---
name: "PDL::GSLSF::BESSEL"
section: "3pm"
platform: "linux"
package: "pdl"
version: "1:2.081-2"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/PDL::GSLSF::BESSEL"
---

# PDL::GSLSF::BESSEL(3pm)

PDL interface to GSL Special Functions

## NAME

PDL::GSLSF::BESSEL - PDL interface to GSL Special Functions

## DESCRIPTION

This is an interface to the Special Function package present in the GNU Scientific Library.

## FUNCTIONS

### gsl\_sf\_bessel\_Jn

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Regular Bessel Function J\_n(x).

gsl\_sf\_bessel\_Jn does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Jn\_array

```
  Signature: (double x(); double [o]y(num); int s; int n=>num)
```

Array of Regular Bessel Functions J\_{s}(x) to J\_{s+n-1}(x).

gsl\_sf\_bessel\_Jn\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Yn

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

IrRegular Bessel Function Y\_n(x).

gsl\_sf\_bessel\_Yn does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Yn\_array

```
  Signature: (double x(); double [o]y(num); int s; int n=>num)
```

Array of Regular Bessel Functions Y\_{s}(x) to Y\_{s+n-1}(x).

gsl\_sf\_bessel\_Yn\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_In

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Regular Modified Bessel Function I\_n(x).

gsl\_sf\_bessel\_In does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_I\_array

```
  Signature: (double x(); double [o]y(num); int s; int n=>num)
```

Array of Regular Modified Bessel Functions I\_{s}(x) to I\_{s+n-1}(x).

gsl\_sf\_bessel\_I\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_In\_scaled

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Scaled Regular Modified Bessel Function exp(-\|x\|) I\_n(x).

gsl\_sf\_bessel\_In\_scaled does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_In\_scaled\_array

```
  Signature: (double x(); double [o]y(num); int s; int n=>num)
```

Array of Scaled Regular Modified Bessel Functions exp(-\|x\|) I\_{s}(x) to exp(-\|x\|) I\_{s+n-1}(x).

gsl\_sf\_bessel\_In\_scaled\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Kn

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

IrRegular Modified Bessel Function K\_n(x).

gsl\_sf\_bessel\_Kn does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_K\_array

```
  Signature: (double x(); double [o]y(num); int s; int n=>num)
```

Array of IrRegular Modified Bessel Functions K\_{s}(x) to K\_{s+n-1}(x).

gsl\_sf\_bessel\_K\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Kn\_scaled

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Scaled IrRegular Modified Bessel Function exp(-\|x\|) K\_n(x).

gsl\_sf\_bessel\_Kn\_scaled does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Kn\_scaled\_array

```
  Signature: (double x(); double [o]y(num); int s; int n=>num)
```

Array of Scaled IrRegular Modified Bessel Functions exp(-\|x\|) K\_{s}(x) to exp(-\|x\|) K\_{s+n-1}(x).

gsl\_sf\_bessel\_Kn\_scaled\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_jl

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Regular Sphericl Bessel Function J\_n(x).

gsl\_sf\_bessel\_jl does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_jl\_array

```
  Signature: (double x(); double [o]y(num); int n=>num)
```

Array of Spherical Regular Bessel Functions J\_{0}(x) to J\_{n-1}(x).

gsl\_sf\_bessel\_jl\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_yl

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

IrRegular Spherical Bessel Function y\_n(x).

gsl\_sf\_bessel\_yl does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_yl\_array

```
  Signature: (double x(); double [o]y(num); int n=>num)
```

Array of Regular Spherical Bessel Functions y\_{0}(x) to y\_{n-1}(x).

gsl\_sf\_bessel\_yl\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_il\_scaled

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Scaled Regular Modified Spherical Bessel Function exp(-\|x\|) i\_n(x).

gsl\_sf\_bessel\_il\_scaled does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_il\_scaled\_array

```
  Signature: (double x(); double [o]y(num); int n=>num)
```

Array of Scaled Regular Modified Spherical Bessel Functions exp(-\|x\|) i\_{0}(x) to exp(-\|x\|) i\_{n-1}(x).

gsl\_sf\_bessel\_il\_scaled\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_kl\_scaled

```
  Signature: (double x(); double [o]y(); double [o]e(); int n)
```

Scaled IrRegular Modified Spherical Bessel Function exp(-\|x\|) k\_n(x).

gsl\_sf\_bessel\_kl\_scaled does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_kl\_scaled\_array

```
  Signature: (double x(); double [o]y(num); int n=>num)
```

Array of Scaled IrRegular Modified Spherical Bessel Functions exp(-\|x\|) k\_{s}(x) to exp(-\|x\|) k\_{s+n-1}(x).

gsl\_sf\_bessel\_kl\_scaled\_array does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Jnu

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

Regular Cylindrical Bessel Function J\_nu(x).

gsl\_sf\_bessel\_Jnu does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Ynu

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

IrRegular Cylindrical Bessel Function J\_nu(x).

gsl\_sf\_bessel\_Ynu does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Inu\_scaled

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

Scaled Modified Cylindrical Bessel Function exp(-\|x\|) I\_nu(x).

gsl\_sf\_bessel\_Inu\_scaled does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Inu

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

Modified Cylindrical Bessel Function I\_nu(x).

gsl\_sf\_bessel\_Inu does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Knu\_scaled

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

Scaled Modified Cylindrical Bessel Function exp(-\|x\|) K\_nu(x).

gsl\_sf\_bessel\_Knu\_scaled does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_Knu

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

Modified Cylindrical Bessel Function K\_nu(x).

gsl\_sf\_bessel\_Knu does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

### gsl\_sf\_bessel\_lnKnu

```
  Signature: (double x(); double [o]y(); double [o]e(); double n)
```

Logarithm of Modified Cylindrical Bessel Function K\_nu(x).

gsl\_sf\_bessel\_lnKnu does not process bad values. It will set the bad-value flag of all output ndarrays if the flag is set for any of the input ndarrays.

## AUTHOR

This file copyright (C) 1999 Christian Pellegrin \<chri@infis.univ.trieste.it\> All rights reserved. There is no warranty. You are allowed to redistribute this software / documentation under certain conditions. For details, see the file COPYING in the PDL distribution. If this file is separated from the PDL distribution, the copyright notice should be included in the file.

The GSL SF modules were written by G. Jungman.