1 float abs(float x)    2 {   3     if(x<0) x=0-x;   4     return x;   5 }   6    7    8 float sin(float x)    9   10 {  11   12  const float B = 1.2732395447;   13  const float C = -0.4052847346;  14  const float P = 0.2310792853;//0.225;   15  float y = B * x + C * x * abs(x);  16  y = P * (y * abs(y) - y) + y;  17  return y;  18  }  19   20   21 float cos(float x)   22 {  23   const float Q = 1.5707963268;  24   const float PI =3.1415926536;  25   x += Q;   26   27   if(x > PI)   28     x -= 2 * PI;   29   30  return( sin(x));  31 }  32   33   34 float sqrt(float a)  35  {  36    double x,y;  37    x=0.0;  38    y=a/2;  39    while(x!=y)  40    {  41      x=y;  42      y=(x+a/x)/2;  43    }  44    return x;  45  }  46   47   48 float pow(float a,int b)  49 {  50     float r=a;  51     if(b>0)  52     {  53       while(--b)  54          r*=a;  55   56     }  57     else if(b<0)  58     {  59         while(++b)     r*=a;  60          r=1.0/r;  61     }  62     else r=0;  63     return r;  64 }

 

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