在Python中使用条件条件

Question

我有一个 python 函数，其中包含一个 if 语句来检查某些内容。

def my_func(a, b, c):
  if a < b and b < c:
    #do complicated stuff

我想修改该函数，以便调用者可以通过传入布尔值来确定是否执行 if 语句检查。

def my_func(a, b, c, perform_check=True):

我试图弄清楚如何使条件仅有时被调用，或在其他时候被跳过。

Answer 1

我想你需要的是这样的东西：

if include_already_seen or not data[person].get(item, 0):

Answer 2

def find_recommendations(person, using=pearson_correlation, data=critics, include_already_seen=True):
  totals  = {}
  sim_sum = {}

  for critic in critics:
    if critic != person:
      similarity_score = using(data, person, critic)
      print "the similarity score between %s and %s is %d" % (person, critic, similarity_score)
      if similarity_score <= 0: continue    # ignore similarity_scores below 0

      for item in data[critic]:

        if include_already_seen or (item not in data[person] or data[person][item] == 0):
          totals.setdefault(item,0)
          totals[item] += data[critic][item] * similarity_score

          sim_sum.setdefault(item,0)
          sim_sum[item] += similarity_score

  #create the normalized list
  rankings = [ (total/sim_sum[item],item) for item, total in totals.items()]

  rankings_sorted = sorted(rankings)
  rankings_sorted.reverse()
  return rankings_sorted