I = besseli(alpha,x)E = besseli(alpha,x,1)
I = besseli(alpha,x) computes modified Bessel functions of the first kind for real, non-negative order alpha and argument x. If alpha is a scalar and x is a vector, I is a vector the same length as x. If x is a vector of length m and alpha is a vector of length n, then I is an m-by-n matrix and I(i,k) is besseli(alpha(k), x(i)). The elements of x can be any nonnegative real values, in any order. For alpha, the increment between elements must be 1, and all elements must be between 0 and 1000, inclusive.
E = besseli(alpha,x,1) computes besseli(alpha,x).*exp(-x).
The relationship between the modified Bessel function of the first kind I and the Bessel function of the first kind J is
besseli uses three-term backward recurrence for most x, and an asymptotic expansion for large x.
bessel,besselj,besselk,bessely
(c) Copyright 1994 by The MathWorks, Inc.