我自学 Python通过麻省理工学院的OCW 6.00。 （所以请不要评论“你不应该要求做作业问题”......我甚至不在麻省理工学院，就像我希望的那样。）我现在被困在{ {3}}
以下是ps5.py的<相关部分：
def update_hand(hand, word):
"""
Uses up all the letters in the given word and returns
the new hand. Does not modify hand.
word: string
hand: dictionary (string -> int)
"""
hand = hand.copy()
for char in word:
hand[char] = hand.get(char,0)-1
return hand
def is_valid_word(word, hand, word_list):
"""
Returns True if word is in the word_list and is entirely
composed of letters in the hand. Otherwise, returns False.
Does not mutate hand or word_list.
word: string
hand: dictionary (string -> int)
word_list: list of lowercase strings
"""
if word not in word_list:
return False
after = update_hand(hand.copy(),word)
for char in after:
if after[char] < 0:
return False
return True
我运行了代码并返回了正确的结果。
Loading word list from file...
83667 words loaded.
play_game not implemented.
play_hand not implemented.
>>> word = "python"
>>> hand = {'h':1,'n':1,'o':1,'p':1,'t':1,'y':1}
>>> word_list = load_words()
Loading word list from file...
83667 words loaded.
>>> is_valid_word(word, hand, word_list)
True
>>> word = "cobra"
>>> is_valid_word(word, hand, word_list)
False
>>> hand
{'h': 1,'n': 1,'o': 1,'p': 1,'t': 1,'y': 1}
我的问题是，当is_valid_word函数导入test_ps5.py时，它似乎只是为所有内容返回False，这意味着它会失败一半的测试用例。
以下是test_ps5.py的<相关部分：
from ps5 import *
def test_is_valid_word(word_list):
"""
Unit test for is_valid_word
"""
failure=False
# test 1
word = "hello"
hand = {'h':1, 'e':1, 'l':2, 'o':1}
if not is_valid_word(word, hand, word_list):
print "FAILURE: test_is_valid_word()"
print "\tExpected True, but got False for word: '" + word + "' and hand:", hand
failure = True
# test 2 passes
# test 3
hand = {'n': 1, 'h': 1, 'o': 1, 'y': 1, 'd':1, 'w':1, 'e': 2}
word = "honey"
if not is_valid_word(word, hand, word_list):
print "FAILURE: test_is_valid_word()"
print "\tExpected True, but got False for word: '"+ word +"' and hand:", hand
failure = True
# test 4 passes
# test 5
hand = {'e':1, 'v':2, 'n':1, 'i':1, 'l':2}
word = "evil"
if not is_valid_word(word, hand, word_list):
print "FAILURE: test_is_valid_word()"
print "\tExpected True, but got False for word: '" + word + "' and hand:", hand
failure = True
# test 6 passes
if not failure:
print "SUCCESS: test_is_valid_word()"
word_list = load_words()
这是我运行代码时的结果：
Loading word list from file...
83667 words loaded.
----------------------------------------------------------------------
Testing get_word_score...
SUCCESS: test_get_word_score()
----------------------------------------------------------------------
Testing update_hand...
SUCCESS: test_update_hand()
----------------------------------------------------------------------
Testing is_valid_word...
FAILURE: test_is_valid_word()
Expected True, but got False for word: 'hello' and hand: {'h': 1, 'e': 1, 'l': 2, 'o': 1}
FAILURE: test_is_valid_word()
Expected True, but got False for word: 'honey' and hand: {'e': 2, 'd': 1, 'h': 1, 'o': 1, 'n': 1, 'w': 1, 'y': 1}
FAILURE: test_is_valid_word()
Expected True, but got False for word: 'evil' and hand: {'i': 1, 'n': 1, 'e': 1, 'l': 2, 'v': 2}
----------------------------------------------------------------------
All done!
我无法理解造成问题的原因和原因。
答案 0 :(得分：0)
问题不在您发布的代码中。这很好用：
ps5.py：
def update_hand(hand, word):
"""
Uses up all the letters in the given word and returns
the new hand. Does not modify hand.
word: string
hand: dictionary (string -> int)
"""
hand = hand.copy()
for char in word:
hand[char] = hand.get(char,0)-1
return hand
def is_valid_word(word, hand, word_list):
"""
Returns True if word is in the word_list and is entirely
composed of letters in the hand. Otherwise, returns False.
Does not mutate hand or word_list.
word: string
hand: dictionary (string -> int)
word_list: list of lowercase strings
"""
if word not in word_list:
return False
after = update_hand(hand.copy(),word)
for char in after:
if after[char] < 0:
return False
return True
words.py：
#!/usr/bin/env python
from ps5 import *
def test_is_valid_word(word_list):
"""
Unit test for is_valid_word
"""
failure=False
# test 1
word = "hello"
hand = {'h':1, 'e':1, 'l':2, 'o':1}
if not is_valid_word(word, hand, word_list):
print "FAILURE: test_is_valid_word()"
print "\tExpected True, but got False for word: '" + word + "' and hand:", hand
failure = True
# test 2 passes
# test 3
hand = {'n': 1, 'h': 1, 'o': 1, 'y': 1, 'd':1, 'w':1, 'e': 2}
word = "honey"
if not is_valid_word(word, hand, word_list):
print "FAILURE: test_is_valid_word()"
print "\tExpected True, but got False for word: '"+ word +"' and hand:", hand
failure = True
# test 4 passes
# test 5
hand = {'e':1, 'v':2, 'n':1, 'i':1, 'l':2}
word = "evil"
if not is_valid_word(word, hand, word_list):
print "FAILURE: test_is_valid_word()"
print "\tExpected True, but got False for word: '" + word + "' and hand:", hand
failure = True
# test 6 passes
if not failure:
print "SUCCESS: test_is_valid_word()"
def main():
wordlist = ['honey', 'evil', 'python', 'dogs', 'weasels', 'hello']
test_is_valid_word(wordlist)
if __name__ == '__main__':
main()
将两个文件放在同一目录中，输出结果为：
paul@local:~/Documents/src/sandbox$ ./words.py
SUCCESS: test_is_valid_word()
paul@local:~/Documents/src/sandbox$
你有几次暗示你遗漏了很多不相关的＆＃34;码。除了从文件加载单词列表之外，此问题似乎不需要该代码。问题必须存在于您未显示的代码中。由于这个问题似乎并不需要，我建议（a）全部摆脱它; （b）逐个摆脱它，直到你的问题得到解决，然后逐步添加并定期测试，这样你就可以确切地看到代码会导致它破坏;或者（c）在当前代码中的战略位置插入大量print语句，这样您就可以确切地知道它失败的地点和原因，这将为您提供有关进展情况的线索on并帮助您隔离导致问题的代码位。
你也没有显示你如何调用test_is_valid_word()，所以这可能是一个简单的问题。
from something import *通常也是一个坏主意，有时会导致名称空间污染导致的神秘问题。请尝试from ps5 import update_hand, is_valid_word，看看是否有帮助。
没有剩下的代码（无论如何，这似乎都不相关），你是唯一可以做这些事情的人。