Dear all ;

I want to use nr.f90 in order to calculate bessel functions j_L(x)
in my program.
but I see this error in runnig:

nrerror: an assertion failed with this tag:bessj_s args
program terminated by assert1

Is there anyone can help me? (this error comes from nrutil.f90 but I
don't know what should I do)

On Sep 13, 7:15 pm, Fatemeh gmail.com> wrote:

I do not have the answer to your question but if you just want to
compute a bessel function's result you might want to give the latest
Gfortran a try which has intrinsics for this (real arguments as far as
I know)

Cheers
-Ralf

Dear all ;

There is a command at the first line of bessj.f90 that when I comment
it, the program runs without any error. (this command is : call
assert(n >= 2, 'bessj_s args') )

bessj.f90:
--------------------
FUNCTION bessj_s(n,x)
USE nrtype; USE nrutil, ONLY : assert
USE nr, ONLY : bessj0,bessj1
IMPLICIT NONE
INTEGER(I4B), INTENT(IN) ...

I forgot to say that I want to calculate J_L(x) for L=0 to L=8 . but
without the mentioned comment it cannot be run even for L=0.

Hello,

On 2008-09-13 07:16:47 -0400, Fatemeh gmail.com> said:

Do you know the value of the actual arguments?

BTW, if you want very high accuracy, the NR Bessel routines
might not be the best way to compute.

I don't know why, but apparently it cannot calculate bessel function
for n<2 (for example J_L(x) for L=1 and L=0)

Is there any one that have a subroutine to calculate J_l(x) for all l?

I found the answer myself.
there are two files which is belonged to l=0 , l=1 : bessj0.f90
bessj1.f90