### 15.3 Airy Functions

The Airy functions \({\rm Ai}(x)\) and \({\rm Bi}(x)\) are defined in Abramowitz and Stegun, Handbook of Mathematical Functions, A&S Section 10.4 and DLMF 9.

The Airy differential equation is:

$$ {d^2 y\over dx^2} - xy = 0 $$

The numerically satisfactory pair of solutions (DLMF 9.2#T1) on the real line are \(y = {\rm Ai}(x)\) and \(y = {\rm Bi}(x).\)

These two solutions are oscillatory for x < 0. \({\rm Ai}(x)\) is the solution subject to the condition that \(y\rightarrow 0\) as \(x\rightarrow +\infty,\) and \({\rm Bi}(x)\) is the second solution with the same amplitude as \({\rm Ai}(x)\) as \(x\rightarrow-\infty\) which differs in phase by \(\pi/2.\) Also, \({\rm Bi}(x)\) is unbounded as \(x\rightarrow +\infty.\)

If the argument x is a real or complex floating point number, the numerical value of the function is returned.

Function: airy_ai (x)

  The Airy function \({\rm Ai}(x).\) See A&S eqn 10.4.2 and DLMF 9.

  See also `airy_bi`, `airy_dai`, and `airy_dbi`.

  Categories:Airy functions ·Special functions ·

Function: airy_dai (x)

  The derivative of the Airy function \({\rm Ai}(x)\):

  $$ {\rm airy\_dai}(x) = {d\over dx}{\rm Ai}(x) $$

  See `airy_ai`.

  Categories:Airy functions ·Special functions ·

Function: airy_bi (x)

  The Airy function \({\rm Bi}(x)\). See A&S eqn 10.4.3 and DLMF 9.

  See `airy_ai`, and `airy_dbi`.

  Categories:Airy functions ·Special functions ·

Function: airy_dbi (x)

  The derivative of the Airy function \({\rm Bi}(x)\):

  $$ {\rm airy\_dbi}(x) = {d\over dx}{\rm Bi}(x) $$

  See `airy_ai`, and `airy_bi`.

  Categories:Airy functions ·Special functions ·