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[python #GPD-109280]: MetPy Monday #89 Code Question

Greetings!

The approach taken in that video is handling the fact that the points that were 
given in the shapefile were coordinates in a Lambert Conformal Conic (LCC) 
projection. My best guess is SPC previously generated the points directly in an 
LCC projection and shipped those raw points in the shapefile; then, recently, 
they started sending out those points converted to lat/lon coordinates instead.

Regardless, I was able to make things work by changing the offending line to 
`data_crs = ccrs.PlateCarree()`

So the complete set of functional code is:

    import matplotlib.pyplot as plt
    import geopandas
    from cartopy import crs as ccrs
    import cartopy.feature as cfeature
    %matplotlib inline
    
    cat_gdf = geopandas.read_file('./day1otlk-shp/day1otlk_cat.shp')
    cat_gdf.plot()
    
    map_crs = ccrs.LambertConformal(central_latitude = 35, central_longitude = 
-100, standard_parallels = (30, 60))
    data_crs = ccrs.PlateCarree()
    
    cat_plot_colors = {2: 'palegreen', 3: 'green', 4: 'yellow', 5: 'brown', 6: 
'red', 7: 'magenta'}
    
    fig = plt.figure(1, figsize = (14, 12))
    ax = plt.subplot(1, 1, 1, projection = map_crs)
    ax.set_extent([-130, -72, 20, 55], ccrs.PlateCarree())
    
    ax.add_feature(cfeature.COASTLINE.with_scale('50m'))
    ax.add_feature(cfeature.STATES.with_scale('50m'))
    
    for key in cat_plot_colors.keys():
        geometries = cat_gdf[cat_gdf['DN'] == key]
        if len(geometries) > 0:
                ax.add_geometries(geometries['geometry'], crs = data_crs, 
facecolor = cat_plot_colors[key], edgecolor = 'black', alpha = 0.5)

Cheers!

Ryan

> I’m having trouble with the code outlined in one of the MetPy Monday video 
> tutorials for the SPC convective outlook maps.
> 
> Line 8 of the code in the video is ---
> data_crs = ccrs.LambertConformal(central_latitude=cat_gdf.crs['lat_0'], 
> central_longitude=cat_gdf.crs['lon_0'],
> standard_parallels=(cat_gdf.crs['lat_1'], cat_gdf.crs['lat_2']))
> 
> This works fine, obviously, in the video.  However, when I go to put this 
> into my system, I get a “TypeError: ‘CRS’ object is not subscriptable” 
> message.  Is there a fix or a workaround for this line of code to work so 
> that the rest of the code works and the map can be plotted?
> 
> Thanks for any input and help!


Ticket Details
===================
Ticket ID: GPD-109280
Department: Support Python
Priority: Low
Status: Closed
===================
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