> My only caveat is that I don’t think tracking physical units should be a 
> primary use case. Units are fundamentally different than data types, even 
> though there are libraries out there that treat them more like data types.
> 
> I strongly disagree. Right now, you need to implement a custom container to 
> handle units, which makes it exceedingly difficult to then properly interact 
> with other array_like objects, like dask, pandas, and xarray; handling units 
> is completely orthogonal to handling slicing operations, data access, etc. so 
> having to implement a container is overkill. Unit information describes 
> information about the type of each of the elements within an array, including 
> describing how operations between individual elements work. This sounds 
> exactly like a dtype to me.

Yes I see your point.

> Finally, units may be different for each axis in multidimensional data. For 
> instance, we want a float32 array with two dimensions with the units on one 
> dimension being time and the other dimension being spatial. (3 seconds x 50 
> nm).
> 
> The units for an array describe the elements *within* the array, they would 
> have nothing to do with the dimensions. So for an array of image data, e.g. 
> brightness temperatures, you would have physical units (e.g. Kelvin). You 
> would have separate arrays of coordinates describing the spatial extent of 
> the data along the relevant dimensions--each of these arrays of coordinates 
> would have their own physical quantity information.

Again, you are correct. I’m asking for similar metadata attached to the data 
shape rather than the data type.

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