跟老齐学Python 这个例子怎么运行不对？

[pendave]

reduce(lambda sum,(x,y): sum+x*y,zip(a,b),0)
我直接复制出来

[qiwsir]

请购买《跟老齐学Python：轻松入门》,在书中我对reduce有阐述。网上的内容不保证校对。 <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> 无病毒。www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> 2017-12-22 13:55 GMT+08:00 pendave <[email protected]>:

…

[image: 35ed d60 l160vp9 3t 47e] <https://user-images.githubusercontent.com/1331881/34287060-b1757050-e71f-11e7-8f15-8a197c68b27b.jpg> [image: g9 of5_ 61vmf a q5 hrkh] <https://user-images.githubusercontent.com/1331881/34287065-b783f976-e71f-11e7-88b2-c3a21a5df6cd.png> [image: jh655ie j14 njoz 3lvlwy] <https://user-images.githubusercontent.com/1331881/34287072-bfb38a9e-e71f-11e7-8195-e290bd22eae5.jpg> reduce(lambda sum,(x,y): sum+x*y,zip(a,b),0) 我直接复制出来 — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#127>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ADel62L4Jiij_lxl8g0i4Ur5pIXN788Yks5tC0RegaJpZM4RKrCt> .

-- *QiWei*

[jintianming]

你的邮件收到，谢谢！

[fish1968]

https://stackoverflow.com/questions/11328312/python-lambda-does-not-accept-tuple-argument 参考这里，使用 tuple 作为 lambda 参数的特性在 python3 中被取消了，可以改为

reduce(add,map(lambda x: x[0]*x[1], zip(a,b)))
reduce(lambda x,y: x+y, map(lambda x,y: x*y, a, b))
reduce(lambda x,y: x+y[0]*y[1], zip(a,b),0) # 0 must be provided here, otherwise the first tuple of zip(a,b) would be the initial value, and error happens due to tuple type added with int type