Skip to main content
`Ctrl`+`K`

# scipy.special.airye

scipy.special.airye(z, out=None) = <ufunc 'airye'>

  Exponentially scaled Airy functions and their derivatives.

  Scaling:

      eAi  = Ai  * exp(2.0/3.0*z*sqrt(z))
      eAip = Aip * exp(2.0/3.0*z*sqrt(z))
      eBi  = Bi  * exp(-abs(2.0/3.0*(z*sqrt(z)).real))
      eBip = Bip * exp(-abs(2.0/3.0*(z*sqrt(z)).real))

  Parameters:
    z array_like

      Real or complex argument.

    out tuple of ndarray, optional

      Optional output arrays for the function values

  Returns:
    eAi, eAip, eBi, eBip 4-tuple of scalar or ndarray

      Exponentially scaled Airy functions eAi and eBi, and their derivatives eAip and eBip

  See also

  `airy`

  Notes

  Wrapper for the AMOS [1] routines zairy and zbiry.

  References

  [1]

  Donald E. Amos, “AMOS, A Portable Package for Bessel Functions of a Complex Argument and Nonnegative Order”, http://netlib.org/amos/

  Examples

  We can compute exponentially scaled Airy functions and their derivatives:

      >>> import numpy as np
      >>> from scipy.special import airye
      >>> import matplotlib.pyplot as plt
      >>> z = np.linspace(0, 50, 500)
      >>> eAi, eAip, eBi, eBip = airye(z)
      >>> f, ax = plt.subplots(2, 1, sharex=True)
      >>> for ind, data in enumerate([[eAi, eAip, ["eAi", "eAip"]],
      ...                             [eBi, eBip, ["eBi", "eBip"]]]):
      ...     ax[ind].plot(z, data[0], "-r", z, data[1], "-b")
      ...     ax[ind].legend(data[2])
      ...     ax[ind].grid(True)
      >>> plt.show()

  We can compute these using usual non-scaled Airy functions by:

      >>> from scipy.special import airy
      >>> Ai, Aip, Bi, Bip = airy(z)
      >>> np.allclose(eAi, Ai * np.exp(2.0 / 3.0 * z * np.sqrt(z)))
      True
      >>> np.allclose(eAip, Aip * np.exp(2.0 / 3.0 * z * np.sqrt(z)))
      True
      >>> np.allclose(eBi, Bi * np.exp(-abs(np.real(2.0 / 3.0 * z * np.sqrt(z)))))
      True
      >>> np.allclose(eBip, Bip * np.exp(-abs(np.real(2.0 / 3.0 * z * np.sqrt(z)))))
      True

  Comparing non-scaled and exponentially scaled ones, the usual non-scaled function quickly underflows for large values, whereas the exponentially scaled function does not.

      >>> airy(200)
      (0.0, 0.0, nan, nan)
      >>> airye(200)
      (0.07501041684381093, -1.0609012305109042, 0.15003188417418148, 2.1215836725571093)