Last time we checked the type and said if it is a float you're okay. If not, carry on.

并且会告之是否是一个浮点数,如果不是继续循环。

麻省理工公开课 - 计算机科学及编程导论课程节选

I can't rely on the user. I want to make sure I get a float in it, so how do I do that?

我想确保这儿我得到的是一个浮点数,我该怎么做呢？

麻省理工公开课 - 计算机科学及编程导论课程节选