Fixed LineChart and refactored chart axes management

12 files changed, 181 insertions, 131 deletions

diff --git a/lib/axlsx/drawing/axes.rb b/lib/axlsx/drawing/axes.rb
new file mode 100644
index 00000000..99565cb6
--- /dev/null
+++ b/lib/axlsx/drawing/axes.rb
@@ -0,0 +1,40 @@
+module Axlsx
+
+  class Axes
+
+    def initialize(options={})
+      options.each do |name, axis_class|
+        add_axis(name, axis_class)
+      end
+    end
+
+    def [](name)
+      axes.assoc(name)[1]
+    end
+
+    def to_xml_string(str = '', options = {})
+      if options[:ids]
+        axes.inject(str) { |string, axis| string << '<c:axId val="' << axis[1].id.to_s << '"/>' }
+      else
+        axes.each { |axis| axis[1].to_xml_string(str) }
+      end
+    end
+
+    def add_axis(name, axis_class)
+      axis = axis_class.new
+      set_cross_axis(axis)
+      axes << [name, axis]
+    end
+
+    private
+
+    def axes
+      @axes ||= []
+    end
+
+    def set_cross_axis(axis)
+      axes.first[1].cross_axis = axis if axes.size == 1
+      axis.cross_axis = axes.first[1] unless axes.empty?
+    end
+  end
+end
diff --git a/lib/axlsx/drawing/axis.rb b/lib/axlsx/drawing/axis.rb
index 1b55bece..16c087a2 100644
--- a/lib/axlsx/drawing/axis.rb
+++ b/lib/axlsx/drawing/axis.rb
@@ -7,17 +7,13 @@ module Axlsx
     include Axlsx::OptionsParser
 
     # Creates an Axis object
-    # @param [Integer] ax_id the id of this axis
-    # @param [Integer] cross_ax the id of the perpendicular axis
+    # @param [Integer] cross_axis the perpendicular axis
     # @option options [Symbol] ax_pos
     # @option options [Symbol] crosses
     # @option options [Symbol] tick_lbl_pos
     # @raise [ArgumentError] If axi_id or cross_ax are not unsigned integers
-    def initialize(ax_id, cross_ax, options={})
-      Axlsx::validate_unsigned_int(ax_id)
-      Axlsx::validate_unsigned_int(cross_ax)
-      @ax_id = ax_id
-      @cross_ax = cross_ax
+    def initialize(options={})
+      @id = rand(8 ** 8)
       @format_code = "General"
       @delete = @label_rotation = 0
       @scaling = Scaling.new(:orientation=>:minMax)
@@ -37,13 +33,13 @@ module Axlsx
 
     # the id of the axis.
     # @return [Integer]
-    attr_reader :ax_id
-    alias :axID :ax_id
+    attr_reader :id
+    alias :axID :id
 
     # The perpendicular axis
     # @return [Integer]
-    attr_reader :cross_ax
-    alias :crossAx :cross_ax
+    attr_reader :cross_axis
+    alias :crossAx :cross_axis
 
     # The scaling of the axis
     # @see Scaling
@@ -95,6 +91,11 @@ module Axlsx
       @color = color_rgb
     end
 
+    def cross_axis=(axis)
+       DataTypeValidator.validate "#{self.class}.cross_axis", [Axis], axis
+       @cross_axis = axis
+    end
+
     # The position of the axis
     # must be one of [:l, :r, :t, :b]
     def ax_pos=(v) RestrictionValidator.validate "#{self.class}.ax_pos", [:l, :r, :b, :t], v; @ax_pos = v; end
@@ -147,7 +148,7 @@ module Axlsx
     # @param [String] str
     # @return [String]
     def to_xml_string(str = '')
-      str << '<c:axId val="' << @ax_id.to_s << '"/>'
+      str << '<c:axId val="' << @id.to_s << '"/>'
       @scaling.to_xml_string str
       str << '<c:delete val="'<< @delete.to_s << '"/>'
       str << '<c:axPos val="' << @ax_pos.to_s << '"/>'
@@ -175,7 +176,7 @@ module Axlsx
       end
       # some potential value in implementing this in full. Very detailed!
       str << '<c:txPr><a:bodyPr rot="' << @label_rotation.to_s << '"/><a:lstStyle/><a:p><a:pPr><a:defRPr/></a:pPr><a:endParaRPr/></a:p></c:txPr>'
-      str << '<c:crossAx val="' << @cross_ax.to_s << '"/>'
+      str << '<c:crossAx val="' << @cross_axis.id.to_s << '"/>'
       str << '<c:crosses val="' << @crosses.to_s << '"/>'
     end
 
diff --git a/lib/axlsx/drawing/bar_3D_chart.rb b/lib/axlsx/drawing/bar_3D_chart.rb
index 6f69f703..0e2b37bb 100644
--- a/lib/axlsx/drawing/bar_3D_chart.rb
+++ b/lib/axlsx/drawing/bar_3D_chart.rb
@@ -10,12 +10,16 @@ module Axlsx
 
