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numpy.core.records.fromrecords

This is documentation for an old release of NumPy (version 1.19). Read this page in the documentation of the latest stable release (version 2.2).

numpy.core.records.fromarrays

numpy.core.records.fromarrays(arrayList, dtype=None, shape=None, formats=None, names=None, titles=None, aligned=False, byteorder=None)[source]

Create a record array from a (flat) list of arrays

Parameters
arrayListlist or tuple

List of array-like objects (such as lists, tuples, and ndarrays).

dtypedata-type, optional

valid dtype for all arrays

shapeint or tuple of ints, optional

Shape of the resulting array. If not provided, inferred from arrayList[0].

formats, names, titles, aligned, byteorder :

If dtype is None, these arguments are passed to numpy.format_parser to construct a dtype. See that function for detailed documentation.

Returns
np.recarray

Record array consisting of given arrayList columns.

Examples

>>>
>>> x1=np.array([1,2,3,4])
>>> x2=np.array(['a','dd','xyz','12'])
>>> 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) # may vary
>>> x1[1]=34
>>> r.a
array([1, 2, 3, 4])
>>>
>>> x1 = np.array([1, 2, 3, 4])
>>> x2 = np.array(['a', 'dd', 'xyz', '12'])
>>> x3 = np.array([1.1, 2, 3,4])
>>> r = np.core.records.fromarrays(
...     [x1, x2, x3],
...     dtype=np.dtype([('a', np.int32), ('b', 'S3'), ('c', np.float32)]))
>>> r
rec.array([(1, b'a', 1.1), (2, b'dd', 2. ), (3, b'xyz', 3. ),
           (4, b'12', 4. )],
          dtype=[('a', '<i4'), ('b', 'S3'), ('c', '<f4')])