Python log

The Python log function is one of the Python Math functions used to calculate the logarithmic value of a given number with base E. In this section, let us discuss how to use log function in Python Programming language with example.

Syntax of a Python log Function

The syntax of the log Function in Python Programming Language is

math.log(number, base);

Base: This is an optional argument. If you omit this argument, Python log function considers default E as a logarithm base. However, you can change the value using this parameter.

Number: It can be a number or a valid numerical expression.

• If the number argument is a positive number, the log function returns the output.
• If the number argument is Negative number or Zero, log function returns ValueError
• And if the number argument is not a number, log function returns TypeError.

Python log Function Example

The Python log Function calculates the logarithmic value of the given number with base E. 

In this example, we used the log function to find the logarithmic value of different data types.

# Python LOG Function

import math

Tup = (1, 2, 3, -4 , 5) # Tuple Declaration
Lis = [-1, 2, -3.5, -4 , 5] # List Declaration

print('Logarithm value of Positive Number = %.2f' %math.log(1))
print('Logarithm value of Positive Decimal = %.2f' %math.log(2.5))

print('Logarithm value of Tuple Item = %.2f' %math.log(Tup[2]))
print('Logarithm value of List Item = %.2f' %math.log(Lis[4]))

print('Logarithm value of Multiple Number = %.2f' %math.log(2 + 7 - 5))
print('Logarithm value of String Number = ', math.log('Hello'))

OUTPUT

ANALYSIS

1. Within the first two statements, We used the log Function directly on Positive integer and Decimal values.
2. Next two statements, We used the log Function on Python Tuple and Python List items. If you observe the above screenshot, the log function is working perfectly on them.
3. Next statement, We tried log Function directly on multiple values
4. Here, We tried Python logarithmic Function on the String value, and it returns TypeError: a float is required as output
5. Next, We tried log Function on Negative value. As we said before, this is returning ValueError: math domain error as output
6. Last, We tried log Function on Zero value. As we said before, this is returning ValueError: math domain error as output