Merge pull request #245 from patorash/feature-line-chart-smooth

smooth line for line chart

2 files changed, 12 insertions, 3 deletions

diff --git a/lib/axlsx/drawing/line_chart.rb b/lib/axlsx/drawing/line_chart.rb
index 8ff32412..699050dc 100644
--- a/lib/axlsx/drawing/line_chart.rb
+++ b/lib/axlsx/drawing/line_chart.rb
@@ -39,8 +39,6 @@ module Axlsx
     # @return [Symbol]
     attr_reader :grouping
 
-    attr_accessor :smooth
-
     # Creates a new line chart object
     # @param [GraphicFrame] frame The workbook that owns this chart.
     # @option options [Cell, String] title
@@ -85,7 +83,6 @@ module Axlsx
         @series.each { |ser| ser.to_xml_string(str_inner) }
         @d_lbls.to_xml_string(str_inner) if @d_lbls
         yield str_inner if block_given?
-        str_inner << '<c:smooth val="1"/>' if smooth
         axes.to_xml_string(str_inner, :ids => true)
         str_inner << "</c:" << node_name << ">"
         axes.to_xml_string(str_inner)
diff --git a/lib/axlsx/drawing/line_series.rb b/lib/axlsx/drawing/line_series.rb
index b011e0b6..93478b8f 100644
--- a/lib/axlsx/drawing/line_series.rb
+++ b/lib/axlsx/drawing/line_series.rb
@@ -23,12 +23,17 @@ module Axlsx
     # @return [Boolean]
     attr_reader :show_marker
 
+    # line smoothing on values
+    # @return [Boolean]
+    attr_reader :smooth
+
     # Creates a new series
     # @option options [Array, SimpleTypedList] data
     # @option options [Array, SimpleTypedList] labels
     # @param [Chart] chart
     def initialize(chart, options={})
       @show_marker = false
+      @smooth = false
       @labels, @data = nil, nil
       super(chart, options)
       @labels = AxDataSource.new(:data => options[:labels]) unless options[:labels].nil?
@@ -46,6 +51,12 @@ module Axlsx
       @show_marker = v
     end
 
+    # @see smooth
+    def smooth=(v)
+      Axlsx::validate_boolean(v)
+      @smooth = v
+    end
+
     # Serializes the object
     # @param [String] str
     # @return [String]
@@ -66,6 +77,7 @@ module Axlsx
         str << '<c:marker><c:symbol val="none"/></c:marker>' unless @show_marker
         @labels.to_xml_string(str) unless @labels.nil?
         @data.to_xml_string(str) unless @data.nil?
+        str << '<c:smooth val="' << ((smooth) ? '1' : '0') << '"/>'
       end
     end