s17ahf

Purpose

Synopsis

[fun_value,ifail] = s17ahf(x<,ifail>)

Description

 
 This routine evaluates an approximation to the Airy function 
 Bi(x). 
 
 For large negative arguments, it becomes impossible to calculate 
 the phase of the oscillating function with any accuracy so the 
                                                   2/3
                                      (     3     )       
 routine must fail. This occurs if x<-( ----------)   , where 
                                      ( 2(epsilon))          
 (epsilon) is the machine precision.
 
 For large positive arguments, there is a danger of causing 
 overflow since Bi grows in an essentially exponential manner, so 
 the routine must fail.
 

Parameters

s17ahf

Required Input Arguments:

x                                     real

Optional Input Arguments:                       <Default>

ifail                                 integer  -1

Output Arguments:

ifail                                 integer