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[python #COB-992724]: CAPE/LFC Calculations Questions/Bug?

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  • Subject: [python #COB-992724]: CAPE/LFC Calculations Questions/Bug?
  • Date: Tue, 19 Sep 2017 13:51:45 -0600
Brad,

Sadly, yes you'll need to manually affix units to the columns. The data frame 
returned from `request_data` will have an attribute `units` that is a 
dictionary mapping each of the column names to the units as a string.

For now what you'll need to do is something like:

press = dataset2['pressure'].values * units(dataset2.units['pressure'])

Note the use of `values` to get the pandas column as a numpy array (it doesn't 
work otherwise). You can also hard-code the units instead of using the 
`units['pressure']` type of construct.

I would very much like to clean this up and make it simpler, but for now that's 
where things stand.

Ryan

> Ryan,
> 
> Thanks for the response. Regarding the siphon data and its panda format, I 
> modified my script to just start testing things out. I had a question 
> regarding units of the data.
> 
> dataset2 = WyomingUpperAir.request_data(datetime(1999, 5, 4, 0), 'OUN')
> prof_m21 = mpcalc.parcel_profile(dataset2['pressure'], T[0], 
> Td_m20[0]).to('degC')
> 
> But I get the following error:
> 
> ValueError: `parcel_profile` given arguments with incorrect units: `pressure` 
> requires "[pressure]" but given "none".
> Any variable `x` can be assigned a unit as follows:
> from metpy.units import units
> x = x * units.meter / units.second
> 
> Do I need to set the units for each panda column? Is this something siphon 
> should/can/does return?

Ticket Details
===================
Ticket ID: COB-992724
Department: Support Python
Priority: Low
Status: Closed
===================
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