# Fortran Wiki bessel_j1

## Description

bessel_j1(x) computes the Bessel function of the first kind of order 1 of x.

## Standard

Fortran 2008 and later

## Class

Elemental function

## Syntax

result = bessel_j1(x)

## Arguments

• x - The type shall be real.

## Return value

The return value is of type real and lies in the range $- 0.5818... \leq Bessel (0,x) \leq 0.5818$. It has the same kind as x.

## Example

program test_besj1
real(8) :: x = 1.0_8
x = bessel_j1(x)
end program test_besj1