C:\perlp>812293.pl
Organism  Frequency Median_Eval      Median_Contig_Length Median_Mapped_Length
organism2 4         5.000000005e-103 122                  46
organism1 2         0.055            122                  45
organism4 2         6.5              188                  50
organism3 1         1e-2             155                  90