# File lib/mongrel/stats.rb, line 75
75:   def sd
76:     # (sqrt( ((s).sumsq - ( (s).sum * (s).sum / (s).n)) / ((s).n-1) ))
77:     begin
78:       return Math.sqrt( (@sumsq - ( @sum * @sum / @n)) / (@n-1) )
79:     rescue Errno::EDOM
80:       return 0.0
81:     end
82:   end