实操一:
1、用map来处理字符串列表啊,把列表中所有人都变成sb,比方alex_sb
name=[‘alex‘,‘wupeiqi‘,‘yuanhao‘]
name=[‘alex‘,‘wupeiqi‘,‘yuanhao‘] m = map(lambda name:name+"_SB",name) print(list(m)) ------------输出结果------------------ [‘alex_SB‘, ‘wupeiqi_SB‘, ‘yuanhao_SB‘]
2、用map来处理下述l,然后用list得到一个新的列表,列表中每个人的名字都是sb结尾
l=[{‘name‘:‘alex‘},{‘name‘:‘egon‘}]
l=[{‘name‘:‘alex‘},{‘name‘:‘egon‘}] m = map(lambda l : l["name"]+"_SB",l) print(list(m)) ----------输出结果----------- [‘alex_SB‘, ‘egon_SB‘]
实操二:
用filter来处理,得到股票价格大于20的股票名字
shares={
‘IBM‘:36.6,
‘Lenovo‘:23.2,
‘oldboy‘:21.2,
‘ocean‘:10.2,
}
f = filter(lambda d:shares[d]>20,shares) for i in f: print(i) ----------输出结果------------ IBM Lenovo oldboy
实操三:
如下,每个小字典的name对应股票名字,shares对应多少股,price对应股票的价格
portfolio = [
{‘name‘: ‘IBM‘, ‘shares‘: 100, ‘price‘: 91.1},
{‘name‘: ‘AAPL‘, ‘shares‘: 50, ‘price‘: 543.22},
{‘name‘: ‘FB‘, ‘shares‘: 200, ‘price‘: 21.09},
{‘name‘: ‘HPQ‘, ‘shares‘: 35, ‘price‘: 31.75},
{‘name‘: ‘YHOO‘, ‘shares‘: 45, ‘price‘: 16.35},
{‘name‘: ‘ACME‘, ‘shares‘: 75, ‘price‘: 115.65}
]
1、map来得出一个包含数字的迭代器,数字指的是:购买每支股票的总价格
m = map(lambda d:d["shares"]*d["price"],portfolio) l1 = list(m) print(l1) --------------输出结果--------------- [9110.0, 27161.0, 4218.0, 1111.25, 735.7500000000001, 8673.75]
2、基于1的结果,用reduce来计算,购买这些股票总共花了多少钱
l1=[9110.0, 27161.0, 4218.0, 1111.25, 735.7500000000001, 8673.75] print(reduce(lambda x,y:x+y,l1)) --------------输出结果------------------ 51009.75
3、用filter过滤出,单价大于100的股票有哪些
f = filter(lambda d:d["price"]>=100,portfolio) l2 = list(f) print(l2) -----------------------输出结果----------------------------- [{‘name‘: ‘AAPL‘, ‘shares‘: 50, ‘price‘: 543.22}, {‘name‘: ‘ACME‘, ‘shares‘: 75, ‘price‘: 115.65}]