[Numpy-discussion] numpy input with genfromttxt()

Bruce Southey bsouthey@gmail....
Fri Jun 3 10:54:42 CDT 2011


On 06/03/2011 10:33 AM, jonasr wrote:
>
>
> Bruce Southey wrote:
>> On 06/03/2011 09:33 AM, jonasr wrote:
>>> thank you very much, works much nicer and faster in comparison to the
>>> script
>>> i wrote and used before  ,
>>> im not that much used to lambda forms but it seems quit usefull in
>>> situations like this
>>>
>>>
>>> Olivier Delalleau-2 wrote:
>>>> Here's an ugly one-liner:
>>>>
>>>> numpy.genfromtxt('data.txt', converters=dict([k, lambda x:
>>>> float(x.replace(',', '.'))] for k in
>>>> range(len(open('data.txt').readline().strip().split()))))
>>>>
>>>> -=- Olivier
>>>>
>>>> 2011/6/3 jgrub<jonas.ruebsam@web.de>
>>>>
>>>>> Hello, im actually try to read in  data with genfromtxt(),
>>>>> i want to read in numbers which are stored in  a textfile like this:
>>>>>
>>>>> 0,000000        0,001221        0,001221        0,000000
>>>>> 1,278076
>>>>>        160,102539
>>>>>
>>>>> 4,000000E-7     0,000000        0,000000        0,002441
>>>>> 1,279297
>>>>>        160,000000
>>>>>
>>>>> 8,000000E-7     -0,001221       0,000000        0,001221
>>>>> 1,279297
>>>>>        159,897461
>>>>>
>>>>> 1,200000E-6     0,000000        0,000000        0,001221
>>>>> 1,279297
>>>>>        160,000000
>>>>>
>>>>> 1,600000E-6     -0,001221       0,000000        0,003662
>>>>> 1,278076
>>>>>        159,897461
>>>>>
>>>>> 2,000000E-6     0,000000        -0,001221       0,003662
>>>>> 1,279297
>>>>>        160,000000
>>>>>
>>>>> my problem is that they are seperated with a comma so when i try to
>>>>> read
>>>>> them
>>>>> i just get a numpy array with NaN's.  is there a short way to replace
>>>>> the
>>>>> "," with "."  ?
>>>>>
>>>>> --
>>>>> View this message in context:
>>>>> http://old.nabble.com/numpy-input-with-genfromttxt%28%29-tp31757790p31757790.html
>>>>> Sent from the Numpy-discussion mailing list archive at Nabble.com.
>>>>>
>>>>> _______________________________________________
>>>>> NumPy-Discussion mailing list
>>>>> NumPy-Discussion@scipy.org
>>>>> http://mail.scipy.org/mailman/listinfo/numpy-discussion
>>>>>
>>>> _______________________________________________
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>>>>
>> Isn't this just because of the 'locale' settings?
>> A quick search showed  ticket 884 that has code changing the locale that
>> may be useful for you:
>> http://projects.scipy.org/numpy/ticket/884
>>
>> Perhaps a similar bug exists with genfromtxt?
>>
>> If it is nicely behaved, just use Python's csv module.
>>   From the csv documentation:
>> "Since open()
>> <http://docs.python.org/release/3.1.3/library/functions.html#open>  is
>> used to open a CSV file for reading, the file will by default be decoded
>> into unicode using the system default encoding (see
>> locale.getpreferredencoding()
>> <http://docs.python.org/release/3.1.3/library/locale.html#locale.getpreferredencoding>).
>> To decode a file using a different encoding, use the encoding argument
>> of open:"
>>
>>
>> Bruce
>>
>>
>>
>> _______________________________________________
>> NumPy-Discussion mailing list
>> NumPy-Discussion@scipy.org
>> http://mail.scipy.org/mailman/listinfo/numpy-discussion
>>
>>
> i checked my local settings and got
>
> In [37]: locale.getlocale()
> Out[37]: ('de_DE', 'UTF8')
>
> when i try
>
> locale.setlocale(locale.LC_NUMERIC, 'de_DE')
>
> i get: Error: unsupported locale setting
> same with 'fi_FI'
> any idea ?
>
>
>
>
You don't seem to be using Python.
The 'In [37]' suggest ipython so you have to find how ipython does this.

However, I am not sure that changing locale will help here but I am 
rather naive on this. If it doesn't then file a ticket with a clear 
example and ideally with a patch (one can hope).

Bruce



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