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What is log2 in C?

Sheza Munir

Grokking Modern System Design Interview for Engineers & Managers

Ace your System Design Interview and take your career to the next level. Learn to handle the design of applications like Netflix, Quora, Facebook, Uber, and many more in a 45-min interview. Learn the RESHADED framework for architecting web-scale applications by determining requirements, constraints, and assumptions before diving into a step-by-step design process.

The log2 function allows users to calculate a number’s binary logarithm.

Library

The log2 function is accessible from the math.h library.

Syntax

double log2_of_num =  log2(double num)

Parameters

The function takes one parametera number for which a binary logarithm is needed.

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

Return value

The log2 function returns the binary logarithm of the number given as a parameter. The returned number is of datatype double.

Code

#include <stdio.h>
#include <math.h>

int main(){
   double number, log2_of_number;
   number = 32;

   log2_of_number = log2(number); //taking the common log of number
   printf("log10(%lf) = %lf\n", number, log2_of_number);
   // log2 of number will be printed
}

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c
math

CONTRIBUTOR

Sheza Munir
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Grokking Modern System Design Interview for Engineers & Managers

Ace your System Design Interview and take your career to the next level. Learn to handle the design of applications like Netflix, Quora, Facebook, Uber, and many more in a 45-min interview. Learn the RESHADED framework for architecting web-scale applications by determining requirements, constraints, and assumptions before diving into a step-by-step design process.

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