【python】numpy数据load报错

使用numpy.load(‘xxx.npy’)数据时，报错UnicodeError: Unpickling a python object failed: UnicodeDecodeError

解决办法

由于默认编码问题，造成无法对数据解包：
encoding must be 'ASCII', 'latin1', or 'bytes'
所以在使用np.load()时需要加入编码选项：
data = np.load('mynpy.npy',encoding='latin1')
即可顺利载入。

原因

如果使用python3读取python2生成的npy就有可能产生编码错误，在numpy的源码里有说明：

# https://github.com/numpy/numpy/blob/v1.16.1/numpy/lib/npyio.py#L287-L453
# line 317
encoding : str, optional
        What encoding to use when reading Python 2 strings. Only useful when
        loading Python 2 generated pickled files in Python 3, which includes
        npy/npz files containing object arrays. Values other than 'latin1',
        'ASCII', and 'bytes' are not allowed, as they can corrupt numerical
        data. Default: 'ASCII'


# 编码方式只允许选择下面三个中的一个
# line 390
if encoding not in ('ASCII', 'latin1', 'bytes'):
        # The 'encoding' value for pickle also affects what encoding
        # the serialized binary data of NumPy arrays is loaded
        # in. Pickle does not pass on the encoding information to
        # NumPy. The unpickling code in numpy.core.multiarray is
        # written to assume that unicode data appearing where binary
        # should be is in 'latin1'. 'bytes' is also safe, as is 'ASCII'.
        #
        # Other encoding values can corrupt binary data, and we
        # purposefully disallow them. For the same reason, the errors=
        # argument is not exposed, as values other than 'strict'
        # result can similarly silently corrupt numerical data.
        raise ValueError("encoding must be 'ASCII', 'latin1', or 'bytes'")

ref:
numpy:https://docs.scipy.org/doc/numpy/reference/generated/numpy.load.html
https://blog.csdn.net/qq_36718092/article/details/87983922