cuda.py 文件源码

def __getitem__(self, slc):
            if isinstance(slc, slice):
                slc = [slc]
            start, shape = [], []
            for s, n in zip(slc, self.shape):
                if isinstance(s, int):
                    s = slice(s, s+1)
                b, e = s.start or 0, s.stop or n
                if b < 0: b = n+b # remove neg begining indices
                if e < 0: e = n+e # remove neg ending indices
                if e < b: e = b   # disallow negative sizes
                if e > n: e = n   # fix over-slices
                start.append(b)
                shape.append(e-b)
            idx = np.ravel_multi_index(start, self.shape, order='F')
            ptr = self._arr.value + idx * np.dtype(self.dtype).itemsize
            ptr = c_ulong(ptr)
            ld = self._leading_dim
            return self._backend.dndarray(self._backend, tuple(shape),
                self.dtype, ld=ld, own=False, data=ptr)