US Census

import pandas as pd
import geopandas as gpd

# path where 2020_PLSummaryFile_FieldNames.xlsx XX=State Code
# and XXgeo2020.pl, xx000012020.pl through XX000032020.pl
# reside on your hard drive
path='/home/andy/Desktop/2020pl-94-171/'

# state code
state='ny'

# header file, open with all tabs as an dictionary of dataframes
field_names=pd.read_excel(path+'2020_PLSummaryFile_FieldNames.xlsx', sheet_name=None)

# load the geoheader, force as str type to mixed types on certain fields
# ensure GEOIDs are properly processed avoids issues with paging
gh=pd.read_csv( path+state+'geo2020.pl',delimiter='|',
               header=None, 
               names=field_names['2020 P.L. Geoheader Fields'].columns,
               index_col='LOGRECNO',
               dtype=str )
               
 # load segment 1 of 2020 PL 94-171 which is racial data 
segNum=1
seg=pd.read_csv( path+state+'0000'+str(segNum)+'2020.pl',delimiter='|',
               header=None, 
               names=field_names['2020 P.L. Segment '+str(segNum)+' Fields'].columns,
               index_col='LOGRECNO',
              )
# discard FILEID, STUSAB, CHARITER, CIFSN as duplicative after join
seg=seg.iloc[:,4:]

# join seg to geoheader
seg=gh.join(seg)

# Calculate the population of New York Counties that is African American 
# using County SUMLEVEL == 50 (see Census Docts)
ql="SUMLEV=='050'"

# Create a DataFrame with the County and Percent Hispani
# You can get the fields list from 2020 PL Summary FieldNames.xlsx
# under the 2020 P.L. Segment 1 Definitions tab
his=pd.DataFrame({ 'County': seg.query(ql)['BASENAME'], 
              'Percent Hispanic': seg.query(ql)['P0020002'] / seg.query(ql)['P0020001'] *100})

# Sort and print most Hispanic Counties
his.sort_values(by="Percent Hispanic", ascending=False).head(10).to_csv('/tmp/hispanics.csv')