test_multiarray.py 文件源码

def test_big_binary(self):
        """Test workarounds for 32-bit limited fwrite, fseek, and ftell
        calls in windows. These normally would hang doing something like this.
        See http://projects.scipy.org/numpy/ticket/1660"""
        if sys.platform != 'win32':
            return
        try:
            # before workarounds, only up to 2**32-1 worked
            fourgbplus = 2**32 + 2**16
            testbytes = np.arange(8, dtype=np.int8)
            n = len(testbytes)
            flike = tempfile.NamedTemporaryFile()
            f = flike.file
            np.tile(testbytes, fourgbplus // testbytes.nbytes).tofile(f)
            flike.seek(0)
            a = np.fromfile(f, dtype=np.int8)
            flike.close()
            assert_(len(a) == fourgbplus)
            # check only start and end for speed:
            assert_((a[:n] == testbytes).all())
            assert_((a[-n:] == testbytes).all())
        except (MemoryError, ValueError):
            pass