猛的一看  int（） round()  math.floor() 这几个函数函数好像做的是同一件事情，很容易将他们弄混，下面是他们的一些不同之处：

如下面的例子：

import math for eachnum in (.2,.7,1.2,1.7,-.2,-.7,-1.2,-1.7):  print"int(%.1f)\t%+.1f"%(eachnum,float(int(eachnum)))  print"floor(%.1f)\t%+.1f"%(eachnum,math.floor(eachnum))  print "round(%.1f)\t%+.1f"%(eachnum,round(eachnum))  print'-'*20

>>> int(0.2) +0.0 floor(0.2) +0.0 round(0.2) +0.0 -------------------- int(0.7) +0.0 floor(0.7) +0.0 round(0.7) +1.0 -------------------- int(1.2) +1.0 floor(1.2) +1.0 round(1.2) +1.0 -------------------- int(1.7) +1.0 floor(1.7) +1.0 round(1.7) +2.0 -------------------- int(-0.2) +0.0 floor(-0.2) -1.0 round(-0.2) -0.0 -------------------- int(-0.7) +0.0 floor(-0.7) -1.0 round(-0.7) -1.0 -------------------- int(-1.2) -1.0 floor(-1.2) -2.0 round(-1.2) -1.0 -------------------- int(-1.7) -1.0 floor(-1.7) -2.0 round(-1.7) -2.0 -------------------- >>>