I'm a beginner in Python.
Now I have 2 columns on my Excel file. One is country column and the other one is city column.
For the country column, most of the values are shown in country code and some of them are shown in country full name, while some values are U.S.A states code and less than 1% of them are blank.
For the city column, it clearly shows the full city name (not city code), while nearly 20% of them are blank.
How can I use Python to create a new column to show the full country name based on the country code and remain the same name if it shows the full country name in the country column, and show the U.S.A states code as the United States in the new column?
The tricky part is, in the country column, take CO as the example, Co can stand for Columbia and Colorado, I cannot be sure whether it's a country or a state at the beginning, but when I check the corresponding city name I can know it's a country or a state (ex: Longmont for Colorado, Bogota for Columbia). How can I avoid this issue in the new column and infer the full country name in the new column based on the corresponding city name?
I appreciate your help!
Explanation
Coded the task using following logic.
Note: String matching uses fuzzy matching to allow for flexibility in spelling of names rapidfuzz library was used over fuzzywuzzy since its an order of magnitude faster
Code
import pandas as pd
from rapidfuzz import fuzz
def find_closest_country(country):
' Country with the closest name in list of countries in country code '
ratios = [fuzz.partial_ratio(country, x) for x in alpha2.values()]
rated_countries = [(info, r) for info, r in zip(alpha2.values(), ratios)]
# Best match with shortest name
return sorted(rated_countries, key = lambda x: (x[1], -len(x[0])), reverse = True)[0]
def check_city_country(city, country):
' City, Country pair closest in list of cities '
ratios = [fuzz.partial_ratio(city, x['name']) * fuzz.partial_ratio(country, x['country']) for x in cities]
rated_cities = [(info, r) for info, r in zip(cities, ratios)]
# Best match with shortest name
return sorted(rated_cities, key = lambda x: (x[1], -len(x[0])), reverse = True)[0]
def check_city_subregion(city, subregion):
' City, subresion pair closest in list of cities '
ratios = [fuzz.partial_ratio(city, x['name']) * fuzz.partial_ratio(subregion, x['subcountry']) for x in cities]
rated_cities = [(info, r) for info, r in zip(cities, ratios)]
# Best match with shortest name
return sorted(rated_cities, key = lambda x: (x[1], -len(x[0])), reverse = True)[0]
def lookup(country, city):
'''
Finds country based upon country and city
country - country name or country code
city - name of city
'''
if country.lower() == 'u.s.':
# Picks up common US acronym
country = "US"
if len(country) > 3:
# Must be country since too long for abbreviation
if city:
# Find closest city country pair in list of cities
city_info = check_city_country(city, country)
if city_info:
return city_info[0]['country']
# No city, so find closest country in list of countries (2 code abbreviations reverse lookup)
countries = find_closest_country(country)
if countries:
return countries[0]
return None
elif len(country) == 3:
# 3 letter abbreviation
country = country.upper()
