Using FindRoot in complex funtion

*To*: mathgroup at smc.vnet.net*Subject*: [mg71900] Using FindRoot in complex funtion*From*: "tatsec" <markelbbs at tom.com>*Date*: Sun, 3 Dec 2006 06:26:14 -0500 (EST)

The program is : dotnum=40; sigma=Sqrt[2]; For[L=2,L<=dotnum,L=L+2, FindRoot[Integrate[2^(1/2-L/2)*sigma^(-1-L)*(Abs[t])^(1/2*(-1-L))*BesselK[(1-L)/2,Abs[t]/sigma]/(Sqrt[pi]*Gamma[L/2]),{t,0,y}],{y,1}];] when L<30, FindRoot can find the root of function.but L=>30,FindRoot can't calculation.So How to solve this problem? Thanks in advance for any help you can give me. Raymond