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[python #KDL-157609]: Intern for Nick Lilja

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  • Subject: [python #KDL-157609]: Intern for Nick Lilja
  • Date: Fri, 26 Jun 2020 15:44:57 -0600
Hello! Thanks for reaching out.

Apologies for the delay in responding. I've put together for you a short 
Jupyter notebook demonstration available on GitHub

  https://gist.github.com/dcamron/f55df1d59a8972c320ea1773416ce029

to highlight what interacting with GRIB files with pygrib can look like. Pygrib 
will return your output from `gribmessage.values` as a NumPy array or 
maskedarray. The corresponding latitudes and longitudes that come out of 
`gribmessage.latlons()` should mirror the shape of your data values and allow 
you to dig into plotting. Our python-training website 
https://unidata.github.io/python-training/) has various examples for using 
cartopy for map-style plots and displays!

I hope this helps. If I didn't quite help with where you're at, don't hesitate 
to follow up and let me know and I should be able to respond to you much 
quicker this time! I may also take some time to update that notebook with a 
plotting example if it would help. Thanks again for reaching out.


All the best,

Drew


> To whom this concerns,
> 
> I have a few questions about using Python and the 'pygrib' library for 
> interacting with '.grib2' files.
> 
> I'm trying to grab the hour, temperature, lat, lon, and precipitation values 
> from a .grib2 dataset.
> 
> When printing a line in the dataset, output looks like this:
> 38:Temperature:K (instant):lambert:isobaricInhPa:level 100000 Pa:fcst time 1 
> hrs:from 20131206050
> 
> According to 
> http://www.himpactwxlab.com/home/how-to-wiki/write-grib2-data-with-pygrib#TOC-Get-values-associated-with-the-grib-message,
>  I can use '.select()' to grab keys then use '.values' to extract the values 
> from the respective keys.
> 
> The problem is, I'm having trouble correctly hitting the right keys, and 
> pulling the correct values. For example, after selecting the 'Temperature' 
> key and printing out the values, the output is lists of lists of 
> temperatures. The output doesn't makes sense to me to graph it.
> 
> How do I grab the right keys, and get the right values?
> 
> 

Ticket Details
===================
Ticket ID: KDL-157609
Department: Support Python
Priority: Low
Status: Closed
===================
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