R: s18de: Modified Bessel functions I_nu + a(z), real a >= 0,...

s18de {NAGFWrappers}

R Documentation

s18de: Modified Bessel functions I_nu + a(z), real a >= 0, complex z, nu = 0 , 1 , 2 , . . .

Description

s18de returns a sequence of values for the modified Bessel functions I_ν + n(z) for complex z, non-negative ν and n = 0 , 1 , . . . , N - 1, with an option for exponential scaling.

Usage

s18de(fnu, z, n, scal)

Arguments

`fnu`	double ν , the order of the first member of the sequence of functions.
`z`	complex The argument z of the functions.
`n`	integer N , the number of members required in the sequence I_ν(z) , I_ν + 1(z) , . . . , I_ν + N - 1(z).
`scal`	string The scaling option. scal='U' : The results are returned unscaled. scal='S' : The results are returned scaled by the factor e^ - abs(Re(z)).

Details

R interface to the NAG Fortran routine S18DEF.

Value

CY

complex array

The N required function values: cy[i] contains I_ν + i - 1(z) for i=1 . . . N.

NZ

integer

The number of components of cy that are set to zero due to underflow.

IFAIL

integer

ifail =0

unless the function detects an error or a warning has been flagged (see the Errors section in Fortran library documentation).

Author(s)

NAG

References

http://www.nag.co.uk/numeric/FL/nagdoc_fl23/pdf/S/s18def.pdf

Examples


ifail<-0

fnu<-0

z<-complex(1,0.3,-0.4)

n<-2

scal<-'U'

s18de(fnu,z,n,scal)

[Package NAGFWrappers version 24.0 Index]