diff options
Diffstat (limited to 'numpy/core/records.py')
| -rw-r--r-- | numpy/core/records.py | 41 |
1 files changed, 19 insertions, 22 deletions
diff --git a/numpy/core/records.py b/numpy/core/records.py index 86a43306a..ff2a3ef9f 100644 --- a/numpy/core/records.py +++ b/numpy/core/records.py @@ -7,10 +7,9 @@ Most commonly, ndarrays contain elements of a single type, e.g. floats, integers, bools etc. However, it is possible for elements to be combinations of these using structured types, such as:: - >>> a = np.array([(1, 2.0), (1, 2.0)], dtype=[('x', int), ('y', float)]) + >>> a = np.array([(1, 2.0), (1, 2.0)], dtype=[('x', np.int64), ('y', np.float64)]) >>> a - array([(1, 2.0), (1, 2.0)], - dtype=[('x', '<i4'), ('y', '<f8')]) + array([(1, 2.), (1, 2.)], dtype=[('x', '<i8'), ('y', '<f8')]) Here, each element consists of two fields: x (and int), and y (a float). This is known as a structured array. The different fields are analogous @@ -21,7 +20,7 @@ one would a dictionary:: array([1, 1]) >>> a['y'] - array([ 2., 2.]) + array([2., 2.]) Record arrays allow us to access fields as properties:: @@ -31,7 +30,7 @@ Record arrays allow us to access fields as properties:: array([1, 1]) >>> ar.y - array([ 2., 2.]) + array([2., 2.]) """ from __future__ import division, absolute_import, print_function @@ -128,10 +127,9 @@ class format_parser(object): Examples -------- - >>> np.format_parser(['f8', 'i4', 'a5'], ['col1', 'col2', 'col3'], + >>> np.format_parser(['<f8', '<i4', '<a5'], ['col1', 'col2', 'col3'], ... ['T1', 'T2', 'T3']).dtype - dtype([(('T1', 'col1'), '<f8'), (('T2', 'col2'), '<i4'), - (('T3', 'col3'), '|S5')]) + dtype([(('T1', 'col1'), '<f8'), (('T2', 'col2'), '<i4'), (('T3', 'col3'), 'S5')]) `names` and/or `titles` can be empty lists. If `titles` is an empty list, titles will simply not appear. If `names` is empty, default field names @@ -139,9 +137,9 @@ class format_parser(object): >>> np.format_parser(['f8', 'i4', 'a5'], ['col1', 'col2', 'col3'], ... []).dtype - dtype([('col1', '<f8'), ('col2', '<i4'), ('col3', '|S5')]) - >>> np.format_parser(['f8', 'i4', 'a5'], [], []).dtype - dtype([('f0', '<f8'), ('f1', '<i4'), ('f2', '|S5')]) + dtype([('col1', '<f8'), ('col2', '<i4'), ('col3', '<S5')]) + >>> np.format_parser(['<f8', '<i4', '<a5'], [], []).dtype + dtype([('f0', '<f8'), ('f1', '<i4'), ('f2', 'S5')]) """ @@ -380,20 +378,19 @@ class recarray(ndarray): -------- Create an array with two fields, ``x`` and ``y``: - >>> x = np.array([(1.0, 2), (3.0, 4)], dtype=[('x', float), ('y', int)]) + >>> x = np.array([(1.0, 2), (3.0, 4)], dtype=[('x', '<f8'), ('y', '<i8')]) >>> x - array([(1.0, 2), (3.0, 4)], - dtype=[('x', '<f8'), ('y', '<i4')]) + array([(1., 2), (3., 4)], dtype=[('x', '<f8'), ('y', '<i8')]) >>> x['x'] - array([ 1., 3.]) + array([1., 3.]) View the array as a record array: >>> x = x.view(np.recarray) >>> x.x - array([ 1., 3.]) + array([1., 3.]) >>> x.y array([2, 4]) @@ -580,7 +577,7 @@ def fromarrays(arrayList, dtype=None, shape=None, formats=None, >>> x3=np.array([1.1,2,3,4]) >>> r = np.core.records.fromarrays([x1,x2,x3],names='a,b,c') >>> print(r[1]) - (2, 'dd', 2.0) + (2, 'dd', 2.0) # may vary >>> x1[1]=34 >>> r.a array([1, 2, 3, 4]) @@ -659,11 +656,11 @@ def fromrecords(recList, dtype=None, shape=None, formats=None, names=None, >>> r.col1 array([456, 2]) >>> r.col2 - array(['dbe', 'de'], - dtype='|S3') + array(['dbe', 'de'], dtype='<U3') >>> import pickle - >>> print(pickle.loads(pickle.dumps(r))) - [(456, 'dbe', 1.2) (2, 'de', 1.3)] + >>> pickle.loads(pickle.dumps(r)) + rec.array([(456, 'dbe', 1.2), ( 2, 'de', 1.3)], + dtype=[('col1', '<i8'), ('col2', '<U3'), ('col3', '<f8')]) """ if formats is None and dtype is None: # slower @@ -750,7 +747,7 @@ def fromfile(fd, dtype=None, shape=None, offset=0, formats=None, >>> a = a.newbyteorder('<') >>> a.tofile(fd) >>> - >>> fd.seek(0) + >>> _ = fd.seek(0) >>> r=np.core.records.fromfile(fd, formats='f8,i4,a5', shape=10, ... byteorder='<') >>> print(r[5]) |