2019-02-21 python_list

append()

cities = []
cities.append('Albuquerque')

open and read

a =open("story.txt")
print(a)

<_io.TextIOWrapper name='story.txt' mode='r' encoding='cp936'>

a = open('story.txt','r',encoding='utf-8')

a

<_io.TextIOWrapper name='story.txt' mode='r' encoding='utf-8'>

print (a.read())

test by shishuai

sqlit

data = open('crime_rates.csv').read()

print(data)

Albuquerque,749
Anaheim,371
Anchorage,828
Arlington,503
Atlanta,1379
Aurora,425
Austin,408
Bakersfield,542
Baltimore,1405
Boston,835
Buffalo,1288
Charlotte-Mecklenburg,647
Cincinnati,974
Cleveland,1383
Colorado Springs,455
Corpus Christi,658
Dallas,675
Denver,615
Detroit,2122
El Paso,423
Fort Wayne,362
Fort Worth,587
Fresno,543
Greensboro,563
Henderson,168
Houston,992
Indianapolis,1185
Jacksonville,617
Jersey City,734
Kansas City,1263
Las Vegas,784
Lexington,352
Lincoln,397
Long Beach,575
Los Angeles,481
Louisville Metro,598
Memphis,1750
Mesa,399
Miami,1172
Milwaukee,1294
Minneapolis,992
Mobile,522
Nashville,1216
New Orleans,815
New York,639
Newark,1154
Oakland,1993
Oklahoma City,919
Omaha,594
Philadelphia,1160
Phoenix,636
Pittsburgh,752
Plano,130
Portland,517
Raleigh,423
Riverside,443
Sacramento,738
San Antonio,503
San Diego,413
San Francisco,704
San Jose,363
Santa Ana,401
Seattle,597
St. Louis,1776
St. Paul,722
Stockton,1548
Tampa,616
Toledo,1171
Tucson,724
Tulsa,990
Virginia Beach,169
Washington,1177
Wichita,742

rows = data.split('\n')

print(rows[:5])

['Albuquerque,749', 'Anaheim,371', 'Anchorage,828', 'Arlington,503', 'Atlanta,1379']

type(rows)

list

type(data)

str

final_data  = []
for row in rows:
    final_data.append(row.split(','))
print(final_data[:3])

[['Albuquerque', '749'], ['Anaheim', '371'], ['Anchorage', '828']]

cities_list = []
for element in final_data:
    cities_list.append(element[0])
print(cities_list[:5])

['Albuquerque', 'Anaheim', 'Anchorage', 'Arlington', 'Atlanta']

int_crime_rates = []
for element in final_data:
    int_crime_rates.append(int(element[1]))
print(int_crime_rates)

[749, 371, 828, 503, 1379, 425, 408, 542, 1405, 835, 1288, 647, 974, 1383, 455, 658, 675, 615, 2122, 423, 362, 587, 543, 563, 168, 992, 1185, 617, 734, 1263, 784, 352, 397, 575, 481, 598, 1750, 399, 1172, 1294, 992, 522, 1216, 815, 639, 1154, 1993, 919, 594, 1160, 636, 752, 130, 517, 423, 443, 738, 503, 413, 704, 363, 401, 597, 1776, 722, 1548, 616, 1171, 724, 990, 169, 1177, 742]