How to express log2 function in C language

There is no built-in log2 function in C language. It can be calculated using the following formula: log2(x) = log(x) / log(2). Usage steps: include the <math.h> header file, use log2(x) expression, and store or use for further calculations.

Expression of log2 function in C language

There is no built-in log2 function in C language. However, you can use the following equivalent expression to calculate log2:

<code class="c">#include <math.h>
double log2(double x) {
  return log(x) / log(2);
}</code>

How to use the log2 function

To use the log2 function, follow these steps:

1. Contains the <math.h> header file.
2. Use the log2(x) expression, where x is the number whose logarithm of 2 you want to calculate.
3. Store the result or use it for further calculations.

Example

The following code snippet demonstrates how to use the log2 function:

<code class="c">#include <math.h>

double x = 8;
double log2_x = log2(x);

printf("log2(%f) = %f\n", x, log2_x);</code>

Output:

<code>log2(8.000000) = 3.000000</code>

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