While-Schleifen werden im Skript unerwartet beendet.

Question

Ich habe gerade angefangen, Python vor zwei Monaten zu lernen. Noch ein Anfänger, aber ich komme aus einem soliden C-Hintergrund. Ich mache vielleicht keine Dinge auf "Python" Weise, da C so stark in mir verwurzelt ist, aber ich habe mein Skript funktioniert. Allerdings habe ich gerade eine while-Schleife hinzugefügt, so dass ich es mehrmals ausführen und auf Benutzeranforderung beenden kann. Die while-Schleife wird jedoch unabhängig von der Eingabe beendet. Ziemlich sicher, dass meine Einrückung korrekt ist. Hier ist das ganze Skript (mit meinem API-Schlüssel entfernt). Es ist die sehr außerhalb Schleife, die während beendet == 0:

#!/usr/bin/env python3 

import sys 
import requests 
import json 
import time 

appid = {'key': 'xxxxxxxxxxxxxxx'} 
kingston = {'city': "/Canada/Kingston.json", 'city_str': "Kingston, Ontario"} 
ottawa = {'city': "/Canada/Ottawa.json", 'city_str': "Ottawa, Ontario"} 
toronto = {'city': "/Canada/Toronto.json", 'city_str': "Toronto, Ontario"} 
vancouver = {'city': "/Canada/Vancouver.json", 'city_str': "Vancouver, British Columbia"} 
sydney = {'city': "/Australia/Sydney.json", 'city_str': "Sydney, Australia"} 
wellington = {'city': "/zmw:00000.1.93436.json", 'city_str': "Wellington, New Zealand"} 
london = {'city': "/zmw:00000.1.03772.json", 'city_str': "London, UK"} 
bergen = {'city': "/zmw:00000.1.01317.json", 'city_str': "Bergen, Norway"} 

def cityquery(query): 
     searchresult = requests.get("http://autocomplete.wunderground.com/aq", params={'query': query}) 
     results = json.loads(searchresult.text) 
     for index, x in enumerate(results['RESULTS'], start=1): 
       print(index, x['name']) 
     selection = input("Please select a number from the list:") 
     return {'city': results['RESULTS'][int(selection) - 1]['l'] + ".json", 'city_str': results['RESULTS'][int(selection) - 1]['name']} 

def getWeather(): 
     finished = 0 
     while finished == 0: 
       selected = 0 
       print("Please choose a city, or enter s to search by city name:") 
       print("\t1)", toronto['city_str']) 
       print("\t2)", sydney['city_str']) 
       print("\t3)", london['city_str']) 
       print("\t4)", vancouver['city_str']) 
       print("\t5)", ottawa['city_str']) 
       print("\t6)", kingston['city_str']) 
       print("\t7)", wellington['city_str']) 
       print("\t8)", bergen['city_str']) 
       while selected == 0: 
         citynumber = input("Enter a city number or s: ") 
         if citynumber == '1': 
           current_city = toronto 
           selected = 1 
         elif citynumber == '2': 
           current_city = sydney 
           selected = 1 
         elif citynumber == '3': 
           current_city = london 
           selected = 1 
         elif citynumber == '4': 
           current_city = vancouver 
           selected = 1 
         elif citynumber == '5': 
           current_city = ottawa 
           selected = 1 
         elif citynumber == '6': 
           current_city = kingston 
           selected = 1 
         elif citynumber == '7': 
           current_city = wellington 
           selected = 1 
         elif citynumber == '8': 
           current_city = bergen 
           selected = 1 
         elif citynumber == 's': 
           searchterm = input("Please type the first few characters of a city name: ") 
           current_city = cityquery(searchterm) 
           selected = 1 
         else: 
           print("Invalid entry!") 


       current_time = time.localtime() 
       print("The current time is", str('{:02d}'.format(current_time[3])) + ":" + str('{:02d}'.format(current_time[4])) + ":" + str('{:02d}'.format(current_time[5]))) 
       print("Forecast for", current_city['city_str']) 

       #Current conditions 
       print("Getting current conditions...") 
       page = requests.get("http://api.wunderground.com/api/" + str(appid['key']) + "/conditions/q/" + current_city['city']) 
       values = json.loads(page.text) 
       # DEBUG print(page.text) 
       # DEBUG print(current_city) 
       temp = float(values['current_observation']['temp_c']) 
       if values['current_observation']['windchill_c'] == 'NA': 
         temp_wc = temp 
       else: 
         temp_wc = float(values['current_observation']['windchill_c']) 
       print("The temperature in", current_city['city_str'], "is currently", str('{:.2f}'.format(temp)) + "C feeling like", str('{:.2f}'.format(temp_wc)) + "C") 
       pressure_in = float(values['current_observation']['pressure_in']) 
       pressure_kp = float(values['current_observation']['pressure_mb'])/10.0 
       print("The barometric pressure is", str('{:.2f}'.format(pressure_in)), "inches of mercury or", str('{:.1f}'.format(pressure_kp)), "kilopascals.") 
       wind_speed = float(values['current_observation']['wind_kph']) 
       wind_gust = float(values['current_observation']['wind_gust_kph']) 
       wind_dir = str(values['current_observation']['wind_dir']) 
       if wind_gust == 0: 
         print("The wind is", str('{:.2f}'.format(wind_speed)), "km/h from the", wind_dir) 
       else: 
         print("The wind is", str('{:.2f}'.format(wind_speed)), "km/h, gusting to", str('{:.2f}'.format(wind_gust)), "km/h from the", wind_dir) 

       #Forecast 
       print("Getting forecast...") 
       page = requests.get("http://api.wunderground.com/api/" + str(appid['key']) + "/forecast/q" + current_city['city']) 
       values = json.loads(page.text) 
       for x in [0, 1, 2, 3, 4, 5]: 
         print("Forecast for", values['forecast']['txt_forecast']['forecastday'][x]['title'], ":", values['forecast']['txt_forecast']['forecastday'][x]['fcttext_metric']) 

       waiting = 0 # loop until valid input 
       while waiting == 0: 
         exit = input("Press x to exit or c to check again...") 
         if exit == 'x' or 'X': 
           finished = 1 
           waiting = 1 
         elif exit == 'c' or 'C': 
           finished = 0 
           waiting = 1 
         else: 
           finished = 0 
           waiting = 0 

if __name__ == "__main__": 
    getWeather() 

Answer 1

Es ist ein Fehler in Zeile 110 (if elif Block innerhalb while waiting). Korrekte Aussage wäre:

if exit == 'x' or exit == 'X' 

Ihre Aussage liest if exit == 'x' or 'X', die falsch ist. Es wird 10 mit x verglichen, aber nicht mit X. Was Sie schreiben möchten, ist , wenn Exit gleich x ist oder Exit gleich X, aber Sie haben für codiert entweder Exit ist gleich X oder X ist True. Nun ist 'X' immer wahr und es ist unabhängig von Ihrer Eingabe (weil Sie es nicht mit einer Variablen vergleichen) und daher endet die Schleife unabhängig von der Eingabe. Derselbe Fehler ist in elif und else Block.

Dies ist sehr ähnlich wie C