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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)