refactored the nearby method into it's own module

lib/edge_detect.rb

@@ -2,6 +2,7 @@ require 'chunky_png'
 require 'matrix'
 
 require 'edge_detect/version'
+require 'edge_detect/nearby'
 require 'edge_detect/matrix'
 require 'edge_detect/gray_scaler'
 require 'edge_detect/differ'
@@ -12,6 +13,6 @@ require 'edge_detect/sobel_edge_detector'
 
 ##
 # EdgeDetection module
-# 
+#
 module EdgeDetect
-end
+end

lib/edge_detect/differ.rb

@@ -1,14 +1,15 @@
 module EdgeDetect
-  
-  ## 
-  # Abstract base class that provides the basis for both, 
+
+  ##
+  # Abstract base class that provides the basis for both,
   # the horizontal and vertical differ.
   #
   class Differ
+    include Nearby
 
-    ## 
+    ##
     # Initializes a new differ with a given image
-    # 
+    #
     # @param image [ChunkyPNG::Image] the image that should be diffed
     #
     def initialize(image)
@@ -16,33 +17,14 @@ module EdgeDetect
       @gray_scaler = GrayScaler.new(image)
     end
 
-    ## 
+    ##
     # Should return the diffed value of the given pixel.
     # If the pixel is out of bounds 0 should be returned.
-    # 
+    #
     # @return [Integer] a value between 0 and 255 representing a grayscale value.
     #
     def [](x, y)
       raise NotImplementedError
     end
-
-    ##
-    # Returns the nearby diffs of the given coordinates (x, y) with respect to 
-    # the given radius.
-    #
-    # @return [Array<Array<Integer>>] a two dimensional array with the diffs.
-    #
-    def nearby(x, y, radius)
-      output = []
-      ((x - radius)..(x + radius)).each do |i|
-        row = []
-        ((y - radius)..(y + radius)).each do |j|
-          row << self[i, j] 
-        end
-        output << row
-      end
-      output
-    end
-   
   end
 end

lib/edge_detect/gray_scaler.rb

@@ -1,10 +1,10 @@
 module EdgeDetect
   ##
   # Grayscales a given image
-  # 
+  #
   class GrayScaler
-
-    ## 
+    include Nearby
+    ##
     # Initializes a new GrayScaler with the given image
     #
     # @param image [ChunkyPNG::Image] the image that should be grayscaled.
@@ -13,8 +13,8 @@ module EdgeDetect
       @image = image
     end
 
-    ## 
-    # Returns the grayscale value of the given coordinate. 
+    ##
+    # Returns the grayscale value of the given coordinate.
     # If the coordinate is out of bounds 0 will be returned.
     #
     # @return [Integer] a value between 0 and 255.
@@ -26,24 +26,5 @@ module EdgeDetect
         0
       end
     end
-
-    ##
-    # Returns the nearby grayscale values of the given coordinates (x, y) with 
-    # respect to the given radius.
-    #
-    # @return [Array<Array<Integer>>] a two dimensional array with the grayscale values.
-    #
-    def nearby(x, y, radius)
-      output = []
-      ((x - radius)..(x + radius)).each do |i|
-        row = []
-        ((y - radius)..(y + radius)).each do |j|
-          row << self[i, j] 
-        end
-        output << row
-      end
-      output
-    end
-
   end
 end

lib/edge_detect/nearby.rb

@@ -0,0 +1,26 @@
+module EdgeDetect
+  ##
+  # The nearby module provides a method that uses the [x, y] method
+  # to query a two dimensional array.
+  #
+  module Nearby
+
+    ##
+    # Returns the nearby values of the given coordinates (x, y) with respect to
+    # the given radius.
+    #
+    # @return [Array<Array<Value>>] a two dimensional array with the Values.
+    #
+    def nearby(x, y, radius)
+      output = []
+      ((x - radius)..(x + radius)).each do |i|
+        row = []
+        ((y - radius)..(y + radius)).each do |j|
+          row << self[i, j]
+        end
+        output << row
+      end
+      output
+    end
+  end
+end

lib/edge_detect/sobel_edge_detector.rb

@@ -7,9 +7,9 @@ module EdgeDetect
 
     ##
     # Edge detects the image by applying the sobel operations.
-    # 
+    #
     # The original image will not be changed by this operation.
-    # 
+    #
     # @return [ChunkyPNG::Image] the edge detected image.
     #
     def detect_edges
@@ -31,7 +31,7 @@ module EdgeDetect
 
     private
 
-      ## 
+      ##
       # The sobel matrix to transform horizontal pixels
       #
       # @return [Matrix] the sobel matrix
@@ -44,7 +44,7 @@ module EdgeDetect
         ]
       end
 
-      ## 
+      ##
       # The sobel matrix to transform vertical pixels
       #
       # @return [Matrix] the sobel matrix