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double round(double v)

{

double dOverDot  = double(int(v));

double dUnderDot = v - dOverDot;

if(dUnderDot > 0)

{

if( dUnderDot >= 0.5 ) dOverDot += 1.0;

}

else if(dUnderDot < 0)

{

if( dUnderDot <= -0.5 ) dOverDot -= 1.0;

}

return dOverDot;

}

double round_to_digits(double value, int digits)

{

double factor = pow(10.0, digits - ceil(log10(fabs(value))));

return round(value * factor) / factor;   

}