     # the category axis
     # @return [CatAxis]
-    attr_reader :cat_axis
+    def cat_axis
+      axes[:cat_axis]
+    end
     alias :catAxis :cat_axis
 
     # the value axis
     # @return [ValAxis]
-    attr_reader :val_axis
+    def val_axis
+      axes[:val_axis]
+    end
     alias :valAxis :val_axis
 
     # The direction of the bars in the chart
@@ -75,10 +79,6 @@ module Axlsx
     def initialize(frame, options={})
       @vary_colors = true
       @gap_width, @gap_depth, @shape = nil, nil, nil
-      @cat_ax_id = rand(8 ** 8)
-      @val_ax_id = rand(8 ** 8)
-      @cat_axis = CatAxis.new(@cat_ax_id, @val_ax_id)
-      @val_axis = ValAxis.new(@val_ax_id, @cat_ax_id, :tick_lbl_pos => :low, :ax_pos => :l)
       super(frame, options)
       @series_type = BarSeries
       @view_3D = View3D.new({:r_ang_ax=>1}.merge(options))
@@ -131,17 +131,18 @@ module Axlsx
         str_inner << '<c:grouping val="' << grouping.to_s << '"/>'
         str_inner << '<c:varyColors val="' << vary_colors.to_s << '"/>'
         @series.each { |ser| ser.to_xml_string(str_inner) }
-        @d_lbls.to_xml_string(str) if @d_lbls
+        @d_lbls.to_xml_string(str_inner) if @d_lbls
         str_inner << '<c:gapWidth val="' << @gap_width.to_s << '"/>' unless @gap_width.nil?
         str_inner << '<c:gapDepth val="' << @gap_depth.to_s << '"/>' unless @gap_depth.nil?
         str_inner << '<c:shape val="' << @shape.to_s << '"/>' unless @shape.nil?
-        str_inner << '<c:axId val="' << @cat_ax_id.to_s << '"/>'
-        str_inner << '<c:axId val="' << @val_ax_id.to_s << '"/>'
-        str_inner << '<c:axId val="0"/>'
+        axes.to_xml_string(str_inner, :ids => true)
         str_inner << '</c:bar3DChart>'
-        @cat_axis.to_xml_string str_inner
-        @val_axis.to_xml_string str_inner
+        axes.to_xml_string(str_inner)
       end
     end
+
+    def axes
+     @axes ||= Axes.new(:val_axis => ValAxis, :cat_axis => CatAxis)
+    end
   end
 end
diff --git a/lib/axlsx/drawing/cat_axis.rb b/lib/axlsx/drawing/cat_axis.rb
index ba392ce6..f32c23c9 100644
--- a/lib/axlsx/drawing/cat_axis.rb
+++ b/lib/axlsx/drawing/cat_axis.rb
@@ -4,23 +4,15 @@ module Axlsx
   class CatAxis < Axis
 
     # Creates a new CatAxis object
-    # @param [Integer] ax_id the id of this axis. Inherited
-    # @param [Integer] cross_ax the id of the perpendicular axis. Inherited
-    # @option options [Symbol] ax_pos. Inherited
-    # @option options [Symbol] tick_lbl_pos. Inherited
-    # @option options [Symbol] crosses. Inherited
-    # @option options [Boolean] auto
-    # @option options [Symbol] lbl_algn
-    # @option options [Integer] lbl_offset
     # @option options [Integer] tick_lbl_skip
     # @option options [Integer] tick_mark_skip
-    def initialize(ax_id, cross_ax, options={})
+    def initialize(options={})
       @tick_lbl_skip = 1
       @tick_mark_skip = 1
       self.auto = 1
       self.lbl_algn = :ctr
       self.lbl_offset = "100"
-      super(ax_id, cross_ax, options)
+      super(options)
     end
 
