What is log10 in C?

The log10 function allows users to calculate the common logarithmbase 10 of a number.

Library

The log10 function is accessible from the math.h library.

Syntax

double log10(double x)

Parameters

The function takes one parameter, a number for which a common logarithm is needed.

The number needs to be positive (greater than 0) as the logarithm of negative numbers, and zero, are undefined.

Return value

The log10 returns the common logarithm of the number given as a parameter. The returned number is of double the datatype.

Code

#include <stdio.h>
#include <math.h>
int main(){
   double number, log_of_number;
   number = 100;
   log_of_number = log10(number); //taking the common log of number
   printf("log10(%lf) = %lf\n", number, log_of_number);
   // log10 of number will be printed
}

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