On Tue, Feb 10, 2009 at 9:40 PM, A B <python6009@gmail.com> wrote:

Hi,

How do I write a loadtxt command to read in the following file and store each data point as the appropriate data type:

12|h|34.5|44.5 14552|bbb|34.5|42.5

Do the strings have to be read in separately from the numbers?

Why would anyone use 'S10' instead of 'string'?

dt = {'names': ('gender','age','weight','bal'), 'formats': ('i4', 'S4','f4', 'f4')}

a = loadtxt("sample_data.txt", dtype=dt)

gives

ValueError: need more than 1 value to unpack

I can do a = loadtxt("sample_data.txt", dtype="string") but can't use 'string' instead of S4 and all my data is read into strings.

Seems like all the examples on-line use either numeric or textual input, but not both.

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works for me but not sure i understand the problem, did you try setting the delimiter? import numpy as np from cStringIO import StringIO txt = StringIO("""\ 12|h|34.5|44.5 14552|bbb|34.5|42.5""") dt = {'names': ('gender','age','weight','bal'), 'formats': ('i4', 'S4','f4', 'f4')} a = np.loadtxt(txt, dtype=dt, delimiter="|") print a.dtype

On 2/11/2009 6:40 AM, A B wrote:

Hi,

How do I write a loadtxt command to read in the following file and store each data point as the appropriate data type:

12|h|34.5|44.5 14552|bbb|34.5|42.5

dt = {'names': ('gender','age','weight','bal'), 'formats': ('i4', 'S4','f4', 'f4')}

Does this work for you? dt = {'names': ('gender','age','weight','bal'), 'formats': ('i4','S4','f4', 'f4')} with open('filename.txt', 'rt') as file: linelst = [line.strip('\n').split('|') for line in file] n = len(linelst) data = numpy.zeros(n, dtype=numpy.dtype(dt)) for i,(gender, age, weight, bal) in zip(range(n),linelst): data[i] = (int(gender), age, float(weight), float(bal)) S.M.