Indexer doesn't return matrix

[henon]

The code only return a single value, b = {0}, not a matrix.

Originally posted by @JimXu1989 in #89 (comment)

[henon]

@JimXu1989 that is far too few information. You need to give me a simple snippet that I can use to reproduce your problem. If possible give me also the according python output so I see what would be the correct return value.