C math.h Library

C `math.h` Library

In C math.h Library provides a set of mathematical functions for calculations like exponentiation, logarithms, trigonometry, rounding, and more. It’s widely used in scientific, engineering, and graphics applications.

Note: Always compile with -lm flag in GCC to link the math library.
Example: gcc program.c -o program -lm

📌 Common Math Functions

1️⃣ Basic Arithmetic Functions

Function	Description
`abs(int x)`	Returns absolute value of an integer
`fabs(double x)`	Returns absolute value of a floating-point number
`fmod(double x, double y)`	Returns remainder of `x/y`

Example:

2️⃣ Power and Root Functions

Function	Description
`pow(double x, double y)`	Returns `x` raised to the power `y`
`sqrt(double x)`	Returns square root of `x`
`cbrt(double x)`	Returns cube root of `x`

Example:

3️⃣ Exponential and Logarithmic Functions

Function	Description
`exp(double x)`	Returns `e^x`
`log(double x)`	Natural logarithm (ln)
`log10(double x)`	Base-10 logarithm

Example:

4️⃣ Trigonometric Functions

Function	Description
`sin(double x)`	Sine of x (radians)
`cos(double x)`	Cosine of x
`tan(double x)`	Tangent of x
`asin(double x)`	Arcsine (inverse sine)
`acos(double x)`	Arccosine
`atan(double x)`	Arctangent
`atan2(double y, double x)`	Arctangent of y/x with correct quadrant

Example:

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

int main() {
double angle = M_PI/4; // 45 degrees in radians

printf("sin(45°) = %.2f\n", sin(angle));
printf("cos(45°) = %.2f\n", cos(angle));
printf("tan(45°) = %.2f\n", tan(angle));

return 0;
}

#include <stdio.h>

#include <math.h>

int main() {

double angle = M_PI/4; // 45 degrees in radians

printf("sin(45°) = %.2f\n", sin(angle));

printf("cos(45°) = %.2f\n", cos(angle));

printf("tan(45°) = %.2f\n", tan(angle));

return 0;

}

Note: M_PI is defined in math.h for the value of π.

5️⃣ Rounding and Ceiling/Floor Functions

Function	Description
`ceil(double x)`	Returns smallest integer >= x
`floor(double x)`	Returns largest integer <= x
`round(double x)`	Rounds to nearest integer
`trunc(double x)`	Truncates fractional part
`fabs(double x)`	Absolute value (floating-point)

Example:

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

int main() {
double x = 5.7, y = -3.2;

printf("ceil(5.7) = %.2f\n", ceil(x));
printf("floor(5.7) = %.2f\n", floor(x));
printf("round(5.7) = %.2f\n", round(x));
printf("trunc(-3.2) = %.2f\n", trunc(y));

return 0;
}

#include <stdio.h>

#include <math.h>

int main() {

double x = 5.7, y = -3.2;

printf("ceil(5.7) = %.2f\n", ceil(x));

printf("floor(5.7) = %.2f\n", floor(x));

printf("round(5.7) = %.2f\n", round(x));

printf("trunc(-3.2) = %.2f\n", trunc(y));

return 0;

}

6️⃣ Other Useful Functions

Function	Description
`hypot(double x, double y)`	Returns `√(x² + y²)`
`pow10(double x)`	Returns `10^x` (sometimes `powl` for long double)
`fmax(double x, double y)`	Returns maximum of two numbers
`fmin(double x, double y)`	Returns minimum of two numbers

Example:

📌 Summary Table

Category	Functions
Absolute Value	`abs`, `fabs`
Power & Roots	`pow`, `sqrt`, `cbrt`
Log & Exp	`log`, `log10`, `exp`
Trigonometry	`sin`, `cos`, `tan`, `asin`, `acos`, `atan`, `atan2`
Rounding	`ceil`, `floor`, `round`, `trunc`
Misc	`fmod`, `hypot`, `fmax`, `fmin`

✅ Notes

Trigonometric functions use radians, not degrees.
Always compile with -lm to link math library.
For high-precision, use long double versions: powl, sqrtl, etc.
Use fmod instead of % for floating-point remainder.

C math.h Library

C math.h Library

📌 Common Math Functions

1️⃣ Basic Arithmetic Functions

2️⃣ Power and Root Functions

3️⃣ Exponential and Logarithmic Functions

4️⃣ Trigonometric Functions

5️⃣ Rounding and Ceiling/Floor Functions

6️⃣ Other Useful Functions

📌 Summary Table

✅ Notes

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