此程序旨在向用户询问州开始的一个或多个字母。当它有输入时，它会显示该状态的信息，包括来自网络的人口和平方公里面积。当用户输入有多个结果时，我需要该程序为总体人口和面积提供总数。即。用户类型：c，并获得加利福尼亚州，科罗拉多州，康涅狄格州等。我只需要在显示的所有结果结束时打印一次总计。我试图在定义find_starts_with中放置我想要它做的但是没有运气。
这可能是一个简单的解决方法，但我仍然相对较新的python，并会感谢任何和所有的帮助。
#p6 states
#reads text file from the web
state_list=[]
import urllib.request
def read_file(url):
""" reads the url and returns a unicode txt file"""
with urllib.request.urlopen(url) as webpage: #opens the webpage
for line in webpage:
line= line.strip()
line= line.decode('utf-8')#unicode
if line [0] != "#":
item_list =line.split(',')#splits list at comma
state= item_list[0].lower()
capital = item_list[1].lower()
area=int(item_list[2])
pop= float(item_list[3])
state_list.append([state, capital, area, pop])
return state_list
#end if
#end for
#end with
#----------------------------------------------------------------
def find_starts_with(start_letters, state_list):
""" searches text file to find a state beginning with the letters entered"""
print()
found= False
n_to_match=len(state_to_find)
for item_list in state_list:
state= item_list[0].lower()
if state_to_find == state[0:n_to_match]:
total_pop = 0.0
total_area = 0
if state_to_find == state[0:n_to_match]:
print_state=state.title()
capital = item_list[1]
print_capital = capital.title()
area = int(item_list[2])
print_area = format(area, '10,d') # 10 spaces, show commas
pop = float(item_list[3])
print_pop = format(pop, '10,.1f')
found= True
for item in float(item_list[3]):
total_pop += pop
for item in int(item_list[2]):
total_area += area
print(print_state, "capital: ", print_capital, "\n",
print_area, "sq km\n ",
print_pop, "million people\n")
print("total area", total_area, "Total population ", total_pop)
if not found:
print("don't you know how to spell your states correctly? ")
return None
#-----------------------------------------------------------------------
#-----------------------------------------------------------------------
url = "http://www.cs.uoregon.edu/classes/15F/cis122/data/state_data.txt"
state_list= read_file(url)
request=input("type the first few letters of a states name or type q to quit ")
while request != 'q':
state_to_find=request
state_to_find= state_to_find. lower()
find_starts_with(state_to_find, state_list)
print ("total area: ", total_area, "\n Total population: ", total_pop)
request= input("type the first few letters of a states name or type q to quit ")
if request=='q':
print("have a nice day")
答案 0 :(得分：0)
for item in float(item_list[3]):
total_pop += pop
for item in int(item_list[2]):
total_area += area
在这段代码中，你试图迭代一个浮点数和一个int，这是不允许的，因为你只能迭代列表，字典等。你也试图打印total_area和total_pop这些是局部变量函数外的函数“find_starts_with”。如果要在函数外部打印它们，请将它们声明为全局或返回值。
以下是更正后的代码：
#p6 states
#reads text file from the web
state_list=[]
import urllib.request
def read_file(url):
""" reads the url and returns a unicode txt file"""
with urllib.request.urlopen(url) as webpage: #opens the webpage
for line in webpage:
line= line.strip()
line= line.decode('utf-8')#unicode
if line [0] != "#":
item_list =line.split(',')#splits list at comma
state= item_list[0].lower()
capital = item_list[1].lower()
area=int(item_list[2])
pop= float(item_list[3])
state_list.append([state, capital, area, pop])
#print(state_list)
return state_list
#end if
#end for
#end with
#----------------------------------------------------------------
def find_starts_with(start_letters, state_list):
""" searches text file to find a state beginning with the letters entered"""
print()
found= False
n_to_match=len(state_to_find)
total_pop = 0
total_area = 0
for item_list in state_list:
state= item_list[0].lower()
if state_to_find == state[0:n_to_match]:
total_pop = 0.0
total_area = 0
if state_to_find == state[0:n_to_match]:
print_state=state.title()
capital = item_list[1]
print_capital = capital.title()
area = int(item_list[2])
print_area = format(area, '10,d') # 10 spaces, show commas
pop = float(item_list[3])
print_pop = format(pop, '10,.1f')
found= True
total_pop += pop
total_area += area
print(print_state, "capital: ", print_capital, "\n",
print_area, "sq km\n ",
print_pop, "million people\n")
#print("total area", total_area, "Total population ", total_pop)
if not found:
print("don't you know how to spell your states correctly? ")
return total_pop,total_area
#-----------------------------------------------------------------------
#-----------------------------------------------------------------------
url = "http://www.cs.uoregon.edu/classes/15F/cis122/data/state_data.txt"
state_list= read_file(url)
request=input("type the first few letters of a states name or type q to quit ")
while request != 'q':
state_to_find=request
state_to_find= state_to_find. lower()
total_pop,total_area=find_starts_with(state_to_find, state_list)
print ("total area: ", total_area, "\n Total population: ", total_pop)
request= input("type the first few letters of a states name or type q to quit ")
if request=='q':
print("have a nice day")
输出：
type the first few letters of a states name or type q to quit c
California capital: Sacramento
423,970 sq km
38.3 million people
Colorado capital: Denver
269,601 sq km
5.2 million people
Connecticut capital: Hartford
14,357 sq km
3.6 million people
total area: 14357
Total population: 3.6
type the first few letters of a states name or type q to quit cali
California capital: Sacramento
423,970 sq km
38.3 million people
total area: 423970
Total population: 38.3
type the first few letters of a states name or type q to quit q
have a nice day