41 div(double a, double b)  in div()  argument
43 	return a/b;  in div()
47 mul(double a, double b)  in mul()  argument
49 	return a * b;  in mul()
53 sub(double a, double b)  in sub()  argument
55 	return a - b;  in sub()
59 div_f(float a, float b) {  in div_f()  argument
60 	return a/b;  in div_f()
64 mul_f(float a, float b) {  in mul_f()  argument
65 	return a * b;  in mul_f()
69 sub_f(float a, float b)  in sub_f()  argument
71 	return a - b;  in sub_f()