     # From the docs: This element specifies that this axis is a date or text axis based on the data that is used for the axis labels, not a specific choice.
diff --git a/lib/axlsx/drawing/d_lbls.rb b/lib/axlsx/drawing/d_lbls.rb
index 3685e7d2..74c01350 100644
--- a/lib/axlsx/drawing/d_lbls.rb
+++ b/lib/axlsx/drawing/d_lbls.rb
@@ -10,7 +10,7 @@ module Axlsx
     include Axlsx::OptionsParser 
     # creates a new DLbls object
     def initialize(chart_type, options={})
-      raise ArgumentError, 'chart_type must inherit from Chart' unless chart_type.superclass == Chart
+      raise ArgumentError, 'chart_type must inherit from Chart' unless [Chart, LineChart].include?(chart_type.superclass)
       @chart_type = chart_type
       initialize_defaults
       parse_options options
diff --git a/lib/axlsx/drawing/drawing.rb b/lib/axlsx/drawing/drawing.rb
index 7567dea1..58f0f81e 100644
--- a/lib/axlsx/drawing/drawing.rb
+++ b/lib/axlsx/drawing/drawing.rb
@@ -22,6 +22,7 @@ module Axlsx
   require 'axlsx/drawing/ser_axis.rb'
   require 'axlsx/drawing/cat_axis.rb'
   require 'axlsx/drawing/val_axis.rb'
+  require 'axlsx/drawing/axes.rb'
 
   require 'axlsx/drawing/marker.rb'
 
diff --git a/lib/axlsx/drawing/line_3D_chart.rb b/lib/axlsx/drawing/line_3D_chart.rb
index 627cfe83..183f3250 100644
--- a/lib/axlsx/drawing/line_3D_chart.rb
+++ b/lib/axlsx/drawing/line_3D_chart.rb
@@ -11,7 +11,7 @@ module Axlsx
   #   ws = p.workbook.add_worksheet
   #   ws.add_row ["This is a chart with no data in the sheet"]
   #
-  #   chart = ws.add_chart(Axlsx::Line3DChart, :start_at=> [0,1], :end_at=>[0,6], :title=>"Most Popular Pets")
+  #   chart = ws.add_chart(Axlsx::Line3DChart, :start_at=> [0,1], :end_at=>[0,6], :t#itle=>"Most Popular Pets")
   #   chart.add_series :data => [1, 9, 10], :labels => ["Slimy Reptiles", "Fuzzy Bunnies", "Rottweiler"]
   #
   # @see Worksheet#add_chart
@@ -19,48 +19,50 @@ module Axlsx
   # @see Chart#add_series
   # @see Series
   # @see Package#serialize
-  class Line3DChart < LineChart
+  class Line3DChart < Axlsx::LineChart
 
     # space between bar or column clusters, as a percentage of the bar or column width.
     # @return [String]
-    attr_reader :gapDepth
+    attr_reader :gap_depth
+    alias :gapDepth :gap_depth
 
     # validation regex for gap amount percent
     GAP_AMOUNT_PERCENT = /0*(([0-9])|([1-9][0-9])|([1-4][0-9][0-9])|500)%/
 
+    # the category axis
+    # @return [Axis]
+    def ser_axis
+      axes[:ser_axis]
+    end
+    alias :serAxis :ser_axis
+
     # Creates a new line chart object
-    # @param [GraphicFrame] frame The workbook that owns this chart.
-    # @option options [Cell, String] title
-    # @option options [Boolean] show_legend
-    # @option options [Symbol] grouping
-    # @option options [String] gapDepth
-    # @option options [Integer] rotX
-    # @option options [String] hPercent
-    # @option options [Integer] rotY
-    # @option options [String] depthPercent
-    # @option options [Boolean] rAngAx
-    # @option options [Integer] perspective
+    # @option options [String] gap_depth
     # @see Chart
+    # @see lineChart
     # @see View3D
     def initialize(frame, options={})
-      @gapDepth = nil
+      @gap_depth = nil
+      @view_3D = View3D.new({:r_ang_ax=>1}.merge(options))
       super(frame, options)
-      @view_3D = View3D.new({:perspective=>30}.merge(options))
+      axes.add_axis :ser_axis, SerAxis
     end
 
+
     # @see gapDepth
-    def gapDepth=(v)
-      RegexValidator.validate "Bar3DChart.gapWidth", GAP_AMOUNT_PERCENT, v
-      @gapDepth=(v)
+    def gap_depth=(v)
+      RegexValidator.validate "Line3DChart.gapWidth", GAP_AMOUNT_PERCENT, v
+      @gap_depth=(v)
     end
+    alias :gapDepth= :gap_depth=
 
