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Member of the advanced class.

Syntax

kv = besselk(v, x)

kv = besselk(v, x, 1)

[kv, error] = besselk(v, x)

[kv, error] = besselk(v, x, 1)

Description

Computes the modified Bessel function of the second kind of a given order.

Details

Examples

Inputs

Name	Description
v	Specifies the order of the Bessel function. v is a real, double-precision, floating-point, positive scalar, vector, or matrix.
x	Specifies the value for which you want to compute the Bessel function. x is a real or complex, double-precision, floating-point scalar, vector, or matrix.
1	Scales the computation. besselk(v, x, 1) scales besselk(v, x) by exp(x).

Outputs

Name	Description
kv	Returns the modified Bessel function of the second kind. kv is a real or complex, double-precision, floating-point scalar, vector, or matrix.
error	Returns error information about the evaluation of the Bessel function. error is an integer that can return the following values. 0 Indicates that no error occurred. 1 Indicates that you specified invalid inputs. 2 Indicates that the result is too large for the data type of kv. Use the scaling option 1. 3 Indicates that LabVIEW achieved less than half the machine accuracy in the calculation because |x| or v is greater than approximately 1.3E8. 4 Indicates that the result is meaningless because |x| or v is greater than approximately 1.8E16. 5 Indicates that the calculation did not reach the termination condition so LabVIEW did not complete the calculation.

Details

besselk(v, x) solves the following equation: x²*w''+x*w'-(x²+v²)*w = 0.
The following equation is a well-known representation for besselk(v, x): besselk(v, x) = (pi/2)*(besseli(-v, x)-besseli(v, x))/sin(v*pi).

Examples

X = [0:0.01:2];
KV = besselk(2, X);
plot(X, KV)

Related Topics

airy
besschk
bessel
besselh
besseli
besselj
bessely