[gnumeric] xlsx: import regression equations too.

[Morten Welinder <mortenw src gnome org>]

commit dce203d65a981a2ff70f71ce9f3ee6b48735ae5d
Author: Morten Welinder <terra gnome org>
Date:   Tue Jan 20 13:05:57 2015 -0500

    xlsx: import regression equations too.

 NEWS                              |    2 +-
 plugins/excel/xlsx-read-drawing.c |   43 +++++++++++++++++++++++++++++++++++-
 2 files changed, 42 insertions(+), 3 deletions(-)
---
diff --git a/NEWS b/NEWS
index df84ce0..0588942 100644
--- a/NEWS
+++ b/NEWS
@@ -26,7 +26,7 @@ Morten:
        * Fix sheet-filter problem with errors.  [#742601]
        * Improve error handling for .gnumeric a bit.
        * Improve xlsx graph import: line colour; marker size; marker color;
-         no lines; bounding box; trend lines.
+         no lines; bounding box; trend lines; regression equations.
        * Improve xlsx graph export: line style; bar/col direction; marker shape;
          marker size; marker color; axis label; chart title.
        * Improve xlsx export: default col widths; schema validity.
diff --git a/plugins/excel/xlsx-read-drawing.c b/plugins/excel/xlsx-read-drawing.c
index bd108dc..dcd1f58 100644
--- a/plugins/excel/xlsx-read-drawing.c
+++ b/plugins/excel/xlsx-read-drawing.c
@@ -939,6 +939,45 @@ xlsx_ser_trendline_type (GsfXMLIn *xin, G_GNUC_UNUSED  xmlChar const **attrs)
        }
 }
 
+static GogObject *
+xlsx_get_trend_eq (XLSXReadState *state)
+{
+       const char *role = "Equation";
+       GogObject *eq = gog_object_get_child_by_name (state->cur_obj, role);
+
+       if (!eq) {
+               eq = gog_object_add_by_name (state->cur_obj, role, NULL);
+               g_object_set (eq, "show-r2", FALSE, "show-eq", FALSE, NULL);
+       }
+
+       return eq;
+}      
+
+
+static void
+xlsx_ser_trendline_disprsqr (GsfXMLIn *xin, G_GNUC_UNUSED  xmlChar const **attrs)
+{
+       XLSXReadState *state = (XLSXReadState *)xin->user_state;
+       gboolean disp;
+
+       if (simple_bool (xin, attrs, &disp) && disp) {
+               GogObject *eq = xlsx_get_trend_eq (state);
+               g_object_set (eq, "show-r2", TRUE, NULL);
+       }
+}
+
+static void
+xlsx_ser_trendline_dispeq (GsfXMLIn *xin, G_GNUC_UNUSED  xmlChar const **attrs)
+{
+       XLSXReadState *state = (XLSXReadState *)xin->user_state;
+       gboolean disp;
+
+       if (simple_bool (xin, attrs, &disp) && disp) {
+               GogObject *eq = xlsx_get_trend_eq (state);
+               g_object_set (eq, "show-eq", TRUE, NULL);
+       }
+}
+
 
 static void
 xlsx_ser_labels_show_val (GsfXMLIn *xin, xmlChar const **attrs)
@@ -1916,8 +1955,8 @@ GSF_XML_IN_NODE_FULL (START, CHART_SPACE, XL_NS_CHART, "chartSpace", GSF_XML_NO_
         GSF_XML_IN_NODE (SCATTER, SERIES, XL_NS_CHART, "ser", GSF_XML_NO_CONTENT, &xlsx_chart_ser_start, 
&xlsx_chart_ser_end),
           GSF_XML_IN_NODE (SERIES, SERIES_TRENDLINE, XL_NS_CHART,      "trendline", GSF_XML_NO_CONTENT, 
&xlsx_ser_trendline_start, &xlsx_ser_trendline_end),
             GSF_XML_IN_NODE (SERIES_TRENDLINE, SERIES_TRENDLINE_TYPE, XL_NS_CHART,     "trendlineType", 
GSF_XML_NO_CONTENT, &xlsx_ser_trendline_type, NULL),
-            GSF_XML_IN_NODE (SERIES_TRENDLINE, SERIES_TRENDLINE_RSQR, XL_NS_CHART,     "dispRSqr", 
GSF_XML_NO_CONTENT, NULL, NULL),
-            GSF_XML_IN_NODE (SERIES_TRENDLINE, SERIES_TRENDLINE_EQ, XL_NS_CHART,       "dispEq", 
GSF_XML_NO_CONTENT, NULL, NULL),
+            GSF_XML_IN_NODE (SERIES_TRENDLINE, SERIES_TRENDLINE_RSQR, XL_NS_CHART,     "dispRSqr", 
GSF_XML_NO_CONTENT, &xlsx_ser_trendline_disprsqr, NULL),
+            GSF_XML_IN_NODE (SERIES_TRENDLINE, SERIES_TRENDLINE_EQ, XL_NS_CHART,       "dispEq", 
GSF_XML_NO_CONTENT, &xlsx_ser_trendline_dispeq, NULL),
             GSF_XML_IN_NODE (SERIES_TRENDLINE, SERIES_TRENDLINE_LABEL, XL_NS_CHART,    "trendlineLbl", 
GSF_XML_NO_CONTENT, NULL, NULL),
               GSF_XML_IN_NODE (SERIES_TRENDLINE_LABEL, SERIES_TRENDLINE_LABEL_LAYOUT, XL_NS_CHART, "layout", 
GSF_XML_NO_CONTENT, NULL, NULL),
               GSF_XML_IN_NODE (SERIES_TRENDLINE_LABEL_LAYOUT, SERIES_TRENDLINE_LABEL_LAYOUT_MANUAL, 
XL_NS_CHART, "manualLayout", GSF_XML_NO_CONTENT, NULL, NULL),