Question

I am a beginner in python and cant understand why this is happening:

from math import *
print "enter the number"
n=int(raw_input())
d=2
s=0
while d<n :
    if n%d==0:
       x=math.log(d)
       s=s+x
       print d
    d=d+1
print s,n,float(n)/s   

Running it in Python and inputing a non prime gives the error

Traceback (most recent call last):
  File "C:\Python27\mit ocw\pset1a.py", line 28, in <module>
    x=math.log(d)
NameError: name 'math' is not defined

Answer 1

Change

from math import *

to

import math

Using from X import * is generally not a good idea as it uncontrollably pollutes the global namespace and could present other difficulties.