support for tolerance and decimals

cms/static/grammar.jspeg

@@ -10,10 +10,21 @@ start
 StudentProducedResponseIdentifier
   = '='
 
+NumericalToleranceValueType
+  = decimal / percentage / integer
+
+NumericalTolerance
+  = '+-' OptionalSpaces value:NumericalToleranceValueType OptionalSpaces
+    {
+      return value;
+    }
+
 NumericalResponse
-  = StudentProducedResponseIdentifier OptionalSpaces '(' OptionalSpaces value:NumericalValue OptionalSpaces ')' OptionalSpaces Linebreak
+  = StudentProducedResponseIdentifier OptionalSpaces '(' OptionalSpaces value:NumericalValue OptionalSpaces tolerance:NumericalTolerance? ')' OptionalSpaces Linebreak
     {
-      return {'type': 'numerical', 'answer': value};
+      if (tolerance == "")
+        tolerance = "5%"
+      return {'type': 'numerical', 'answer': value, 'tolerance': tolerance};
     }
 
 StringResponse
@@ -80,7 +91,6 @@ OptionalSpaces
 Linebreak
   = ('\n')
 
-
 NumericalValue
   = additive
 
@@ -96,10 +106,16 @@ multiplicative
   / primary
 
 primary
-  = integer
+  = decimal
+  / integer
   / "(" additive:additive ")" { return additive; }
 
+decimal "decimal"
+  = first:[0-9]+ point:'.' last:[0-9]+
+    { return parseFloat(first.join("") + point + last.join("")); }
+
 integer "integer"
   = digits:[0-9]+ { return parseInt(digits.join(""), 10); }
 
-
+percentage "percentage"
+  = digits:[0-9]+ '%' { return parseInt(digits.join(""), 10) + '%'; }
\ No newline at end of file

common/lib/xmodule/xmodule/js/src/capa/edit.coffee

@@ -81,6 +81,12 @@ class @CapaDescriptor
                 newel = $(doc.createElement('numericalresponse'))
                 newel.attr 'answer', section.answer
 
+                tolerance = $(doc.createElement('responseparam'))
+                tolerance.attr 'type', 'tolerance'
+                tolerance.attr 'default', section.tolerance
+                tolerance.attr 'name', 'tol'
+                tolerance.attr 'description', 'Numerical Tolerance'
+                newel.append tolerance
                 newel.append doc.createElement('textline') 
                 problem.append(newel)