ozly
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Hi zorro,
what if "z" is also a function of two variables, for example, z(x,y)? thanks...
Hi,
Exact formulas for the derivatives can be obtained symbolically. With symbolic toolbox in Matlab, the following lines give it for the first kind (put besselk for the second kind):
syms z;
syms nu;
diff(besselj(nu,z),z)
The results are:
-besselj(nu+1,z)+nu/z*besselj(nu,z)
-besselk(nu+1,z)+nu/z*besselk(nu,z)
(The same can be found in math books or tables.)
Then, use built-in besselj and besselk functions.
I hope this is what you need.
Regards
Z
what if "z" is also a function of two variables, for example, z(x,y)? thanks...
Hi,
Exact formulas for the derivatives can be obtained symbolically. With symbolic toolbox in Matlab, the following lines give it for the first kind (put besselk for the second kind):
syms z;
syms nu;
diff(besselj(nu,z),z)
The results are:
-besselj(nu+1,z)+nu/z*besselj(nu,z)
-besselk(nu+1,z)+nu/z*besselk(nu,z)
(The same can be found in math books or tables.)
Then, use built-in besselj and besselk functions.
I hope this is what you need.
Regards
Z