numpy.distutils seems to have difficulties detecting the current version of the
g95 compiler. I believe this is because the output of `g95 --version` has
changed. The patch below seems to correct the problem (i.e. it now works with
the latest g95) but my regexp foo is very weak so it may not be correct/optimal.
--- /usr/lib64/python2.3/site-packages/numpy/distutils/fcompiler/g95.py
2006-01-06 21:29:40.000000000 +0000
+++ /home/jgraham/lib64/python/numpy/distutils/fcompiler/g95.py 2006-05-26
12:49:50.000000000 +0100
@@ -9,7 +9,7 @@
class G95FCompiler(FCompiler):
compiler_type = 'g95'
- version_pattern = r'G95.*\(experimental\) \(g95!\) (?P<version>.*)\).*'
+ version_pattern = r'G95.*(?:\(experimental\))? \(g95!\) (?P<version>.*)\).*'
executables = {
'version_cmd' : ["g95", "--version"],
--
"You see stars that clear have been dead for years
But the idea just lives on..." -- Bright Eyes
At 08:10 PM 5/30/2006, you wrote:
>1) Have you transitioned or started to transition to NumPy (i.e. import
>numpy)?
only by following the threads here, so far
no download yet
>2) Will you transition within the next 6 months? (if you answered No to #1)
yes, on this next project (assuming the small array, <2048,
performance compares to Numeric
>3) Please, explain your reason(s) for not making the switch. (if you
>answered No to #2)
if no, it is because most projects involve small bin number FFTs and
correlations
>4) Please provide any suggestions for improving NumPy.
24 bit signed integer type, for the new class of ADCs coming out (or
at least the ability to cast efficiently to Float32)
a GPU back-end option for FFT ;-)
Thanks, it's all good,
Ray
Consider these two operations:
>>> a=numpy.empty( 1024 )
>>> b=numpy.empty( 1024 )
>>> a[1:] = b[:-1]
>>> a[1:] = a[:-1]
>>>
It seems that in the second operation
we need to copy the view a[:-1]
but in the first operation we don't need
to copy b[:-1].
How does numpy detect this, or does it
always copy the source when assigning to a slice ?
I've poked around the (numpy) code a bit and
tried some benchmarks, but it's still not so
clear to me.
Simon.
--
Simon Burton, B.Sc.
Licensed PO Box 8066
ANU Canberra 2601
Australia
Ph. 61 02 6249 6940
http://arrowtheory.com
Is it possible to create arrays that run from, say -5:5, rather than
0:11? Analogous to the Fortran "allocate(A(-5:5))" command? I'm
translating a F90 code to Python, and it would be easier to do this
than to use a python dictionary.
Thanks in advance.
Rick Muller
rmuller(a)sandia.gov
>Is there some clever way to achieve the same goal for 24bit data without
>copying everything into a new 32-bit array?
I agree with the other post, Int8 x 3 can be used with slices to get a lot done, depending on data tasks desired, but not all
>The typical 24bit audio file contains two interleaved channels, i.e.
>frames of 3bytes+3bytes, so it can be cast to (nframes,3) Int32, or
>(nframes,2,3) Int8 array, but this is hardly a useful representation for
>audio data.
Along these liners, I have been working with 24 bit ADC data returned from pyUSB as tuples, which I need to convert to Float32 and save, like this:
WRAP = 2.**23
BITS24 = 2.**24
try:
chValue = struct.unpack(">I",
struct.pack(">4b", 0,*dataTuple[byteN:byteN+3])
)[0]
except:
chValue = 0
if chValue>WRAP:
chValue = ((BITS24-chValue) / WRAP) * gainFactors[thisCh]
else:
chValue = (-chValue / WRAP) * gainFactors[thisCh]
data[thisCh].append(chValue)
which is really slow (no real time is possible).
Is there a much faster way evident to others here?
We are going to do a pyd in C otherwise...
Ray
Please disregard my previous posting about my special issue correspondence.
All is well. Gmail and my twitching don't work well together. I need a
computer that ignores me.
In April I sent out a request for proposals for a special issue of Computing
in Science and Engineering on Python's use in science and engineering. Due
to being somewhat inexperienced with a new mailer, I lost some of the
correspondence. Would those with whom I corresponded send me back something
about what we were talking about? I know some additional people had gotten
dragged into the conversation.
I did not lose letters from:
Jarrod Millman
Kent-Andre Mardal
Xuan Shi
Ryan Krauss
I have the word doc only from Peter Bienstman.
I have the text outline only from Arnd Baecker
Sorry to be so clumsy.
Paul Dubois
Hi all.
I'm writing a tool to access uncompressed audio files (currently in
wave, aiff and wave64 formats) using numarray.memmap module -- it maps
the whole file to memory, then finds the waveform data region and casts
it to and array of appropriate type and shape.
This works pretty well for both 16-bit integer and 32-bit float data,
but not for 24-bit files, since there is no Int24 data type in numarray.
Is there some clever way to achieve the same goal for 24bit data without
copying everything into a new 32-bit array?
The typical 24bit audio file contains two interleaved channels, i.e.
frames of 3bytes+3bytes, so it can be cast to (nframes,3) Int32, or
(nframes,2,3) Int8 array, but this is hardly a useful representation for
audio data.
--Maxim
