C frexp() Function

Posted in C Tutorial

Updated on Jan 13, 2024

By Mari Selvan

👁️ 179 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In C programming, the <math.h> library provides a set of functions for mathematical operations.

The frexp() function is one such function that breaks down a floating-point value into its normalized fraction and exponent components. This can be useful in certain numerical operations.

In this tutorial, we'll explore the usage and functionality of the frexp() function in C.

💡 Syntax

The syntax for the frexp() function is as follows:

Syntax

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double frexp(double x, int *exp);

x: The floating-point number to be broken into a normalized fraction and exponent.
exp: A pointer to an integer where the exponent is stored.

📄 Example

Let's dive into an example to illustrate how the frexp() function works.

frexp.c

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

int main() {
  double x = 123.45;
  int exponent;

  // Get the normalized fraction and exponent
  double fraction = frexp(x, & exponent);

  // Output the result
  printf("Original value: %f\n", x);
  printf("Normalized fraction: %f\n", fraction);
  printf("Exponent: %d\n", exponent);

  return 0;
}

💻 Output

Output

Original value: 123.450000
Normalized fraction: 0.964453
Exponent: 7

🧠 How the Program Works

In this example, the frexp() function is used to break down the floating-point number 123.45 into its normalized fraction and exponent components.

↩️ Return Value

The frexp() function returns the normalized fraction of the input value (x). The exponent is stored in the variable pointed to by the exp parameter.

📚 Common Use Cases

The frexp() function is particularly useful when you need to analyze or manipulate the components of a floating-point number separately. It allows you to extract the normalized fraction and exponent, which can be beneficial in certain mathematical computations.

📝 Notes

The normalized fraction returned by frexp() is in the range [0.5, 1) for nonzero values of x.
The exponent is an integer such that x is equal to fraction * 2^exp.

🎢 Optimization

The frexp() function is typically optimized for efficiency. No specific optimizations are needed.

🎉 Conclusion

The frexp() function in C is a valuable tool for breaking down floating-point numbers into their normalized fraction and exponent components. It provides a way to analyze and manipulate the internal representation of floating-point values.

Feel free to experiment with different floating-point numbers and explore how the frexp() function behaves in various scenarios. Happy coding!