42 div(double a, double b)  in div()  argument
44 	return a/b;  in div()
48 mul(double a, double b)  in mul()  argument
50 	return a * b;  in mul()
54 sub(double a, double b)  in sub()  argument
56 	return a - b;  in sub()
60 div_f(float a, float b) {  in div_f()  argument
61 	return a/b;  in div_f()
65 mul_f(float a, float b) {  in mul_f()  argument
66 	return a * b;  in mul_f()
70 sub_f(float a, float b)  in sub_f()  argument
72 	return a - b;  in sub_f()