Adding support for multiple bar plots

Author: v0dro

lib/rubyplot/artist/axes.rb

@@ -20,18 +20,9 @@ class Axes < Base
       attr_accessor :x_range
       # Range of Y axis.
       attr_accessor :y_range,
-                    :x_tick_count, :y_tick_count, :text_font, :grid,
+                    :text_font, :grid,
                     :bounding_box, :x_axis_padding, :y_axis_padding, :origin,
                     :title_shift, :title_margin
-
-      # A hash of names for the individual columns, where the key is the array
-      # index for the column this label represents.
-      #
-      # Not all columns need to be named.
-      #
-      # Example: 0 => 2005, 3 => 2006, 5 => 2007, 7 => 2008
-      attr_accessor :x_ticks
-      attr_accessor :y_ticks
       # Main title for this Axes.
       attr_accessor :title
       # Rubyplot::Figure object to which this Axes belongs.
@@ -71,8 +62,6 @@ def initialize figure
         @y_axis_margin = 40.0
         @x_range = [nil, nil]
         @y_range = [nil, nil]
-        @x_tick_count = :default
-        @y_tick_count = :default
 
         @origin = [nil, nil]
         @title = ""
@@ -81,7 +70,6 @@ def initialize figure
         @text_font = :default
         @grid = true
         @bounding_box = true
-        @x_ticks = {}
         @plots = []
 
         @raw_rows = width * (height/width)
@@ -124,6 +112,7 @@ def legend_box_iy
 
       # Write an image to a file by communicating with the backend.
       def draw
+        consolidate_plots
         configure_title
         calculate_xy_axes_origin
         configure_xy_axes
@@ -191,6 +180,10 @@ def height
         (1 - (@figure.top_spacing + @figure.bottom_spacing)) * @figure.height
       end
 
+      def x_ticks= ticks_hash
+        @x_ticks = ticks_hash
+      end
+
       private
 
       def add_plot plot_type, *args, &block
@@ -300,6 +293,12 @@ def label_string(value, increment)
         parts[0].gsub!(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1#{THOUSAND_SEPARATOR}")
         parts.join('.')
       end
+
+      def consolidate_plots
+        bars = @plots.map { |p| p.is_a?(Rubyplot::Artist::Plot::Bar) }
+        @plots.delete_if { |p| p.is_a?(Rubyplot::Artist::Plot::Bar) }
+        @plots << Rubyplot::Artist::Plot::MultiBars.new(self, bars)
+      end
     end # class Axes
   end # moudle Artist
 end # module Rubyplot

lib/rubyplot/artist/axis/base.rb

@@ -7,7 +7,7 @@ class Base
 
         attr_reader :label, :ticks, :major_ticks_count, :min_val, :max_val, :title
         attr_reader :abs_x1, :abs_x2, :abs_y1, :abs_y2, :backend
-        attr_reader :stroke_width
+        attr_reader :stroke_width, :major_ticks
 
         def initialize axes, title, min_val, max_val
           @axes = axes
@@ -16,6 +16,7 @@ def initialize axes, title, min_val, max_val
           @max_val = max_val
           @stroke_width = 1.0
           @backend = @axes.backend
+          @major_ticks = []
         end
       end # class Base
     end # class Axis

lib/rubyplot/artist/axis/x_axis.rb

@@ -11,7 +11,6 @@ def initialize(*)
         @abs_y2 = @axes.origin[1]
         @major_ticks_count = 5
         @major_ticks_distance = (@abs_x2 - @abs_x1) / @major_ticks_count
-        @x_ticks = []
         configure_axis_line
         populate_major_x_ticks
         configure_title
@@ -35,7 +34,7 @@ def populate_major_x_ticks
         value_distance = (@max_val) / @major_ticks_count.to_f
         @major_ticks_count.times do |count|
           count += 1
-          @x_ticks << Rubyplot::Artist::XTick.new(
+          @major_ticks << Rubyplot::Artist::XTick.new(
             @axes,
             abs_x: count * @major_ticks_distance + @abs_x1,
             abs_y: @abs_y1,

lib/rubyplot/artist/plot/bar.rb

@@ -4,25 +4,52 @@ module Plot
       class Bar < Artist::Plot::Base
         # Space between the columns.
         attr_accessor :bar_spacing
+        # Width of each bar.
+        attr_accessor :bar_width
         # Number between 0 and 1.0 denoting spacing between the bars.
         # 0.0 means no spacing at all 1.0 means that each bars' width
         # is nearly 0 (so each bar is a simple line with no X dimension).
-        attr_reader :spacing_factor
+        attr_reader :spacing_ratio
         def initialize(*)
           super
-          @spacing_factor = 0.9
+          @spacing_ratio = 0.1
         end
 
