[Numpy-discussion] fromstring doesn't accept buffer object

Nadav Horesh nadavh at visionsense.com
Thu Aug 26 07:07:03 CDT 2004


Sorry for mixing test and production systems: There is no problem here with python 2.3, I got this failure with python 2.4a2:

==========================================
import numarray as n
import Numeric as N

s = '12341234'
b = buffer(s)

print 'numarray: fromstring (string ..) :'
print n.fromstring(s, type=n.Float64)

print 'Numeric: fromstring (string ..) :'
print N.fromstring(s, typecode=N.Float64)

print 'Numeric: fromstring (buffer ..) :'
print N.fromstring(b, typecode=N.Float64)

print 'numarray: fromstring (buffer ..) :'
print n.fromstring(b, type=n.Float64)

=== Results: ====


numarray: fromstring (string ..) :
[  3.05810932e-57]
Numeric: fromstring (string ..) :
[  3.05810932e-57]
Numeric: fromstring (buffer ..) :
[  3.05810932e-57]

=== This error happens only with Python 2.4.a2:

numarray: fromstring (buffer ..) :
Traceback (most recent call last):
  File "test.py", line 17, in ?
    print n.fromstring(b, type=n.Float64)
  File "/usr/local/lib/python2.4/site-packages/numarray/numarraycore.py", line 378, in fromstring
    arr._data, 0, (type.bytes,), type.bytes)
libnumarray.error: copyNbytes: access beyond buffer. offset=7 buffersize=0


  Nadav.

-----Original Message-----
From:	Todd Miller [mailto:jmiller at stsci.edu]
Sent:	Thu 26-Aug-04 15:51
To:	Nadav Horesh
Cc:	numpy-discussion
Subject:	Re: [Numpy-discussion] fromstring doesn't accept buffer object
This is what I see this morning using CVS:

>>> from numarray import *
>>> s = "thisthis"
>>> fromstring(buffer(s), shape=(2,), type=Int32)
array([1936287860, 1936287860])

What kind of failure are you seeing?

Regards,
Todd

On Thu, 2004-08-26 at 09:28, Nadav Horesh wrote:
> Numerc accepts a buffer object instead of a string:
> 
>   arr = Numeric.fromstring(buffer(.some_string), ..)
> while numarray doesn't.
> 
> Is it intentional?
> 
>   Nadav.
> 
> 
> -------------------------------------------------------
> SF.Net email is sponsored by Shop4tech.com-Lowest price on Blank Media
> 100pk Sonic DVD-R 4x for only $29 -100pk Sonic DVD+R for only $33
> Save 50% off Retail on Ink & Toner - Free Shipping and Free Gift.
> http://www.shop4tech.com/z/Inkjet_Cartridges/9_108_r285
> _______________________________________________
> Numpy-discussion mailing list
> Numpy-discussion at lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/numpy-discussion
-- 








More information about the Numpy-discussion mailing list