如何在python中进行浮点计算？

Question

How to do floating point computation in python ?

  for j in range(10 , 50):      
         print "(10/(j+1)) is %f " % (10/(j+1))

Why is the output all 0s ?

j must be an integer , but I need the floating result .

thanks

Answer 1

In Python2, / will truncate the quotient of two integers into an integer,

you can either do

  for j in range(10 , 50):      
      print "(10/(j+1)) is %f " % (10.0/(j+1))

or not to truncate globally, just as Python3 does

from __future__ import division

for j in range(10 , 50):      
    print "(10/(j+1)) is %f " % (10/(j+1))

Answer 2

try 10.0 instead of 10. python is interpreting the 10 as an integer type and the division as a result is integer division. You could also cast 10 or (j + 1) to a double type manually but 10.0 seems the easiest to me.