It's not described in the standard. I prefer no shape N or (N, M) at all unless N, M are used later in the description. Otherwise I think it's better to just say 1-D or 2-D. But there were so many changes like this that I left them where they were consistently done at some point (I reverted lots of them too).

To be honest, it was a little frustrating to have to put in so much effort for this kind of thing in the doc wiki . I already spent a full day reviewing changes to ~400 docstrings. That's why I left this as is.