[NumPy-Tickets] [NumPy] #1616: numpy.loadtxt uses both file-like and iterator interfaces instead of just one

[NumPy Trac]

#1616: numpy.loadtxt uses both file-like and iterator interfaces instead of just
one
-------------------------+--------------------------------------------------
 Reporter:  zachrahan    |       Owner:  somebody    
     Type:  enhancement  |      Status:  needs_review
 Priority:  normal       |   Milestone:  1.5.1       
Component:  Other        |     Version:  devel       
 Keywords:               |  
-------------------------+--------------------------------------------------
Changes (by derek):

  * status:  new => needs_review


Comment:

 Duh, WikiFormatting! Meant of course
 {{{
 BytesIO.__next__()
 }}}
 That makes it

 {{{
 diff --git a/numpy/lib/npyio.py b/numpy/lib/npyio.py
 index 9fbacaa..f236006 100644
 --- a/numpy/lib/npyio.py
 +++ b/numpy/lib/npyio.py
 @@ -679,7 +679,10 @@ def loadtxt(fname, dtype=float, comments='#',
 delimiter=None,
      elif hasattr(fname, 'readline'):
          fh = fname
      else:
 -        raise ValueError('fname must be a string or file handle')
 +        try:
 +            fh = iter(fname)
 +        except:
 +            raise ValueError('fname must be a string or file handle')
      X = []

      def flatten_dtype(dt):
 @@ -737,14 +740,18 @@ def loadtxt(fname, dtype=float, comments='#',
 delimiter=None,

          # Skip the first `skiprows` lines
          for i in xrange(skiprows):
 -            fh.readline()
 +            try:
 +                next(fh)
 +            except StopIteration:
 +                raise IOError('End-of-file reached before encountering
 data.')

          # Read until we find a line with some values, and use
          # it to estimate the number of columns, N.
          first_vals = None
          while not first_vals:
 -            first_line = fh.readline()
 -            if not first_line: # EOF reached
 +            try:
 +                first_line = next(fh)
 +            except StopIteration:      # EOF reached
                  raise IOError('End-of-file reached before encountering
 data.')
              first_vals = split_line(first_line)
          N = len(usecols or first_vals)
 }}}

-- 
Ticket URL: <http://projects.scipy.org/numpy/ticket/1616#comment:2>
NumPy <http://projects.scipy.org/numpy>
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