程序运行中无报错，但是输出的figtree里面分化时间是NAN。如下：UTREE 1 = (((Spermwhale: -nan, (Cow: -nan, Sheep: -nan)。我用seq模式和近似自然法都是同样的情况，我的序列是cds序列，我输入的树文件是：(((A,(C,S)'U(0.15)')'B(0.47,0.58)',((((B,LA),BK),DR),(H,W))),Ho)'B(0.728,0.783)';我的控制文件如下，请问是哪里出了问题：

seed = -1

       seqfile = single_copy.cds_msa_trimed.phy

      treefile = input.tree

       outfile = out

         ndata = 1

       seqtype = 0  * 0: nucleotides; 1:codons; 2:AAs

       usedata = 1    * 0: no data; 1:seq like; 2:use in.BV; 3: out.BV

         clock = 3    * 1: global clock; 2: independent rates; 3: correlated rates

       RootAge = <0.9  * safe constraint on root age, used if no fossil for root.

         model = 4    * 0:JC69, 1:K80, 2:F81, 3:F84, 4:HKY85

         alpha = 0.5    * alpha for gamma rates at sites

         ncatG = 5    * No. categories in discrete gamma

     cleandata = 0    * remove sites with ambiguity data (1:yes, 0:no)?

       BDparas = 1 1 0    * birth, death, sampling

   kappa_gamma = 6 2      * gamma prior for kappa

   alpha_gamma = 1 1      * gamma prior for alpha

   rgene_gamma = 1 112   * gamma prior for overall rates for genes

  sigma2_gamma = 1 10    * gamma prior for sigma^2     (for clock=2 or 3)

      finetune = 1: 0.1  0.1  0.1  0.01 .5  * auto (0 or 1) : times, musigma2, rates, mixing, paras, FossilErr

         print = 1

        burnin = 25000000

      sampfreq = 1000

       nsample = 50000000