Allow python functions to override catgeories.

Also adds simple Python Jacobian test.
Refs #970

Code/Mantid/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunctionAdapter.h

@@ -45,6 +45,8 @@ namespace Mantid
 
       /// Returns the name of the function
       std::string name() const;
+      /// Specify a category for the function
+      const std::string category() const;
       /// Declare all attributes & parameters
       void init();
 

Code/Mantid/Framework/PythonInterface/mantid/api/src/Exports/IFunction.cpp

@@ -52,6 +52,8 @@ void export_IFunction()
   class_<IFunction, IFunctionAdapter, boost::noncopyable>("IFunction", "Base class for all functions", no_init)
     .def("name", &IFunction::name, "Return the name of the function")
 
+    .def("category", &IFunctionAdapter::category, "Return a semi-colon(;) separated string for the categories this class should belong to. For sub-categories use a \\ separator")
+
     .def("initialize", &IFunction::initialize, "Declares any parameters and attributes on the function")
 
     .def("getCategories", &getCategories, "Returns a list of the categories for an algorithm")

Code/Mantid/Framework/PythonInterface/mantid/api/src/FitFunctions/IFunctionAdapter.cpp

@@ -29,6 +29,14 @@ namespace Mantid
       return m_name;
     }
 
+    /**
+     * Specify a category for the function
+     */
+    const std::string IFunctionAdapter::category() const
+    {
+      return CallMethod0<std::string>::dispatchWithDefaultReturn(getSelf(),"category", IFunction::category());
+    }
+
     /**
      */
     void IFunctionAdapter::init()

Code/Mantid/Framework/PythonInterface/test/python/mantid/api/CMakeLists.txt

@@ -18,6 +18,7 @@ set ( TEST_PY_FILES
   IFunction1DTest.py
   IPeaksWorkspaceTest.py
   ITableWorkspaceTest.py
+  JacobianTest.py
   MatrixWorkspaceTest.py
   MDHistoWorkspaceTest.py
   MultipleExperimentInfos.py

Code/Mantid/Framework/PythonInterface/test/python/mantid/api/IFunction1DTest.py

@@ -2,8 +2,16 @@
 from mantid.api import IFunction1D, IFunction, FunctionFactory
 import numpy as np
 
+class NoCatgeoryFunction(IFunction1D):
+
+    def init(self):
+        pass
+
 class Times2(IFunction1D):
 
+    def category(self):
+        return "SimpleFunction"
+
     def init(self):
         self.declareAttribute("IntAtt", 1)
         self.declareAttribute("DoubleAtt", 3.4)
@@ -30,6 +38,18 @@ def test_instance_can_be_created_from_factory(self):
         self.assertTrue(isinstance(func, IFunction1D))
         FunctionFactory.unsubscribe(func_name)
 
+    def test_category_with_no_override_returns_default_category(self):
+        FunctionFactory.subscribe(NoCatgeoryFunction)
+        func = FunctionFactory.createFunction("NoCatgeoryFunction")
+        self.assertEquals("General", func.category())
+        FunctionFactory.unsubscribe("NoCatgeoryFunction")
+
+    def test_category_override_returns_overridden_result(self):
+        FunctionFactory.subscribe(Times2)
+        func = FunctionFactory.createFunction("Times2")
+        self.assertEquals("SimpleFunction", func.category())
+        FunctionFactory.unsubscribe("Times2")
+
     def test_declareAttribute_only_accepts_known_types(self):
         func = Times2()
         func.initialize() # Contains known types