Question: To calculate the derivative of Bessel

I want  to calculate the derivative of Bessel, I do

hh := proc (`&varpi;`) options operator, arrow; (`&varpi;`-V*m*Pi/LL)^2/C[f]^2-m^2*Pi^2/LL^2 end proc; H := proc (`&varpi;`) options operator, arrow; piecewise(0 <= hh(`&varpi;`), sqrt(hh(`&varpi;`)), hh(`&varpi;`) < 0, sqrt(-hh(`&varpi;`))) end proc; Y := proc (`&varpi;`) options operator, arrow; piecewise(0 <= hh(`&varpi;`), BesselJ(n, R*sqrt(hh(`&varpi;`))), hh(`&varpi;`) < 0, BesselI(n, R*sqrt(-hh(`&varpi;`)))) end proc; YY := proc (`&varpi;`, z) options operator, arrow; piecewise(0 <= hh(`&varpi;`), BesselJ(n, z), hh(`&varpi;`) < 0, BesselI(n, z)) end proc; www := proc (`&varpi;`) options operator, arrow; (D[2](YY))(`&varpi;`, R*sqrt(hh(`&varpi;`))) end proc; PF := proc (`&varpi;`) options operator, arrow; rho[f]*(`&varpi;`-V*m*Pi/LL)^2*Y(`&varpi;`)/(H(`&varpi;`)*www(`&varpi;`)) end proc

Is it right or not?

Thank you very much!