NumPy Data type: dtype() function

Last update on August 19 2022 21:50:38 (UTC/GMT +8 hours)

numpy.dtype() function

The dtype() function is used to create a data type object.

A numpy array is homogeneous, and contains elements described by a dtype object. A dtype object can be constructed from different combinations of fundamental numeric types.

Version: 1.15.0

Syntax:

class numpy.dtype(obj, align=False, copy=False)

Parameter:

Name	Description	Required / Optional
obj	Object to be converted to a data type object.	Required
align	Add padding to the fields to match what a C compiler would output for a similar C-struct. Can be True only if obj is a dictionary or a comma-separated string. If a struct dtype is being created, this also sets a sticky alignment flag isalignedstruct.	Optional
copy : bool,	Make a new copy of the data-type object. If False, the result may just be a reference to a built-in data-type object.	optional

Return value:

dtype : dtype or Python type - The data type of rep.

Example: numpy.dtype() function

>>> import numpy as np
>>> np.dtype(np.int16)
dtype('int16')
>>> np.dtype([('f1', np.int16)])
dtype([('f1', '<i2')])
>>> np.dtype([('f1', [('f1', np.int16)])])
dtype([('f1', [('f1', '<i2')])])
>>> np.dtype([('f1', np.uint), ('f2', np.int32)])
dtype([('f1', '<u8'), ('f2', '<i4')])
>>> np.dtype([('a','f8'),('b','S10')])
dtype([('a', '<f8'), ('b', 'S10')])
>>> np.dtype("i4, (2,3)f8")
dtype([('f0', '<i4'), ('f1', '<f8', (2, 3))])
>>> np.dtype([('hello',(int,3)),('world',np.void,10)])
dtype([('hello', '<i8', (3,)), ('world', 'V10')])
>>> np.dtype((np.int16, {'x':(np.int8,0), 'y':(np.int8,1)}))
dtype([('x', 'i1'), ('y', 'i1')])
>>> np.dtype({'names':['gender','age'], 'formats':['S1',np.uint8]})
dtype([('gender', 'S1'), ('age', 'u1')])
>>> np.dtype({'surname':('S25',0),'age':(np.uint8,25)})
dtype([('surname', 'S25'), ('age', 'u1')])

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