Method on @sym: gammainc (x, a) ¶

Method on @sym: gammainc (x, a, ’lower’) ¶

Method on @sym: gammainc (x, a, ’upper’) ¶

Symbolic regularized incomplete gamma function.

Example:

syms x a
gammainc(x, a)
  ⇒ (sym)
      γ(a, x)
      ───────
        Γ(a)

gammainc(x, a, 'upper')
  ⇒ (sym)
      Γ(a, x)
      ───────
        Γ(a)

Note the order of inputs is swapped in the displayed symbolic expression, ‘@sym/igamma’. This is purely cosmetic and does not effect operations on the results:

gammainc(3, 1)
  ⇒ ans = 0.9502
gammainc(x, a)
  ⇒ (sym)
      γ(a, x)
      ───────
        Γ(a)
double(subs(ans, [x a], [3 1]))
  ⇒ ans = 0.9502

See also: gammainc, @sym/igamma, @sym/gamma.

Package: symbolic