Use of Parallel Screens

[smngr]

I've noticed that the Parallel Screens class doesn't check the size of the input array, so if you give it (t, x1, y1, z1, x2, y2, z2) then it inserts more separation columns. This leads to confusion for some users who now have a 9-column LOR array. Perhaps catching this and warning the user would be useful.

[anicusan]

We have relaxed the requirement for LineData to have exactly 7 columns to allow users to have any other attributes as extra columns, same as with PointData. But I see your point on how people might use ParallelScreens with lines that already have 7 columns formatted as [time, x1, y1, z1, x2, y2, z2] (which should go into the standard LineData directly).

I will add a warning when ParallelScreens is instantiated with data that has exactly 7 columns.