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[python #PHR-160601]: MetPy Help

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  • Subject: [python #PHR-160601]: MetPy Help
  • Date: Wed, 03 Mar 2021 11:37:16 -0700
Greetings!

Getting my hands on the data made this much easier to track down. The problem 
is an issue with numpy broadcasting--how it matches up arrays of different 
dimensions to do calculations. The solution, in addition to making sure you've 
included np.array() when creating levs, u, v, is to change the call to 
`mc.potential_vorticity_baroclinic` to:

    pv = mc.potential_vorticity_baroclinic(pot_temp, levs[:, None, None], u, v, 
dx=dx[None], dy=dy[None], latitude=lats)

What the additional indexing in that line does is add dummy dimensions in the 
correct spot to make all of the arrays 3-dimensional, so that everything lines 
up properly. For more information on broadcasting in NumPy, checkout these 
pages:

  https://numpy.org/doc/stable/user/basics.broadcasting.html
  
https://numpy.org/doc/stable/user/theory.broadcasting.html#array-broadcasting-in-numpy

Cheers!

Ryan

> Hi Ryan,
> 
> Great! Here is the location of the file on
> cheyenne: . Please let me know if you
> run into any issues.


Ticket Details
===================
Ticket ID: PHR-160601
Department: Support Python
Priority: Low
Status: Closed
===================
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