使用numpy.load从文件中加载压缩数据(.npz)
问题内容:
我有一个数组:
>>> data = np.ones((1,3,128))
我将其保存到文件中savez_compressed
:
>>> with open('afile','w') as f:
np.savez_compressed(f,data=data)
当我尝试加载它时,我似乎无法访问数据:
>>> with open('afile','r') as f:
b=np.load(f)
>>> b.files
['data']
>>> b['data']
Traceback (most recent call last):
File "<pyshell#196>", line 1, in <module>
b['data']
File "C:\Python27\lib\site-packages\numpy\lib\npyio.py", line 238, in __getitem__
bytes = self.zip.read(key)
File "C:\Python27\lib\zipfile.py", line 828, in read
return self.open(name, "r", pwd).read()
File "C:\Python27\lib\zipfile.py", line 853, in open
zef_file.seek(zinfo.header_offset, 0)
ValueError: I/O operation on closed file
我做错了什么吗?
编辑
按照@Saullo Castro的回答,我尝试了以下操作:
>>> np.savez_compressed('afile.npz',data=data)
>>> b=np.load('afile.npz')
>>> b.files
['data']
>>> b['data']
并得到以下错误:
Traceback (most recent call last):
File "<pyshell#253>", line 1, in <module>
b['data']
File "C:\Python27\lib\site-packages\numpy\lib\npyio.py", line 241, in __getitem__
return format.read_array(value)
File "C:\Python27\lib\site-packages\numpy\lib\format.py", line 440, in read_array
shape, fortran_order, dtype = read_array_header_1_0(fp)
File "C:\Python27\lib\site-packages\numpy\lib\format.py", line 336, in read_array_header_1_0
d = safe_eval(header)
File "C:\Python27\lib\site-packages\numpy\lib\utils.py", line 1156, in safe_eval
ast = compiler.parse(source, mode="eval")
File "C:\Python27\lib\compiler\transformer.py", line 53, in parse
return Transformer().parseexpr(buf)
File "C:\Python27\lib\compiler\transformer.py", line 132, in parseexpr
return self.transform(parser.expr(text))
File "C:\Python27\lib\compiler\transformer.py", line 124, in transform
return self.compile_node(tree)
File "C:\Python27\lib\compiler\transformer.py", line 159, in compile_node
return self.eval_input(node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 194, in eval_input
return Expression(self.com_node(nodelist[0]))
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 578, in testlist
return self.com_binary(Tuple, nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 1082, in com_binary
return self.lookup_node(n)(n[1:])
File "C:\Python27\lib\compiler\transformer.py", line 596, in test
then = self.com_node(nodelist[0])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 610, in or_test
return self.com_binary(Or, nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 1082, in com_binary
return self.lookup_node(n)(n[1:])
File "C:\Python27\lib\compiler\transformer.py", line 615, in and_test
return self.com_binary(And, nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 1082, in com_binary
return self.lookup_node(n)(n[1:])
File "C:\Python27\lib\compiler\transformer.py", line 619, in not_test
result = self.com_node(nodelist[-1])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 626, in comparison
node = self.com_node(nodelist[0])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 659, in expr
return self.com_binary(Bitor, nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 1082, in com_binary
return self.lookup_node(n)(n[1:])
File "C:\Python27\lib\compiler\transformer.py", line 663, in xor_expr
return self.com_binary(Bitxor, nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 1082, in com_binary
return self.lookup_node(n)(n[1:])
File "C:\Python27\lib\compiler\transformer.py", line 667, in and_expr
return self.com_binary(Bitand, nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 1082, in com_binary
return self.lookup_node(n)(n[1:])
File "C:\Python27\lib\compiler\transformer.py", line 671, in shift_expr
node = self.com_node(nodelist[0])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 683, in arith_expr
node = self.com_node(nodelist[0])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 695, in term
node = self.com_node(nodelist[0])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 715, in factor
node = self.lookup_node(nodelist[-1])(nodelist[-1][1:])
File "C:\Python27\lib\compiler\transformer.py", line 727, in power
node = self.com_node(nodelist[0])
File "C:\Python27\lib\compiler\transformer.py", line 805, in com_node
return self._dispatch[node[0]](node[1:])
File "C:\Python27\lib\compiler\transformer.py", line 739, in atom
return self._atom_dispatch[nodelist[0][0]](nodelist)
File "C:\Python27\lib\compiler\transformer.py", line 754, in atom_lbrace
return self.com_dictorsetmaker(nodelist[1])
File "C:\Python27\lib\compiler\transformer.py", line 1214, in com_dictorsetmaker
assert nodelist[0] == symbol.dictorsetmaker
AssertionError
编辑2
上面的错误是在IDLE中。它使用Ipython工作。
问题答案:
使用时,numpy.load
您可以传递文件名,如果扩展名为.npz
,它将首先解压缩该文件:
np.savez_compressed('filename.npz', array1=array1, array2=array2)
b = np.load('filename.npz')
然后执行b['array1']
以此类推以从每个数组中检索数据…