could not find anything helpful.

Thanks in advance for help.

Dave

--

-- 
Dave Kuhlman
http://www.rexx.com/~dkuhlman
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Ryan Krauss | 2 Dec 2005 02:58
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Re: Version 0.3.2 or 0.4.3?

They are the same and yet different.  0.4.3 is "new scipy".  You will
find more on the list if you look for information about new scipy. 
You will probably get a more detailed answer from some one else later,
but the biggest difference is that "old scipy" - i.e. <=0.3.2 depends
on Numeric and/or numarray for matrices and arrays.  Travis Oliphant
has redesigned the matrix/array API for "new scipy".  You can read
about why he did this in the first chapter of a book he has written
about new scipy.  The first two chapters can be downloaded for free
with a link on this page:
http://www.tramy.us/guidetoscipy.html

I don't have a good feel for how stable new scipy is and how many
people are using it for their everyday work.  I am actually using old
scipy still myself.

Ryan

On 12/1/05, Dave Kuhlman <dkuhlman <at> cutter.rexx.com> wrote:
>
> At www.scipy.org I find SciPy_complete-0.3.2.tar.gz.
>
> At http://sourceforge.net/projects/scipy/, I find
> scipy-0.4.3.tar.gz.
>
> Are these two separate projects?  They seem very different.
>
> Could someone tell me where I can find a description of the
> difference between these two and a guide on how I determine which
> I should be using.
>
(Continue reading)

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Martin Kuemmel | 2 Dec 2005 08:03
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AstroAsciiData: first release!

Dear all,

this email is the announcement of
the first release of the Python module

AstroAsciiData.

With this module it is possible to:
* read ASCII tables;
* access its elements for reading and writing;
* save the ASCII table back to a file;
* delete/add rows and columns;
* convert columns to numarrays.

To get a first impression on what this module does
and how it works, please check the example below.
More information, and of course the software
itself and the manual, is available on the
project webpages at:
http://www.stecf.org/software/astroasciidata/

The software was developed as a contribution to the
AstroLib project. Any kind of feedback can be
posted on the AstroAsciiData wiki at

http://www.scipy.org/wikis/topical_software/AstroAsciiData

or sent by email to AstroAsciiData <at> stecf.org

Please check on the webpage if the module could be
(Continue reading)

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Ed Schofield | 2 Dec 2005 11:39
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Re: Version 0.3.2 or 0.4.3?

On 02/12/2005, at 1:27 AM, Dave Kuhlman wrote:
>
> At www.scipy.org I find SciPy_complete-0.3.2.tar.gz.
>
> At http://sourceforge.net/projects/scipy/, I find
> scipy-0.4.3.tar.gz.
>
> Are these two separate projects?  They seem very different.
>
> Could someone tell me where I can find a description of the
> difference between these two and a guide on how I determine which
> I should be using.

Hi Dave,

I suggest you use the new scipy, version 0.4.3.  The new scipy is  
already stable enough that 1360+ unit tests pass (usually all).  It's  
also being continuously improved, so if you post any questions here  
you are likely to get a very fast response.  Development of the old  
version has ceased.

The procedure is to install scipy_core (from http:// 
numeric.scipy.org/), then scipy.

Good luck,
-- Ed
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Travis Oliphant | 2 Dec 2005 16:50
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Re: [SciPy-dev] PyArray_New problem

Robert Cimrman wrote:

>Could someone tell me what I am doing wrong? I would like to use a 
>function like the snippet below to create an array.
>
>PyArrayObject *helper_newCArrayObject_i32( int32 len, int32 *array ) {
>   intp plen[1];
>   PyArrayObject *obj = 0;
>
>   plen[0] = len;
>   printf( "11111 %d\n", PyArray_INT32 );
>/*   obj = (PyArrayObject *) PyArray_SimpleNew( 1, plen, PyArray_INT32 ); */
>
>   obj = (PyArrayObject *) PyArray_New( &PyArray_Type, 1, plen, 
>PyArray_INT32, NULL, NULL, 0, CARRAY_FLAGS, NULL );
>....
>  
>

First of all, don't pass in CARRAY_FLAGS when the data argument to 
PyArray_New is NULL.  A non-zero flags entry tells the subroutine to 
create a FORTRAN strides array if no data is passed.

Remember:  DATA flags are only to describe already available memory.   
If you create the memory  in PyArray_New, then the only thing to decide 
is FORTRAN or C- contiguous.   So, in this routine, you are creating a 
Fortran array.  Perhaps this is causing problems later.

Also, you are not showing us the rest of the code.  Your traceback is 
showing PyArray_ValidType being called which is not shown anywere...
(Continue reading)

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José María | 2 Dec 2005 16:57
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[Scipy installation] No admin account

My name is José María and this is my first post here.

I have started this week learning both: python and scipy. I had no problem to 
install Scipy at windows and linux in my computer.

I would like to use Scipy at work where we use windows 2000. The installation 
software tells me than i can't install Scipy because I don't have enough 
privilegies.

There exist any alternative to install Scipy without an administrative 
account?

Best regards from Spain (sorry my english, please),
José María
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Sven Schreiber | 2 Dec 2005 17:53
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how to get matplotlib working with new scipy?

Dear experienced scipy users,

I apologize if this is not the best/correct list to ask, but I joined only recently and so here goes:
I'd like to try matplotlib, and I have the new scipy (core & rest) installed on win32. After
installation, the command "from pylab import *" fails with the message "ImportError: No module named
Numeric". That's not too surprising, but I'm unsure about the best strategy to pursue.

Is matplotlib supposed to work with new scipy (alone, without extra numeric or numarray)? If so, how
do I have to set it up?

If numeric or numarray is still needed, is there any danger of "double definitions" of arrays etc.,
such that scripts could get confused or, worse, produce wrong results? (In theory I guess everything
should be fine, but I'd be glad to hear what's the actual status quo with respect to known bugs and
such.)

Thanks much for your help,
Sven
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Gmane