-    # Serializes the object
-    # @param [String] str
-    # @return [String]
-    def to_xml_string(str = '')
-      super(str) do |str_inner|
-        str_inner << '<c:gapDepth val="' << @gapDepth.to_s << '"/>' unless @gapDepth.nil?
+      # Serializes the object
+      # @param [String] str
+      # @return [String]
+      def to_xml_string(str = '')
+        super(str) do |str_inner|
+          str_inner << '<c:gapDepth val="' << @gap_depth.to_s << '"/>' unless @gap_depth.nil?
+        end
       end
-    end
   end
 end
diff --git a/lib/axlsx/drawing/line_chart.rb b/lib/axlsx/drawing/line_chart.rb
index 7bf925e6..afe6154e 100644
--- a/lib/axlsx/drawing/line_chart.rb
+++ b/lib/axlsx/drawing/line_chart.rb
@@ -23,17 +23,19 @@ module Axlsx
 
     # the category axis
     # @return [CatAxis]
-    attr_reader :catAxis
+    def cat_axis
+      axes[:cat_axis]
+    end
+    alias :catAxis :cat_axis
 
     # the category axis
     # @return [ValAxis]
-    attr_reader :valAxis
-
-    # the category axis
-    # @return [Axis]
-    attr_reader :serAxis
+    def val_axis
+      axes[:val_axis]
+    end
+    alias :valAxis :val_axis
 
-    # must be one of  [:percentStacked, :clustered, :standard, :stacked]
+     # must be one of  [:percentStacked, :clustered, :standard, :stacked]
     # @return [Symbol]
     attr_reader :grouping
 
@@ -46,12 +48,6 @@ module Axlsx
     def initialize(frame, options={})
       @vary_colors = false
       @grouping = :standard
-      @catAxId = rand(8 ** 8)
-      @valAxId = rand(8 ** 8)
-      @serAxId = rand(8 ** 8)
-      @catAxis = CatAxis.new(@catAxId, @valAxId)
-      @valAxis = ValAxis.new(@valAxId, @catAxId)
-      @serAxis = SerAxis.new(@serAxId, @valAxId)
       super(frame, options)
       @series_type = LineSeries
       @d_lbls = nil
@@ -59,29 +55,38 @@ module Axlsx
 
     # @see grouping
     def grouping=(v)
-      RestrictionValidator.validate "Bar3DChart.grouping", [:percentStacked, :standard, :stacked], v
+      RestrictionValidator.validate "LineChart.grouping", [:percentStacked, :standard, :stacked], v
       @grouping = v
     end
 
+    def node_name
+      path = self.class.to_s
+      if i = path.rindex('::')
+        path = path[(i+2)..-1]
+      end
+      path[0] = path[0].chr.downcase
+      path
+    end
+
     # Serializes the object
     # @param [String] str
     # @return [String]
     def to_xml_string(str = '')
       super(str) do |str_inner|
-        str_inner << "<c:#{self.class.name.demodulize.camelcase(:lower)}>"
+        str_inner << "<c:" << node_name << ">"
         str_inner << '<c:grouping val="' << grouping.to_s << '"/>'
         str_inner << '<c:varyColors val="' << vary_colors.to_s << '"/>'
         @series.each { |ser| ser.to_xml_string(str_inner) }
-        @d_lbls.to_xml_string(str) if @d_lbls
+        @d_lbls.to_xml_string(str_inner) if @d_lbls
         yield str_inner if block_given?
-        str_inner << '<c:axId val="' << @catAxId.to_s << '"/>'
-        str_inner << '<c:axId val="' << @valAxId.to_s << '"/>'
-        str_inner << '<c:axId val="' << @serAxId.to_s << '"/>'
-        str_inner << "</c:#{self.class.name.demodulize.camelcase(:lower)}>"
-        @catAxis.to_xml_string str_inner
-        @valAxis.to_xml_string str_inner
-        @serAxis.to_xml_string str_inner
+        axes.to_xml_string(str_inner, :ids => true)
+        str_inner << "</c:" << node_name << ">"
+        axes.to_xml_string(str_inner)
       end
     end
+
+    def axes
+      @axes ||= Axes.new(:cat_axis => CatAxis, :val_axis => ValAxis)
+    end
   end
 end
diff --git a/lib/axlsx/drawing/line_series.rb b/lib/axlsx/drawing/line_series.rb
index f70bdb49..467dcc2d 100644
--- a/lib/axlsx/drawing/line_series.rb
+++ b/lib/axlsx/drawing/line_series.rb
@@ -28,6 +28,7 @@ module Axlsx
     # @option options [Array, SimpleTypedList] labels
     # @param [Chart] chart
     def initialize(chart, options={})
+      @show_marker = false
       @labels, @data = nil, nil
       super(chart, options)
       @labels = AxDataSource.new(:data => options[:labels]) unless options[:labels].nil?
diff --git a/lib/axlsx/drawing/scatter_chart.rb b/lib/axlsx/drawing/scatter_chart.rb
index 2b801642..f069e346 100644
--- a/lib/axlsx/drawing/scatter_chart.rb
+++ b/lib/axlsx/drawing/scatter_chart.rb
@@ -12,35 +12,40 @@ module Axlsx
     # The Style for the scatter chart
     # must be one of :none | :line | :lineMarker | :marker | :smooth | :smoothMarker
     # return [Symbol]
-    attr_reader :scatterStyle
+    attr_reader :scatter_style
+    alias :scatterStyle :scatter_style
 
