Question

I have a class, Matrix, i would like when print is called on this class, instead of printing

<main.Matrix instance at 0x7f41fb17de18>

I would like to be able to control the output something like

0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 0

In C++ i would just overload the << operator. How can i do this in python 3?

Answer 1

If you want to produce a printable output, implement __str__. You can also implement __repr__ but is usually used to create a more technical representation instead of just a human-readable output.

>>> class MyType:
        def __str__ (self):
            return 'foo'
>>> print(MyType())
foo