R = betainc(X, Z, W)
R = betainc(X, Z, W, tail)
| Parameter | Description |
|---|---|
| X | a real single or real double matrix. It must be in the closed interval [0, 1]. |
| Z | a real single or real double matrix. It must be nonnegative. |
| W | a real single or real double matrix. It must be nonnegative. |
| tail | a string 'upper' or 'lower' (default). |
| Parameter | Description |
|---|---|
| R | result of betainc function. |
betainc computes the incomplete beta function (regularized).
The incomplete beta function is defined as:
$$I_x(a,b) = \frac{B(x; a,b)}{B(a,b)} = \frac{1}{B(a,b)} \int_0^x t^{a-1} (1-t)^{b-1} \, dt$$where
$$B(a,b) = \int_0^1 t^{a-1} (1-t)^{b-1} \, dt$$is the complete beta function, and:
$$B(a,b) = \frac{\Gamma(a)\Gamma(b)}{\Gamma(a+b)}$$The function is normalized so that
$$I_1(a,b) = 1$$.All arrays must be the same size or any of them can be scalar.
R = betainc(0.5, 1:10, 3)| Version | Description |
|---|---|
| 1.0.0 | initial version |