     # the x value axis
     # @return [ValAxis]
-    attr_reader :xValAxis
+    def x_val_axis
+      axes[:x_val_axis]
+    end
+    alias :xValAxis :x_val_axis
 
     # the y value axis
     # @return [ValAxis]
-    attr_reader :yValAxis
+    def y_val_axis
+      axes[:x_val_axis]
+    end
+    alias :yValAxis :y_val_axis
 
     # Creates a new scatter chart
     def initialize(frame, options={})
       @vary_colors = 0
-      @scatterStyle = :lineMarker
-      @xValAxId = rand(8 ** 8)
-      @yValAxId = rand(8 ** 8)
-      @xValAxis = ValAxis.new(@xValAxId, @yValAxId)
-      @yValAxis = ValAxis.new(@yValAxId, @xValAxId)
-      super(frame, options)
+      @scatter_style = :lineMarker
+
+           super(frame, options)
       @series_type = ScatterSeries
       @d_lbls = nil
       parse_options options
     end
 
     # see #scatterStyle
-    def scatterStyle=(v)
+    def scatter_style=(v)
       Axlsx.validate_scatter_style(v)
-      @scatterStyle = v
+      @scatter_style = v
     end
+    alias :scatterStyle= :scatter_style=
 
     # Serializes the object
     # @param [String] str
@@ -48,17 +53,19 @@ module Axlsx
     def to_xml_string(str = '')
       super(str) do |str_inner|
         str_inner << '<c:scatterChart>'
-        str_inner << '<c:scatterStyle val="' << scatterStyle.to_s << '"/>'
+        str_inner << '<c:scatterStyle val="' << scatter_style.to_s << '"/>'
         str_inner << '<c:varyColors val="' << vary_colors.to_s << '"/>'
         @series.each { |ser| ser.to_xml_string(str_inner) }
-        d_lbls.to_xml_string(str) if @d_lbls
-        str_inner << '<c:axId val="' << @xValAxId.to_s << '"/>'
-        str_inner << '<c:axId val="' << @yValAxId.to_s << '"/>'
+        d_lbls.to_xml_string(str_inner) if @d_lbls
+        axes.to_xml_string(str_inner, :ids => true)
         str_inner << '</c:scatterChart>'
-        @xValAxis.to_xml_string str_inner
-        @yValAxis.to_xml_string str_inner
+        axes.to_xml_string(str_inner)
       end
       str
     end
+
+    def axes
+      @axes ||= Axes.new(:x_val_axis => ValAxis, :y_val_axis => ValAxis)
+    end
   end
 end
diff --git a/lib/axlsx/drawing/ser_axis.rb b/lib/axlsx/drawing/ser_axis.rb
index 00b04989..54e2c60e 100644
--- a/lib/axlsx/drawing/ser_axis.rb
+++ b/lib/axlsx/drawing/ser_axis.rb
@@ -5,30 +5,29 @@ module Axlsx
 
     # The number of tick lables to skip between labels
     # @return [Integer]
-    attr_reader :tickLblSkip
+    attr_reader :tick_lbl_skip
+    alias :tickLblSkip :tick_lbl_skip
 
