return exp (-z / (2. * (1 - r * r))) * (2. * M_PI * sqrt (1 - r * r));
}
double
idf_fdist (double P, double df1, double df2)
{
return exp (-z / (2. * (1 - r * r))) * (2. * M_PI * sqrt (1 - r * r));
}
double
idf_fdist (double P, double df1, double df2)
{