The Arduino Math library (math.h) includes a number of useful mathematical functions for manipulating floating-point numbers.
Following are the macros defined in the header math.h −
The following functions are defined in the header math.h −
The following example shows how to use the most common math.h library functions −
double double__x = 45.45 ;double double__y = 30.20 ;void setup() {
Serial.begin(9600);
Serial.print("cos num = ");
Serial.println (cos (double__x) ); // returns cosine of x
Serial.print("absolute value of num = ");
Serial.println (fabs (double__x) ); // absolute value of a float
Serial.print("floating point modulo = ");
Serial.println (fmod (double__x, double__y)); // floating point modulo
Serial.print("sine of num = ");
Serial.println (sin (double__x) ) ;// returns sine of x
Serial.print("square root of num : ");
Serial.println ( sqrt (double__x) );// returns square root of x
Serial.print("tangent of num : ");
Serial.println ( tan (double__x) ); // returns tangent of x
Serial.print("exponential value of num : ");
Serial.println ( exp (double__x) ); // function returns the exponential value of x.
Serial.print("cos num : ");
Serial.println (atan (double__x) ); // arc tangent of x
Serial.print("tangent of num : ");
Serial.println (atan2 (double__y, double__x) );// arc tangent of y/x
Serial.print("arc tangent of num : ");
Serial.println (log (double__x) ) ; // natural logarithm of x
Serial.print("cos num : ");
Serial.println ( log10 (double__x)); // logarithm of x to base 10.
Serial.print("logarithm of num to base 10 : ");
Serial.println (pow (double__x, double__y) );// x to power of y
Serial.print("power of num : ");
Serial.println (square (double__x)); // square of x}void loop() {}cos num = 0.10 absolute value of num = 45.45 floating point modulo =15.25 sine of num = 0.99 square root of num : 6.74 tangent of num : 9.67 exponential value of num : ovf cos num : 1.55 tangent of num : 0.59 arc tangent of num : 3.82 cos num : 1.66 logarithm of num to base 10 : inf power of num : 2065.70