Sw find layer depths
New utility function to return time series of depths of the middle of each vertical layer for one or more elements. This is useful when producing outputs, e.g. comparisons with ADCPs, where tidal range is large and one needs to take account of zeta as well as h when computing the vertical positions of layers.
I don't think there's already something that does this in the toolbox... but I don't claim to be familiar with every thing that's there!