[python-control-discuss] __repr__

[Ryan K. <rk...@si...>]

I probably won't get to this one for a few weeks (I have a conference and
another paper coming up), but I would like to contribute a __repr__ method
for TransferFunctions if it would be welcome.  I personally would prefer
that when I type the name of a TransferFunction instance and hit enter that
it pretty print an ascii numerator and denominator and a horizontal line.
 It might be tricky to do it really nicely with exponents, but this is what
happend now:

In [2]: G = control.TransferFunction(1,[1,2])

In [3]: G
Out[3]: <control.xferfcn.TransferFunction instance at 0x10e94cf80>

I then have to ask ro G.num and G.den separately, which I personally don't
like.

I see that there is a __str__ method which pretty much does what I would
want, so that "print G" gives me an ascii representation.

Is there any reason not to have __repr__ simply call __str__?  Is there
some historical reason to have one and not the other?

--
Ryan Krauss, Ph.D.
Associate Professor
Mechanical Engineering
Southern Illinois University Edwardsville