math.log(243,3) problem

In python:

1
2
3
4

import math
math.log(243,3)
4.999999999999999

1. 1 2 3

   import math math.log10(243)/math.log10(3) 5

2. 1 2 3 4 5 6 7 8 9

   import math >>> x = math.log(243,3) # Judge whether an int >>> judge = (round(x)-x) < 0.0000001 True # get the Int value >>> round(x)