Fixed annoying Enumerable issue - now we can drop use of to_a in Ruby…

… 1.9+

README.md

@@ -211,7 +211,7 @@ gem
     gem install statsample
 ```
 
-(statsample is not loaded by default, as it has a host of
+(statsample is not loaded by default because it has a host of
 dependencies)
 
 Thereafter, to calculate the stats for columns 1 and 2 (rowname is column 0)

lib/bio-table/filter.rb

@@ -1,6 +1,10 @@
 module BioTable
 
+  # LazyValues fetches values on demand from the @fields array. In the [] method
+  # a field is transformed into a float when it is called.
+
   class LazyValues
+
     include Enumerable
 
     def initialize fields
@@ -16,12 +20,16 @@ def [] index
       @values[index]
     end
 
-    def each
-      @fields.each_with_index do | field, i |
-        yield self[i]
+    def each &block
+      @fields.each_with_index do |field,i|
+        if block_given?
+          block.call self[i]
+        else
+          yield self[i]
+        end
       end
     end
-
+  
     def compact
       a = []
       each do | e |

lib/bio-table/statistics.rb

@@ -3,7 +3,12 @@ module BioTable
 
   module Statistics
 
-require 'statsample'
+begin
+  require 'statsample'
+rescue LoadError
+  $stderr.print "Error: Missing statsample. Install with command 'gem install statsample'\n"
+  exit 1
+end
 
     attr_reader :columns