Python学习笔记之lambda表达式用法详解

def multiply(x, y):
  return x * y

double = lambda x, y: x * y

numbers = [
        [34, 63, 88, 71, 29],
        [90, 78, 51, 27, 45],
        [63, 37, 85, 46, 22],
        [51, 22, 34, 11, 18]
      ]
def mean(num_list):
  return sum(num_list) / len(num_list)
averages = list(map(mean, numbers))
print(averages)

numbers = [
        [34, 63, 88, 71, 29],
        [90, 78, 51, 27, 45],
        [63, 37, 85, 46, 22],
        [51, 22, 34, 11, 18]
      ]
averages = list(map(lambda x: sum(x) / len(x), numbers))
print(averages) # [57.0, 58.2, 50.6, 27.2]

cities = ["New York City", "Los Angeles", "Chicago", "Mountain View", "Denver", "Boston"]
def is_short(name):
  return len(name) < 10
short_cities = list(filter(is_short, cities))
print(short_cities)

cities = ["New York City", "Los Angeles", "Chicago", "Mountain View", "Denver", "Boston"]
short_cities = list(filter(lambda n: len(n) < 10, cities))
print(short_cities) # ['Chicago', 'Denver', 'Boston']