在python函数中如何传递要过滤的可选参数

Question

如何将可选参数传递给用户定义的函数，而调用该参数时，它将过滤原始数据，而忽略该参数，则不过滤原始数据

import spacy
from collections import Counter
nlp = spacy.load('en')
txt=“””Though the disease was eradicated decades ago, national security experts fear that stocks of the virus in labs could be released as a bioweapon.”””
doc = nlp(txt)

def common_pos(doc, n, pos):
  words =  [token.lemma_ for token in doc if token.is_stop != True and token.is_punct != True and token.pos_ == pos]
  word_freq = Counter(words)
  common_words =word_freq.most_common(n)
  print(common_words)

此处pos是可选参数。理想的行为是，如果我不通过pos，则显示最常见的单词，而如果我通过“ VERB”作为pos，则显示最常见的动词。

如何使它成为可选参数？谢谢

Answer 1

def common_pos(doc, n, pos=None):
  words = [
    token.lemma_
    for token
    in doc
    if (
      token.is_stop != True and
      token.is_punct != True and
      (not pos or token.pos_ == pos)
    )
  ]
  word_freq = Counter(words)
  common_words =word_freq.most_common(n)
  print(common_words)

如果确实存在，则基本上仅按pos进行过滤。

Answer 2

您需要为其分配一个默认值，它会自动变为可选值。

您可能需要对逻辑进行一些修改，但以功能为例

def common_pos(doc, n, pos='VERB'):

您愿意拿走pos，但如果不付出，它将变成'VERB'。