What is Power Function in C Library?

What is the Power Function in C?

The power function in C is used to raise a number (called the base) to the power of another number (called the exponent). In simple terms, it computes:

pow(base, exponent) = base ^ exponent

For example:

pow(2, 3) = 2 × 2 × 2 = 8

Syntax of pow() Function

To use the pow() function, include the math.h header file in your program:​

#include <math.h>

The function prototype is:​

double pow(double base, double exponent);

• base – the number to be raised.
• exponent – the power to which the base is raised.

Example of Power Function in C

#include <stdio.h>
#include <math.h>
 
int main() {
    double quizMarks = 3.0;
    double attempts = 4.0;
 
    double totalScore = pow(quizMarks, attempts); // 3^4 = 81
 
    printf("C Programming Score: %.2f\n", totalScore);
    return 0;
}

Output:

C Programming Score: 81.00

This C program calculates a score using the pow() function from the library. It sets quizMarks to 3.0 and attempts to 4.0. Using pow(quizMarks, attempts), it calculates 3 raised to the power of 4, which gives 81. The result is stored in totalScore and printed with two decimal places. This simple example shows how to use power functions for mathematical tasks in C.

Important Notes:

• Always include math.h or you’ll get an “implicit declaration” warning.
• Compile with -lm if using GCC:

gcc program.c -o program -lm

• Return value is of type double, so you may need to cast it if you want an integer.

int result = (int)pow(2, 3);  // result = 8

• If you pass a negative base with a non-integer exponent, the result is undefined (NaN).

pow() Function with Different Data Types

Although pow() accepts and returns double, you can use it with integers by typecasting:

int base = 5, exp = 2;
int result = (int)pow((double)base, (double)exp);  // result = 25

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