--- a/svghmi/analyse_widget.xslt	Wed Jun 01 09:14:19 2022 +0200
+++ b/svghmi/analyse_widget.xslt	Wed Jun 01 09:15:26 2022 +0200
@@ -2,7 +2,7 @@
 <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:exsl="http://exslt.org/common" xmlns:regexp="http://exslt.org/regular-expressions" xmlns:str="http://exslt.org/strings" xmlns:func="http://exslt.org/functions" xmlns:svg="http://www.w3.org/2000/svg" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" version="1.0" extension-element-prefixes="ns func exsl regexp str dyn" exclude-result-prefixes="ns func exsl regexp str dyn svg inkscape">
   <xsl:output method="xml"/>
   <xsl:variable name="indexed_hmitree" select="/.."/>
-  <xsl:variable name="pathregex" select="'^([^\[,]+)(\[[^\]]+\])?([\d,]*)$'"/>
+  <xsl:variable name="pathregex" select="'^([^\[,]+)(\[[^\]]+\])?([-.\d,]*)$'"/>
   <xsl:template mode="parselabel" match="*">
     <xsl:variable name="label" select="@inkscape:label"/>
     <xsl:variable name="id" select="@id"/>
@@ -50,6 +50,16 @@
           <xsl:value-of select="$type"/>
         </xsl:attribute>
         <xsl:if test="$freq">
+          <xsl:if test="not(regexp:test($freq,'^[0-9]*(\.[0-9]+)?[smh]?'))">
+            <xsl:message terminate="yes">
+              <xsl:text>Widget id:</xsl:text>
+              <xsl:value-of select="$id"/>
+              <xsl:text> label:</xsl:text>
+              <xsl:value-of select="$label"/>
+              <xsl:text> has wrong syntax of frequency forcing </xsl:text>
+              <xsl:value-of select="$freq"/>
+            </xsl:message>
+          </xsl:if>
           <xsl:attribute name="freq">
             <xsl:value-of select="$freq"/>
           </xsl:attribute>
@@ -223,8 +233,6 @@
   </xsl:template>
   <xsl:template name="generated_button_class">
     <xsl:param name="fsm"/>
-    <xsl:text>    frequency = 5;
-</xsl:text>
     <xsl:text>    display = "inactive";
 </xsl:text>
     <xsl:text>    state = "init";
@@ -717,7 +725,7 @@
       <xsl:value-of select="@type"/>
     </type>
     <longdesc>
-      <xsl:text>PathSlider - 
+      <xsl:text>PathSlider -
 </xsl:text>
     </longdesc>
     <shortdesc>
@@ -877,6 +885,62 @@
       <xsl:text>Boolean variable</xsl:text>
     </path>
   </xsl:template>
+  <xsl:template match="widget[@type='XYGraph']" mode="widget_desc">
+    <type>
+      <xsl:value-of select="@type"/>
+    </type>
+    <longdesc>
+      <xsl:text>XYGraph draws a cartesian trend graph re-using styles given for axis,
+</xsl:text>
+      <xsl:text>grid/marks, legends and curves.
+</xsl:text>
+      <xsl:text>
+</xsl:text>
+      <xsl:text>Elements labeled "x_axis" and "y_axis" are svg:groups containg:
+</xsl:text>
+      <xsl:text> - "axis_label" svg:text gives style an alignment for axis labels.
+</xsl:text>
+      <xsl:text> - "interval_major_mark" and "interval_minor_mark" are svg elements to be
+</xsl:text>
+      <xsl:text>   duplicated along axis line to form intervals marks.
+</xsl:text>
+      <xsl:text> - "axis_line"  svg:path is the axis line. Paths must be intersect and their
+</xsl:text>
+      <xsl:text>   bounding box is the chart wall.
+</xsl:text>
+      <xsl:text>
+</xsl:text>
+      <xsl:text>Elements labeled "curve_0", "curve_1", ... are paths whose styles are used
+</xsl:text>
+      <xsl:text>to draw curves corresponding to data from variables passed as HMI tree paths.
+</xsl:text>
+      <xsl:text>"curve_0" is mandatory. HMI variables outnumbering given curves are ignored.
+</xsl:text>
+      <xsl:text>
+</xsl:text>
+    </longdesc>
+    <shortdesc>
+      <xsl:text>Cartesian trend graph showing values of given variables over time</xsl:text>
+    </shortdesc>
+    <path name="value" count="1+" accepts="HMI_INT,HMI_REAL">
+      <xsl:text>value</xsl:text>
+    </path>
+    <arg name="size" accepts="int">
+      <xsl:text>buffer size</xsl:text>
+    </arg>
+    <arg name="xformat" count="optional" accepts="string">
+      <xsl:text>format string for X label</xsl:text>
+    </arg>
+    <arg name="yformat" count="optional" accepts="string">
+      <xsl:text>format string for Y label</xsl:text>
+    </arg>
+    <arg name="xmin" count="optional" accepts="int,real">
+      <xsl:text>minimum value foe X axis</xsl:text>
+    </arg>
+    <arg name="xmax" count="optional" accepts="int,real">
+      <xsl:text>maximum value for X axis</xsl:text>
+    </arg>
+  </xsl:template>
   <xsl:template mode="document" match="@* | node()">
     <xsl:copy>
       <xsl:apply-templates mode="document" select="@* | node()"/>