scipy.special.stdtr

scipy.special.stdtr(x1, x2[, out])

p=stdtr(df,t) returns the integral from minus infinity to t of the Student t distribution with df > 0 degrees of freedom: gamma((df+1)/2)/(sqrt(df*pi)*gamma(df/2)) * integral((1+x**2/df)**(-df/2-1/2), x=-inf..t)