--- oldarray.c	2009-10-31 19:58:22.000000000 -0400
+++ array.c	2009-10-31 19:44:04.000000000 -0400
@@ -43,6 +43,7 @@
     }
 }
 
+
 # define ARY_SHARED_P(ary) \
     (assert(!FL_TEST(ary, ELTS_SHARED) || !FL_TEST(ary, RARRAY_EMBED_FLAG)), \
      FL_TEST(ary,ELTS_SHARED)!=0)
@@ -1406,6 +1407,55 @@
 
 /*
  *  call-seq:
+ *  		array.sum	->	double
+ *
+ *  Finds the sum of all the values in <i>self</i>.
+ *  All of the values must be numbers, 
+ *  otherwise, the function raises a TypeError.
+ * 
+ *  a = [1, 2, 3]
+ *  a.sum	#=>		6
+ *
+ *  
+*/
+
+static VALUE
+rb_ary_sum(VALUE ary)
+{
+	long i;
+	double sum = 0.0;
+	
+	
+	for (i=0; i<RARRAY_LEN(ary); i++) {
+	if( TYPE(RARRAY_PTR(ary)[i]) == T_STRING) {
+		rb_raise(rb_eTypeError, "Element is not a number!");
+	} else {
+		sum = sum +  NUM2DBL(RARRAY_PTR(ary)[i]);
+	}
+	}
+	return DBL2NUM(sum);
+}
+
+/*
+ * call-seq:
+ * 		array.mean	->	double
+ *
+ *  Finds the mean of values in <i>self</i>. All values must be numbers,
+ *  otherwise, the function raises a TypeError.
+ *
+ *  a = [1, 2, 3]
+ *  a.mean	#=>		2
+ *
+ */
+	
+static VALUE
+rb_ary_mean(VALUE ary)
+{
+	return DBL2NUM(NUM2DBL(rb_ary_sum(ary)) / RARRAY_LEN(ary));	
+}
+
+/*
+ *  call-seq:
  *     array.each_index {|index| block }  ->  array
  *
  *  Same as <code>Array#each</code>, but passes the index of the element
@@ -4151,6 +4201,9 @@
     rb_define_method(rb_cArray, "take_while", rb_ary_take_while, 0);
     rb_define_method(rb_cArray, "drop", rb_ary_drop, 1);
     rb_define_method(rb_cArray, "drop_while", rb_ary_drop_while, 0);
+    
+    rb_define_method(rb_cArray, "sum", rb_ary_sum, 0);
+    rb_define_method(rb_cArray, "mean", rb_ary_mean, 0);
 
     id_cmp = rb_intern("<=>");
 }