bessel_i_nu
Bessel-i-nu-func
Definition:
/math-67c26528abed44497376a5d192ba15f5.png "bessel\_i\_nu = bessel\_i\_nu(x,nu)")
evaluates an approximation to the modified Bessel function of the first kind I/math-4fdefba26320686bb2bd0579a0df421c.png "\nu")
/4 (x), where the order v=-3, -2, -1, 1, 2 or 3 and x is real and positive. For positive orders it may also be called with x=0, since I/4 (0)=0 when v>0. For negative orders the formula
/math-6c9d8e4162a6d7400f425f27d4688d00.png "I_{-v/4}(x)=I_{v/4}(x)+\frac{2}{\pi}\sin\left(\frac{\pi v}{4}\right)K_{v/4}(x)")
is used.
For more information please review the s18eec function in the NAG document.
Parameters:
- x (input,double)
- The argument x of the function.
- Constraints:
/math-6f7afcd293ef08f500edfcc2309008c2.png "x>0.0")
when /math-6ea6fc9eec2c784297318e751cff62bb.png "nu<0")
,/math-711da32df078b00fa470d9ddbf504ed3.png "x\geq 0.0")
when /math-5fa7f4300182b199241844612606d40c.png "nu>0")
.
- nu (input,int)
- The argument v of the function.
- Constraints:
/math-444b9207f37c2461a13f9bd94a0ba099.png "1\leq abs(nu)\leq 3")
.- bessel_i_nu (output,double)
- Approximation of the modified Bessel function of the first kind.