return alpha3.get(country, None)
elif len(country) == 2:
# Two letter country abbreviation
country = country.upper()
if not country in states:
# Not a state code, so lookup contry from code
return alpha2.get(country, None)
if not country in alpha2:
# Not a country code, so must be state code for US
return "United States of America"
# Could be country of state code
if city:
# Have 2 digit code (could be country or state)
pos_country = alpha2[country] # possible country
pos_state = states[country] # possible state
# check closest country with this city
pos_countries = check_city_country(city, pos_country)
# If state code, country would be United States
pos_us = check_city_country(city, "United States")
if pos_countries[1] > pos_us[1]:
# Provided better match as country code
return pos_countries[0]['country']
else:
# Provided better match as state code (i.e. "United States")
return pos_us[0]['country']
else:
return alpha2[country]
else:
return None
Data
# State Codes
# https://gist.github.com/rugbyprof/76575b470b6772ce8fa0c49e23931d97
states = {"AL":"Alabama","AK":"Alaska","AZ":"Arizona","AR":"Arkansas","CA":"California","CO":"Colorado","CT":"Connecticut","DE":"Delaware","FL":"Florida","GA":"Georgia","HI":"Hawaii","ID":"Idaho","IL":"Illinois","IN":"Indiana","IA":"Iowa","KS":"Kansas","KY":"Kentucky","LA":"Louisiana","ME":"Maine","MD":"Maryland","MA":"Massachusetts","MI":"Michigan","MN":"Minnesota","MS":"Mississippi","MO":"Missouri","MT":"Montana","NE":"Nebraska","NV":"Nevada","NH":"New Hampshire","NJ":"New Jersey","NM":"New Mexico","NY":"New York","NC":"North Carolina","ND":"North Dakota","OH":"Ohio","OK":"Oklahoma","OR":"Oregon","PA":"Pennsylvania","RI":"Rhode Island","SC":"South Carolina","SD":"South Dakota","TN":"Tennessee","TX":"Texas","UT":"Utah","VT":"Vermont","VA":"Virginia","WA":"Washington","WV":"West Virginia","WI":"Wisconsin","WY":"Wyoming"}
# two letter country codes
# https://gist.github.com/carlopires/1261951/d13ca7320a6abcd4b0aa800d351a31b54cefdff4
alpha2 = {
'AD': 'Andorra',
'AE': 'United Arab Emirates',
'AF': 'Afghanistan',
'AG': 'Antigua & Barbuda',
'AI': 'Anguilla',
'AL': 'Albania',
'AM': 'Armenia',
'AN': 'Netherlands Antilles',
'AO': 'Angola',
'AQ': 'Antarctica',
'AR': 'Argentina',
'AS': 'American Samoa',
'AT': 'Austria',
'AU': 'Australia',
'AW': 'Aruba',
'AZ': 'Azerbaijan',
'BA': 'Bosnia and Herzegovina',
'BB': 'Barbados',
'BD': 'Bangladesh',
'BE': 'Belgium',
'BF': 'Burkina Faso',
'BG': 'Bulgaria',
'BH': 'Bahrain',
'BI': 'Burundi',
'BJ': 'Benin',
'BM': 'Bermuda',
'BN': 'Brunei Darussalam',
'BO': 'Bolivia',
'BR': 'Brazil',
'BS': 'Bahama',
'BT': 'Bhutan',
'BU': 'Burma (no longer exists)',
'BV': 'Bouvet Island',
'BW': 'Botswana',
'BY': 'Belarus',
'BZ': 'Belize',
'CA': 'Canada',
'CC': 'Cocos (Keeling) Islands',
'CF': 'Central African Republic',
'CG': 'Congo',
'CH': 'Switzerland',
'CI': 'Côte D\'ivoire (Ivory Coast)',
'CK': 'Cook Iislands',
'CL': 'Chile',
'CM': 'Cameroon',
'CN': 'China',
'CO': 'Colombia',
'CR': 'Costa Rica',
'CS': 'Czechoslovakia (no longer exists)',
'CU': 'Cuba',
'CV': 'Cape Verde',
'CX': 'Christmas Island',
'CY': 'Cyprus',
'CZ': 'Czech Republic',
'DD': 'German Democratic Republic (no longer exists)',
'DE': 'Germany',
