diff options
Diffstat (limited to 'numpy/lib/npyio.py')
| -rw-r--r-- | numpy/lib/npyio.py | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/numpy/lib/npyio.py b/numpy/lib/npyio.py index a40de4fea..c8cebaed8 100644 --- a/numpy/lib/npyio.py +++ b/numpy/lib/npyio.py @@ -1204,7 +1204,8 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None, usecols=None, names=None, excludelist=None, deletechars=None, replace_space='_', autostrip=False, case_sensitive=True, defaultfmt="f%i", - unpack=None, usemask=False, loose=True, invalid_raise=True): + unpack=None, usemask=False, loose=True, invalid_raise=True, + nrows=None): """ Load data from a text file, with missing values handled as specified. @@ -1285,6 +1286,11 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None, If True, an exception is raised if an inconsistency is detected in the number of columns. If False, a warning is emitted and the offending lines are skipped. + nrows : int, optional + The number of rows to read. Must not be used with skip_footer at the + same time. + + .. versionadded:: 1.10.0 Returns ------- @@ -1353,6 +1359,12 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None, dtype=[('intvar', '<i8'), ('fltvar', '<f8'), ('strvar', '|S5')]) """ + # Check keywords conflict + if skip_footer and (nrows is not None): + raise ValueError( + "keywords 'skip_footer' and 'nrows' can not be specified " + "at the same time") + # Py3 data conversions to bytes, for convenience if comments is not None: comments = asbytes(comments) @@ -1642,6 +1654,8 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None, # Parse each line for (i, line) in enumerate(itertools.chain([first_line, ], fhd)): + if (nrows is not None) and (len(rows) >= nrows): + break values = split_line(line) nbvalues = len(values) # Skip an empty line @@ -1666,6 +1680,11 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None, if own_fhd: fhd.close() + if (nrows is not None) and (len(rows) != nrows): + raise AssertionError( + "%d rows required but got %d valid rows instead" + %(nrows, len(rows))) + # Upgrade the converters (if needed) if dtype is None: for (i, converter) in enumerate(converters): |