Beta function¶
Beta functions for real and complex values
Defined via the analytic continuation of the Gamma function.
- boring_math.special_functions.gamma_family.beta.beta(u: complex, v: complex) complex¶
Beta function for all complex u and v.
- param u:
First argument to analytically continued beta function.
- param v:
Second argument to analytically continued beta function.
- returns:
Value of beta(u,v) where inf+infj is returned to represent a single complex infinity.
Note
For all u, v ∈ ℂ and m, n ∈ ℕ, we have
B(u, v) = B(v, u)
B(0, v) = Γ(0) = ∞
B(m, -n) = ∞ when m > n > 0
B(m, -n) = Γ(m) * (Res[Γ, -n]/Res[Γ, m-n]) when m <= n
where ∀(n>=0) Res[Γ(z), z = -n] = (-1)ⁿ/(n!)
Note
Using natural logs in calculation for more numerical stability.
- boring_math.special_functions.gamma_family.beta.beta_real(x: float, y: float) float¶
Beta function valid for all real values x, y > 1.
- param x:
First argument to analytically continued beta function.
- param y:
Second argument to analytically continued beta function.
- returns:
Value of beta(x, y) where inf is returned to denote singular points.
- raises ValueError:
If x <= 0 or y <= 0.
Note
Using natural logs for more numerical stability.
Warning
Not valid for extended value reals.