'DJ': 'Djibouti',
'DK': 'Denmark',
'DM': 'Dominica',
'DO': 'Dominican Republic',
'DZ': 'Algeria',
'EC': 'Ecuador',
'EE': 'Estonia',
'EG': 'Egypt',
'EH': 'Western Sahara',
'ER': 'Eritrea',
'ES': 'Spain',
'ET': 'Ethiopia',
'FI': 'Finland',
'FJ': 'Fiji',
'FK': 'Falkland Islands (Malvinas)',
'FM': 'Micronesia',
'FO': 'Faroe Islands',
'FR': 'France',
'FX': 'France, Metropolitan',
'GA': 'Gabon',
'GB': 'United Kingdom (Great Britain)',
'GD': 'Grenada',
'GE': 'Georgia',
'GF': 'French Guiana',
'GH': 'Ghana',
'GI': 'Gibraltar',
'GL': 'Greenland',
'GM': 'Gambia',
'GN': 'Guinea',
'GP': 'Guadeloupe',
'GQ': 'Equatorial Guinea',
'GR': 'Greece',
'GS': 'South Georgia and the South Sandwich Islands',
'GT': 'Guatemala',
'GU': 'Guam',
'GW': 'Guinea-Bissau',
'GY': 'Guyana',
'HK': 'Hong Kong',
'HM': 'Heard & McDonald Islands',
'HN': 'Honduras',
'HR': 'Croatia',
'HT': 'Haiti',
'HU': 'Hungary',
'ID': 'Indonesia',
'IE': 'Ireland',
'IL': 'Israel',
'IN': 'India',
'IO': 'British Indian Ocean Territory',
'IQ': 'Iraq',
'IR': 'Islamic Republic of Iran',
'IS': 'Iceland',
'IT': 'Italy',
'JM': 'Jamaica',
'JO': 'Jordan',
'JP': 'Japan',
'KE': 'Kenya',
'KG': 'Kyrgyzstan',
'KH': 'Cambodia',
'KI': 'Kiribati',
'KM': 'Comoros',
'KN': 'St. Kitts and Nevis',
'KP': 'Korea, Democratic People\'s Republic of',
'KR': 'Korea, Republic of',
'KW': 'Kuwait',
'KY': 'Cayman Islands',
'KZ': 'Kazakhstan',
'LA': 'Lao People\'s Democratic Republic',
'LB': 'Lebanon',
'LC': 'Saint Lucia',
'LI': 'Liechtenstein',
'LK': 'Sri Lanka',
'LR': 'Liberia',
'LS': 'Lesotho',
'LT': 'Lithuania',
'LU': 'Luxembourg',
'LV': 'Latvia',
'LY': 'Libyan Arab Jamahiriya',
'MA': 'Morocco',
'MC': 'Monaco',
'MD': 'Moldova, Republic of',
'MG': 'Madagascar',
'MH': 'Marshall Islands',
'ML': 'Mali',
'MN': 'Mongolia',
'MM': 'Myanmar',
'MO': 'Macau',
'MP': 'Northern Mariana Islands',
'MQ': 'Martinique',
'MR': 'Mauritania',
'MS': 'Monserrat',
'MT': 'Malta',
'MU': 'Mauritius',
'MV': 'Maldives',
'MW': 'Malawi',
'MX': 'Mexico',
'MY': 'Malaysia',
'MZ': 'Mozambique',
'NA': 'Namibia',
'NC': 'New Caledonia',
'NE': 'Niger',
'NF': 'Norfolk Island',
'NG': 'Nigeria',
'NI': 'Nicaragua',
'NL': 'Netherlands',
'NO': 'Norway',
'NP': 'Nepal',
'NR': 'Nauru',
'NT': 'Neutral Zone (no longer exists)',
'NU': 'Niue',
'NZ': 'New Zealand',
'OM': 'Oman',
'PA': 'Panama',
'PE': 'Peru',
'PF': 'French Polynesia',
'PG': 'Papua New Guinea',
'PH': 'Philippines',
'PK': 'Pakistan',
'PL': 'Poland',
'PM': 'St. Pierre & Miquelon',
'PN': 'Pitcairn',
'PR': 'Puerto Rico',
'PT': 'Portugal',
'PW': 'Palau',
'PY': 'Paraguay',
'QA': 'Qatar',
'RE': 'Réunion',
'RO': 'Romania',
'RU': 'Russian Federation',
'RW': 'Rwanda',
'SA': 'Saudi Arabia',
'SB': 'Solomon Islands',
'SC': 'Seychelles',
'SD': 'Sudan',
'SE': 'Sweden',
'SG': 'Singapore',
'SH': 'St. Helena',
'SI': 'Slovenia',
'SJ': 'Svalbard & Jan Mayen Islands',
'SK': 'Slovakia',
'SL': 'Sierra Leone',
'SM': 'San Marino',
'SN': 'Senegal',
'SO': 'Somalia',
'SR': 'Suriname',
'ST': 'Sao Tome & Principe',
'SU': 'Union of Soviet Socialist Republics (no longer exists)',
'SV': 'El Salvador',
'SY': 'Syrian Arab Republic',
'SZ': 'Swaziland',
'TC': 'Turks & Caicos Islands',
'TD': 'Chad',
'TF': 'French Southern Territories',
'TG': 'Togo',
'TH': 'Thailand',
