Stack Overflow
Stack Overflow

Questions tagged [bessel-functions]

The bessel functions in mathematics are the canonical solutions of Bessel's differential equation for an arbitrary complex number.

The bessel functions in mathematics are the canonical solutions of Bessel's differential equation for an arbitrary complex number. The bessel functions can be applied in programming in various cases - when calculating pressure amplitudes, waves and vibrations, free particle and floating body dynamics, and many others.

107 questions
2
votes
1 answer

How to calculate derivative and integral of the bessel functions in PYTHON

I want to calculate the integral or derivative of the modified Bessel functions in python. I want to calculate the infinite integral (without limits). Recently I found a method to do this. You can see an example for a simple function (x**2)…
Jafar
  • 73
  • 1
  • 5
2
votes
0 answers

GSL deriviative function on Bessel functions

I am trying to implement the secant method to find the roots of the bessel function. I first wrote some code that works it out by just using the straight up bessel function in gsl. I am now trying to change it to the error code so I can evaluate…
Chris U
  • 53
  • 6
2
votes
1 answer

Gnuplot fitting with modified Bessel functions

I want to fit my data in gnuplot, with a fitting relation that has the modified Bessel function of the 2nd kind in it. So let's say it kind of looks like this: f(x)= A*x + b*besselk(1,b) (I wrote it in terms of matlab or octave and the…
Poisonedhoney
  • 41
  • 3
2
votes
2 answers

Newton Raphson code in R involving integration and Bessel function

I have want to estimate the parameters of the function which involves Bessel function and integration. However, when i tried to run it, i got a message that "Error in f(x, ...) : could not find function "BesselI" ". I don't know to fix it and would…
Ahmed
  • 21
  • 4
2
votes
1 answer

What is the exact equivalent of "Matlab besselk(x,y,1)" in c++?

I have tried boost::math::cyl_bessel_k(x,y) * exp(y). In most cases, this is equal to Matlab's scaled besselk(x,y,1). But in some cases (e.g., x=1, y=2000) when both besselk(x,y)=0 and boost::math::cyl_bessel_k(x,y)=0, Matlab's scaled version…
taha
  • 172
  • 8
2
votes
1 answer

Density plot with python making a Diffraction pattern with Bessel Integrals but it wont stop running

I am trying to make a circular diffraction pattern, which has a central spot surrounded by a series of rings. It involves a Bessel integral to do it which is defined in the code. My problems is that it takes too long like I waited 10 min for the…
FireFistAce
  • 41
  • 3
  • 12
2
votes
0 answers

Why won't boost's bessel function compile with a complex input?

According to the boost documentation, the boost special functions bessel function (specifically the modified bessel function) should be able to accept a complex input. However, when I attempt to feed it one, I get a compile error complaining that…
stix
  • 1,140
  • 13
  • 36
2
votes
1 answer

Zeroth-order Bessel function Python

Apologies for the simplicity of this question. I would like to implement an equation in Python. In this equation, K_0 is the zeroth-order modifed Bessel function. What is the best way of implementing K_0 in Python?
8765674
  • 1,234
  • 4
  • 17
  • 32
2
votes
1 answer

Representing a simple function with 0th Bessel Function

I am sorry if I sound stupid or vague, but I have a question regarding a code about Bessel functions. I was tasked with the homework of representing a simple function, (f(x)=1-x to be exact) using the first five 0th order Bessel functions whos zeros…
Additional Pylons
  • 138
  • 5
2
votes
5 answers

Bessel library function in Java

I'm looking for a bessel function in Java that matches the Excel function BESSELI, description provided: Returns the modified Bessel function, which is equivalent to the Bessel function evaluated for purely imaginary…
David Turner
  • 5,014
  • 6
  • 26
  • 27
1
vote
1 answer

Plotting and finding roots of bessel functions

I am trying to plot roots of a function that is composed of multiple bessel functions being added and multiplied in Matlab. The equation is Jm(omega)*Ik(omega)+Im(omega)*Jk(omega) where Jm is the bessel function of the first kind of order m…
A Anderson
  • 35
  • 2
  • 4
1
vote
1 answer

zeros of the derivative of the spherical Bessel function

I make reference to the function in Scipy here. I want to calculate the zeros of the derivative of the function j'_n(x). Any propositions for how to do it ?
alpha027
  • 302
  • 2
  • 13
1
vote
1 answer

How to combine scipy interp1d with mpmath quadosc

I have a density function (from quantum mechanics calculations) to be multiplied with the spherical Bessel function with a momentum grid (momentum q 1d array, real space distance r 1d array, so need to calculate jn(q*r) 2d array). The product will…
Zezhong Zhang
  • 13
  • 3
1
vote
1 answer

Julia and Bessel functions

I am interested in Julia and would like to understand a couple of things before I dive into it. I would like to have a look at a working code which calculates this expression. In that expression everything is a constant but for the Bessel functions,…
Mare Dedeu
  • 19
  • 2
1
vote
1 answer

How do I implement BesselJ functions in tensorflow

tensorflow inner functions supports the Bessel function BesselI tensorflow besseli0. However, it does not have BesselJ functions (especially BesselJ[2,x]). If I were to approximate this function, I would have to use If in tensorflow, which is not…
ZHANG Juenjie
  • 501
  • 5
  • 20
1
2
3 4 5 6 7 8