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Reference Guide for OpenMatrix Language Functions
The Reference Guide contains documentation for all functions supported in the OpenMatrix language.
Special Functions Commands
besselk
Modified Bessel function of the second kind.

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- Scripting Guide for OpenMatrix Language
  OpenMatrix is a mathematical scripting language.
- Reference Guide for OpenMatrix Language Functions
  The Reference Guide contains documentation for all functions supported in the OpenMatrix language.
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    - besselh
      Bessel functions of the first or second kind.
    - besseli
      Modified Bessel function of the first kind.
    - besselj
      Bessel function of the first kind.
    - besselk
      Modified Bessel function of the second kind.
    - bessely
      Bessel function of the second kind.
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besselk

Modified Bessel function of the second kind.

Syntax

[k,ierr] = besselk(alpha, x, opt)

Inputs

alpha: The function order.; Type: double; Dimension: scalar | vector | matrix
x: The function argument.; Type: double | complex; Dimension: scalar | vector | matrix
opt: The scaling option.; If set to 1 or true the result contains a factor of exp(x)).; Dimension: scalar | vector | matrix

Outputs

k

The Bessel function values.

Dimension: scalar | vector | matrix

ierr

The return status flag.

Dimension: scalar | vector | matrix

info = 0: Successful return.
info = 1: Input error, returned NaN.
info = 2: Overflow condition, returned Inf.
info = 3: Calculation has lost at least half of machine accuracy.
info = 4: Calculation has lost significance, returned NaN.
info = 5: Algorithm failed to converge, returned NaN.

Examples

Unscaled example:

k = besselk(3,[10:12;13:15])

k = [Matrix] 2 x 3
2.72527e-05  9.22218e-06  3.15163e-06
1.08563e-06  3.76397e-07  1.31209e-07

Scaled example:

k = besselk(3,[10:12;13:15],1)

k = [Matrix] 2 x 3
0.60028  0.55217  0.51294
0.48030  0.45266  0.42892

Comments

If alpha and x have different dimensions, a singleton dimension in either variable is expanded to match the corresponding dimension length of the other variable.