'TJ': 'Tajikistan',
'TK': 'Tokelau',
'TM': 'Turkmenistan',
'TN': 'Tunisia',
'TO': 'Tonga',
'TP': 'East Timor',
'TR': 'Turkey',
'TT': 'Trinidad & Tobago',
'TV': 'Tuvalu',
'TW': 'Taiwan, Province of China',
'TZ': 'Tanzania, United Republic of',
'UA': 'Ukraine',
'UG': 'Uganda',
'UM': 'United States Minor Outlying Islands',
'US': 'United States of America',
'UY': 'Uruguay',
'UZ': 'Uzbekistan',
'VA': 'Vatican City State (Holy See)',
'VC': 'St. Vincent & the Grenadines',
'VE': 'Venezuela',
'VG': 'British Virgin Islands',
'VI': 'United States Virgin Islands',
'VN': 'Viet Nam',
'VU': 'Vanuatu',
'WF': 'Wallis & Futuna Islands',
'WS': 'Samoa',
'YD': 'Democratic Yemen (no longer exists)',
'YE': 'Yemen',
'YT': 'Mayotte',
'YU': 'Yugoslavia',
'ZA': 'South Africa',
'ZM': 'Zambia',
'ZR': 'Zaire',
'ZW': 'Zimbabwe',
'ZZ': 'Unknown or unspecified country',
}
# Three letter codes
#https://en.wikipedia.org/wiki/ISO_3166-1_alpha-3#Uses_and_applications
alpha3 = """ABW Aruba
AFG Afghanistan
AGO Angola
AIA Anguilla
ALA Åland Islands
ALB Albania
AND Andorra
ARE United Arab Emirates
ARG Argentina
ARM Armenia
ASM American Samoa
ATA Antarctica
ATF French Southern Territories
ATG Antigua and Barbuda
AUS Australia
AUT Austria
AZE Azerbaijan
BDI Burundi
BEL Belgium
BEN Benin
BES Bonaire, Sint Eustatius and Saba
BFA Burkina Faso
BGD Bangladesh
BGR Bulgaria
BHR Bahrain
BHS Bahamas
BIH Bosnia and Herzegovina
BLM Saint Barthélemy
BLR Belarus
BLZ Belize
BMU Bermuda
BOL Bolivia (Plurinational State of)
BRA Brazil
BRB Barbados
BRN Brunei Darussalam
BTN Bhutan
BVT Bouvet Island
BWA Botswana
CAF Central African Republic
CAN Canada
CCK Cocos (Keeling) Islands
CHE Switzerland
CHL Chile
CHN China
CIV Côte d'Ivoire
CMR Cameroon
COD Congo, Democratic Republic of the
COG Congo
COK Cook Islands
COL Colombia
COM Comoros
CPV Cabo Verde
CRI Costa Rica
CUB Cuba
CUW Curaçao
CXR Christmas Island
CYM Cayman Islands
CYP Cyprus
CZE Czechia
DEU Germany
DJI Djibouti
DMA Dominica
DNK Denmark
DOM Dominican Republic
DZA Algeria
ECU Ecuador
EGY Egypt
ERI Eritrea
ESH Western Sahara
ESP Spain
EST Estonia
ETH Ethiopia
FIN Finland
FJI Fiji
FLK Falkland Islands (Malvinas)
FRA France
FRO Faroe Islands
FSM Micronesia (Federated States of)
GAB Gabon
GBR United Kingdom of Great Britain and Northern Ireland
GEO Georgia
GGY Guernsey
GHA Ghana
GIB Gibraltar
GIN Guinea
GLP Guadeloupe
GMB Gambia
GNB Guinea-Bissau
GNQ Equatorial Guinea
GRC Greece
GRD Grenada
GRL Greenland
GTM Guatemala
GUF French Guiana
GUM Guam
GUY Guyana
HKG Hong Kong
HMD Heard Island and McDonald Islands
HND Honduras
HRV Croatia
HTI Haiti
HUN Hungary
IDN Indonesia
IMN Isle of Man
IND India
IOT British Indian Ocean Territory
IRL Ireland
IRN Iran (Islamic Republic of)
IRQ Iraq
ISL Iceland
ISR Israel
ITA Italy
JAM Jamaica
JEY Jersey
JOR Jordan
JPN Japan
KAZ Kazakhstan
KEN Kenya
KGZ Kyrgyzstan
KHM Cambodia
KIR Kiribati
KNA Saint Kitts and Nevis
KOR Korea, Republic of
KWT Kuwait
LAO Lao People's Democratic Republic
LBN Lebanon
LBR Liberia
LBY Libya
LCA Saint Lucia
LIE Liechtenstein
LKA Sri Lanka
LSO Lesotho
LTU Lithuania
LUX Luxembourg
LVA Latvia
MAC Macao
MAF Saint Martin (French part)
MAR Morocco
MCO Monaco
MDA Moldova, Republic of
MDG Madagascar
MDV Maldives
MEX Mexico
