CODEWITHSUNDEEP
pythonmathlogarithm
user5745186
user5745186

Reputation:

why python gives the such an error " float division by zero" while evaluating "log(e,1)"

I've defined a function which is 

from math import *

def func(x):

    return log(e,x)

Error is short and clear, do you know why python cannot evaluate 

func(1)

,which is equal to ln(1), ?

edit: Since I'm new there, I have posted a silly question, I'm sorry, but now I handled it

Upvotes: 1

Views: 2393

Answers (2)

python
python

Reputation: 4521

This is the definition of the log function. As mentioned in the comments, your base cannot be 1.

def log(x, base=None): # real signature unknown; restored from __doc__
        """
        log(x[, base])

        Return the logarithm of x to the given base.
        If the base not specified, returns the natural logarithm (base e) of x.
        """
        pass

You can see the below operations:- 

>>> import math
>>> 
>>> def func(x):
... 
...     return math.log(10, x)
... 
>>> print func(1)
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "<input>", line 3, in func
ZeroDivisionError: float division by zero
>>> print func(2)
3.32192809489
>>> print func(3)
2.09590327429
>>> print func(4)
1.66096404744
>>>

Upvotes: 2

user5745186
user5745186

Reputation:

@mike_z was right about what he recommended,

I had a piece of backward arguments, in other words I thinked of the function

math.log(a,b) or log(a,b)

(depending on how you impoted math modulo)

as if a indicates base ,and b indicates the other operand whose logarithm is to be evaluated

but the true approach is that inverse of sentence above is right,

Tank you all!

Upvotes: 2

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