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Owning Class: advanced
Requires: MathScript RT Module
iv = bessel_i(v, x)
iv = bessel_i(v, x, 1)
[iv, error] = bessel_i(v, x)
[iv, error] = bessel_i(v, x, 1)
Legacy Name: besseli
Computes the modified Bessel function of the first kind of a given order.
Name  Description 

v  Specifies the order of the Bessel function. v is a real, doubleprecision, floatingpoint, positive scalar, vector, or matrix. 
x  Specifies the value for which you want to compute the Bessel function. x is a real or complex, doubleprecision, floatingpoint scalar, vector, or matrix. 
1  Scales the computation. bessel_i(v, x, 1) scales bessel_i(v, x) by exp(abs(real(x))). 
Name  Description  

iv  Returns the modified Bessel function of the first kind. iv is a real or complex, doubleprecision, floatingpoint scalar, vector, or matrix.  
error  Returns error information about the evaluation of the Bessel function. error is a matrix of integers in which each element can return the following values.

bessel_i(v, x) solves the following equation: x^{2}*w''+x*w'(x^{2}+v^{2})*w = 0.
The following equation is a wellknown representation for bessel_i(v, x): bessel_i(v, x) = ((1/2)*x)^{v}*sum((z^{2}/4)^{k}/(k!*gamma(v+k+1)), k, 0, inf).
If x is a scalar, LabVIEW sets x to a vector of the same size as v whose elements all equal the value you specified for x. If y is a scalar, LabVIEW sets y to a vector of the same size as v whose elements all equal the value you specified for y. If x and v are vectors of the same orientation, LabVIEW returns a vector of Bessel functions for corresponding input values. For example, if x = [1, 2] and v = [3, 4], LabVIEW returns [bessel_i(1, 3), bessel_i(2, 4)]. If x and v are vectors of opposite orientation, LabVIEW returns a matrix of Bessel functions for each combination of input values. For example, if x = [1, 2] and v = [3; 4], LabVIEW returns [bessel_i(1, 3), bessel_i(1, 4); bessel_i(2, 3), bessel_i(2, 4)].
The following table lists the support characteristics of this function.
Supported in the LabVIEW RunTime Engine  Yes 
Supported on RT targets  Yes 
Suitable for bounded execution times on RT  Not characterized 
X = [0:0.01:2];
IV = bessel_i(2.75, X);
plot(X, IV)
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