NumPy

Previous topic

numpy.copy

Next topic

numpy.fromfile

This is documentation for an old release of NumPy (version 1.18). Read this page in the documentation of the latest stable release (version 2.2).

numpy.frombuffer

numpy.frombuffer(buffer, dtype=float, count=-1, offset=0)

Interpret a buffer as a 1-dimensional array.

Parameters
bufferbuffer_like

An object that exposes the buffer interface.

dtypedata-type, optional

Data-type of the returned array; default: float.

countint, optional

Number of items to read. -1 means all data in the buffer.

offsetint, optional

Start reading the buffer from this offset (in bytes); default: 0.

Notes

If the buffer has data that is not in machine byte-order, this should be specified as part of the data-type, e.g.:

>>>
>>> dt = np.dtype(int)
>>> dt = dt.newbyteorder('>')
>>> np.frombuffer(buf, dtype=dt) 

The data of the resulting array will not be byteswapped, but will be interpreted correctly.

Examples

>>>
>>> s = b'hello world'
>>> np.frombuffer(s, dtype='S1', count=5, offset=6)
array([b'w', b'o', b'r', b'l', b'd'], dtype='|S1')
>>>
>>> np.frombuffer(b'\x01\x02', dtype=np.uint8)
array([1, 2], dtype=uint8)
>>> np.frombuffer(b'\x01\x02\x03\x04\x05', dtype=np.uint8, count=3)
array([1, 2, 3], dtype=uint8)