filter
1、循环帮你调用函数
2、帮你过滤你传入的参数,函数的结果返回的是true那就保存,返回false就不要,且返回的也是迭代器
备注:迭代器用完一个就扔掉一个,直到全部用完,且需要一个list接一下,否则返回的是对象
格式: filter(function, iterable)
function -- 判断函数
iterable -- 可迭代对象
def add(a): return a%2==0 print(list(filter(add,[1,2,3,4]))) /Library/Frameworks/Python.framework/Versions/3.7/bin/python3.7 /Users/dongyf/Documents/python/besttest_study/cnz/ycc/a.py [2, 4]
filter与lambda结合使用
stu_score = {'xiaobai':50,'xiaohei':30,'xiaolan':80,'xiaojun':100, 'xiaoming':60} result=filter(lambda score:score>60,stu_score.values()) print(list(result)) /Library/Frameworks/Python.framework/Versions/3.7/bin/python3.7 /Users/dongyf/Documents/python/besttest_study/cnz/ycc/a.py [80, 100]