         # Set the spacing factor for this bar plot.
-        def spacing_factor= sf
-          raise ValueError, '@spacing_factor must be between 0.00 and 1.00' unless
+        def spacing_ratio= sf
+          raise ValueError, '@spacing_ratio must be between 0.00 and 1.00' unless
             (sf >= 0) && (sf <= 1)
-          @spacing_factor = sf
+          @spacing_ratio = sf
         end
-        
+
+        # Set Bar plot data.
+        def data y_values
+          @data[:y_values] = y_values
+          set_yrange
+        end
+
+        # Number of bars in this Bar plot
+        def num_bars
+          @data[:y_values].size
+        end
+
         def draw
           super
           return unless @axes.geometry.has_data
+          configure_bars
+        end
+
+        private
+
+        # FIXME: handle positive and negative bars.
+        def configure_bars
+          x_axis_length = @axes.x_axis.abs_x2 - @axes.x_axis.abs_x1
+          @bar_width = coords_width / @data[:y_values].to_f
+          padding = @bar_width * @spacing_ratio / 2
+          @normalized_data[:y_values].each_with_index do |iy, index|
+            ix = @normalized_data[:x_values][index]
+            left_x = ix * x_axis_length 
+          end
         end
       end # class Bar
     end # module Plot

lib/rubyplot/artist/plot/base.rb

@@ -42,14 +42,8 @@ def data x_values, y_values
           # Set column count if this is larger than previous column counts
           @axes.geometry.column_count = y_values.length > @axes.geometry.column_count ?
                                      y_values.length : @axes.geometry.column_count
-          if @axes.y_range[0].nil? && @axes.y_range[1].nil?
-            @axes.y_range[0] = y_values.min
-            @axes.y_range[1] = y_values.max
-          end
-          if @axes.x_range[1].nil? && @axes.x_range[0].nil?
-            @axes.x_range[0] = x_values.min
-            @axes.x_range[1] = x_values.max
-          end
+          set_yrange
+          set_xrange
           @axes.geometry.has_data = true
         end
 
@@ -61,9 +55,25 @@ def normalize
           y_spread = @axes.y_range[1] - y_min
           @normalized_data[:x_values] = @data[:x_values].map do |x|
             (x.to_f - x_min) / x_spread 
-          end
+          end if @data[:x_values]
           @normalized_data[:y_values] = @data[:y_values].map do |y|
             (y.to_f - y_min) / y_spread
+          end if @data[:y_values]
+        end
+
+        protected
+
+        def set_xrange
+          if @axes.x_range[1].nil? && @axes.x_range[0].nil?
+            @axes.x_range[0] = @data[:x_values].min
+            @axes.x_range[1] = @data[:x_values].max
+          end
+        end
+
+        def set_yrange
+          if @axes.y_range[0].nil? && @axes.y_range[1].nil?
+            @axes.y_range[0] = @data[:y_values].min
+            @axes.y_range[1] = @data[:y_values].max
           end
         end
       end # class Base

lib/rubyplot/artist/plot/multi_bars.rb

@@ -0,0 +1,45 @@
+module Rubyplot
+  module Artist
+    module Plot
+      # Class for holding multiple Bar plot objects.
+      class MultiBars < Artist::Plot::Base
+        # The max. width that each bar can occupy.
+        attr_reader :max_bar_width
+        
+        def initialize(*, bar_plots:)
+          super
+          @bar_plots = bar_plots
+        end
+
+        def draw
+          configure_plot_geometry_data
+          configure_x_ticks
+          broadcast_to_bar_plots
+          @bar_plots.each(&:draw)
+        end
+
+        private
+
+        def configure_plot_geometry_data
+          max_bars = @bar_plots.map { |bar| bar.num_bars }.max
+          @max_bar_width = (@axes.x_axis.abs_x2 - @axes.x_axis.abs_x1).abs
+          @bar_plots.each do |bar|
+            set_bar_coords bar
+          end
+        end
+         
+        def configure_x_ticks
+          if @axes.x_ticks # user supplied ticks
+            
+          else # default ticks
+            
+          end
+        end
+
+        def set_bar_coords bar_plot
+          
+        end
+      end # class MultiBars
+    end # module Plot
+  end # module Artist
+end # module Rubyplot

spec/axes_spec.rb

@@ -449,11 +449,10 @@
         #        FileUtils.rm_rf SPEC_ROOT + "temp/bar"
       end
 
-      it "adds a simple bar plot" do
+      it "adds a simple bar plot", focus: true do
         fig = Rubyplot::Figure.new
         axes = fig.add_subplot 0,0
         axes.bar!(600) do |p| 
-          p.marker_count = 8
           p.data [5,12,9,6,7]
           p.label = "data"
           p.color = :yellow
@@ -523,7 +522,7 @@
         # expect(@temp_dir + file).to eq_image(@fix_dir + file)
       end
 
-       skip "adds multiple bar plots for wide graph" do
+       skip "adds multiple bar plots for wide graph", focus: true do
         fig = Rubyplot::Figure.new
         axes = fig.add_subplot 0,0
         data.each do |name, nums|