MHL Marshall Islands
MKD North Macedonia
MLI Mali
MLT Malta
MMR Myanmar
MNE Montenegro
MNG Mongolia
MNP Northern Mariana Islands
MOZ Mozambique
MRT Mauritania
MSR Montserrat
MTQ Martinique
MUS Mauritius
MWI Malawi
MYS Malaysia
MYT Mayotte
NAM Namibia
NCL New Caledonia
NER Niger
NFK Norfolk Island
NGA Nigeria
NIC Nicaragua
NIU Niue
NLD Netherlands
NOR Norway
NPL Nepal
NRU Nauru
NZL New Zealand
OMN Oman
PAK Pakistan
PAN Panama
PCN Pitcairn
PER Peru
PHL Philippines
PLW Palau
PNG Papua New Guinea
POL Poland
PRI Puerto Rico
PRK Korea (Democratic People's Republic of)
PRT Portugal
PRY Paraguay
PSE Palestine, State of
PYF French Polynesia
QAT Qatar
REU Réunion
ROU Romania
RUS Russian Federation
RWA Rwanda
SAU Saudi Arabia
SDN Sudan
SEN Senegal
SGP Singapore
SGS South Georgia and the South Sandwich Islands
SHN Saint Helena, Ascension and Tristan da Cunha
SJM Svalbard and Jan Mayen
SLB Solomon Islands
SLE Sierra Leone
SLV El Salvador
SMR San Marino
SOM Somalia
SPM Saint Pierre and Miquelon
SRB Serbia
SSD South Sudan
STP Sao Tome and Principe
SUR Suriname
SVK Slovakia
SVN Slovenia
SWE Sweden
SWZ Eswatini
SXM Sint Maarten (Dutch part)
SYC Seychelles
SYR Syrian Arab Republic
TCA Turks and Caicos Islands
TCD Chad
TGO Togo
THA Thailand
TJK Tajikistan
TKL Tokelau
TKM Turkmenistan
TLS Timor-Leste
TON Tonga
TTO Trinidad and Tobago
TUN Tunisia
TUR Turkey
TUV Tuvalu
TWN Taiwan, Province of China
TZA Tanzania, United Republic of
UGA Uganda
UKR Ukraine
UMI United States Minor Outlying Islands
URY Uruguay
USA United States of America
UZB Uzbekistan
VAT Holy See
VCT Saint Vincent and the Grenadines
VEN Venezuela (Bolivarian Republic of)
VGB Virgin Islands (British)
VIR Virgin Islands (U.S.)
VNM Viet Nam
VUT Vanuatu
WLF Wallis and Futuna
WSM Samoa
YEM Yemen
ZAF South Africa
ZMB Zambia
ZWE Zimbabwe"""
# Convert to dictionary
alpha3 = dict(tuple(re.split(r" {2,}", s)) for s in alpha3.split('\n'))
# List of World Cities & Country
# cities https://pkgstore.datahub.io/core/world-cities/world-cities_csv/data/6cc66692f0e82b18216a48443b6b95da/world-cities_csv.csv
# Online CSV File
import csv
import urllib.request
import io
def csv_import(url):
url_open = urllib.request.urlopen(url)
csvfile = csv.DictReader(io.StringIO(url_open.read().decode('utf-8')), delimiter=',')
return csvfile
url = 'https://pkgstore.datahub.io/core/world-cities/world-cities_csv/data/6cc66692f0e82b18216a48443b6b95da/world-cities_csv.csv'
cities = csv_import(url)
Test
Excel File (Input)
country city
u.s.
DZ
AS
co Longmont
co Bogota
AL
AL Huntsville
usa
AFG
BLR Minsk
AUS
united states
Korea seoul
Korea Pyongyang
Test Code
df = pd.read_excel('country_test.xlsx') # Load Excel File
df.fillna('', inplace=True)
# Get name of country based upon country and city
df['country_'] = df.apply(lambda row: lookup(row['country'], row['city']), axis = 1)
Resulting Dataframe
country city country_
0 u.s. United States of America
1 DZ Algeria
2 AS American Samoa
3 co Longmont United States
4 co Bogota Colombia
5 AL Albania
6 AL Huntsville United States
7 usa United States of America
8 AFG Afghanistan
9 BLR Minsk Belarus
10 AUS Australia
11 united states United States of America
12 Korea seoul South Korea
13 Korea Pyongyang North Korea