BESSEL_J1 — Bessel function of the first kind of order 1#

BESSEL_J1(X)#

BESSEL_J1(X) computes the Bessel function of the first kind of order 1 of X. This function is available under the name BESJ1 as a GNU extension.

Parameters:

X – The type shall be REAL.

Returns:

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.

Standard:

Fortran 2008

Class:

Elemental function

Syntax:
RESULT = BESSEL_J1(X)
Example:
program test_besj1
  real(8) :: x = 1.0_8
  x = bessel_j1(x)
end program test_besj1
Specific names:

Name

Argument

Return type

Standard

DBESJ1(X)

REAL(8) X

REAL(8)

GNU extension