Arduino - 数学图书馆( Math Library)
Arduino Math库（math.h）包含许多用于处理浮点数的有用数学函数。
Library宏 (Library Macros)
以下是头部math.h中定义的宏 -
Library 函数
标题math.h中定义了以下函数 -
例子 (Example)
以下示例显示如何使用最常见的math.h库函数 -
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() {
}
结果 (Result)
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
