MATLAB: How to implement Bessel’s function in MATLAB

bessel functionMATLABsimulinktld

i want to find the solution of this bessels function mentioned

please help me to model the same in matlab or simulink

Best Answer

https://www.mathworks.com/help/matlab/ref/besselj.html for the numeric version

https://www.mathworks.com/help/symbolic/besselj.html for the symbolic version

When Bessel functions are being used, it is not uncommon to find that you need higher precision than double precision can provide, so it is common to need to use the symbolic version. To be more precise, often calculation of the values needs a higher range than double precision can support: it is common to end up with formulas that involve the ratio of two large numbers, and even though the ratio might be in the 1/1000 to 2 range, the individual numbers overflow to infinity in double precision.

Related Solutions

MATLAB: How to evaluate the derivatives of a Bessel function at different points

There is no direct function to calculate the value of the derivatives of a Bessel Function, however, one can use the following identity to get it:

 J(s-1)(z) - J(s+1)(z)  = 2J'(s)(z)

where s, s-1 and s+1 are the orders of the Bessel function and z is the point of evaluation. One can use similar identities for Hankel functions.

MATLAB: Matlab Numerical integral improvement

Updated answer for R2017b. Use int and convert the symbolic solution to floating point.

>> syms x
f = int(besselj(1, x/2)*besselj(1, (7*x)/2),x,0,inf)
f =
-(4*(100*ellipticE(1/49) - 99*ellipticK(1/49)))/(21*pi)
>> f_dbl = double(ans)
f_dbl =
    0.0022
>> f_vpa = vpa(f)
f_vpa =
0.0022054352588140668793354496265733

OLD ANSWER from 13-Feb-2017

Try using "vpaintegral": https://www.mathworks.com/help/symbolic/vpaintegral.html#bvaajp9-1

The convert to double using "double".

Best Answer

Related Solutions

MATLAB: How to evaluate the derivatives of a Bessel function at different points

MATLAB: Matlab Numerical integral improvement

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