     # The number of tickmarks to be skipped before the next one is rendered.
     # @return [Boolean]
-    attr_reader :tickMarkSkip
+    attr_reader :tick_mark_skip
+    alias :tickMarkSkip :tick_mark_skip
 
     # Creates a new SerAxis object
-    # @param [Integer] axId the id of this axis. Inherited
-    # @param [Integer] crossAx the id of the perpendicular axis. Inherited
-    # @option options [Symbol] axPos. Inherited
-    # @option options [Symbol] tickLblPos. Inherited
-    # @option options [Symbol] crosses. Inherited
-    # @option options [Integer] tickLblSkip
-    # @option options [Integer] tickMarkSkip
-    def initialize(axId, crossAx, options={})
-      @tickLblSkip, @tickMarkSkip = 1, 1
-      super(axId, crossAx, options)
+    # @option options [Integer] tick_lbl_skip
+    # @option options [Integer] tick_mark_skip
+    def initialize(options={})
+      @tick_lbl_skip, @tick_mark_skip = 1, 1
+      super(options)
     end
 
     # @see tickLblSkip
-    def tickLblSkip=(v) Axlsx::validate_unsigned_int(v); @tickLblSkip = v; end
+    def tick_lbl_skip=(v) Axlsx::validate_unsigned_int(v); @tick_lbl_skip = v; end
+    alias :tickLblSkip= :tick_lbl_skip=
 
     # @see tickMarkSkip
-    def tickMarkSkip=(v) Axlsx::validate_unsigned_int(v); @tickMarkSkip = v; end
+    def tick_mark_skip=(v) Axlsx::validate_unsigned_int(v); @tick_mark_skip = v; end
+    alias :tickMarkSkip= :tick_mark_skip=
 
     # Serializes the object
     # @param [String] str
@@ -36,8 +35,8 @@ module Axlsx
     def to_xml_string(str = '')
       str << '<c:serAx>'
       super(str)
-      str << '<c:tickLblSkip val="' << @tickLblSkip.to_s << '"/>' unless @tickLblSkip.nil?
-      str << '<c:tickMarkSkip val="' << @tickMarkSkip.to_s << '"/>' unless @tickMarkSkip.nil?
+      str << '<c:tickLblSkip val="' << @tick_lbl_skip.to_s << '"/>' unless @tick_lbl_skip.nil?
+      str << '<c:tickMarkSkip val="' << @tick_mark_skip.to_s << '"/>' unless @tick_mark_skip.nil?
       str << '</c:serAx>'
     end
   end
diff --git a/lib/axlsx/drawing/val_axis.rb b/lib/axlsx/drawing/val_axis.rb
index 6e55c8ea..0e7a0800 100644
--- a/lib/axlsx/drawing/val_axis.rb
+++ b/lib/axlsx/drawing/val_axis.rb
@@ -6,21 +6,22 @@ module Axlsx
     # This element specifies how the value axis crosses the category axis.
     # must be one of [:between, :midCat]
     # @return [Symbol]
-    attr_reader :crossBetween
+    attr_reader :cross_between
+    alias :crossBetween :cross_between
 
     # Creates a new ValAxis object
-    # @param [Integer] axId the id of this axis
-    # @param [Integer] crossAx the id of the perpendicular axis
-    # @option options [Symbol] axPos
-    # @option options [Symbol] tickLblPos
-    # @option options [Symbol] crosses
-    # @option options [Symbol] crossesBetween
-    def initialize(axId, crossAx, options={})
-      self.crossBetween = :between
-      super(axId, crossAx, options)
+    # @option options [Symbol] crosses_between
+    def initialize(options={})
+      self.cross_between = :between
+      super(options)
     end
-    # @see crossBetween
-    def crossBetween=(v) RestrictionValidator.validate "ValAxis.crossBetween", [:between, :midCat], v; @crossBetween = v; end
+
+    # @see cross_between
+    def cross_between=(v)
+      RestrictionValidator.validate "ValAxis.cross_between", [:between, :midCat], v
+      @cross_between = v
+    end
+    alias :crossBetween= :cross_between=
 
     # Serializes the object
     # @param [String] str
@@ -28,7 +29,7 @@ module Axlsx
     def to_xml_string(str = '')
       str << '<c:valAx>'
       super(str)
-      str << '<c:crossBetween val="' << @crossBetween.to_s << '"/>'
+      str << '<c:crossBetween val="' << @cross_between.to_s << '"/>'
       str << '</c:valAx>'
     end