Resolves Added lambda2 and q-crit documentation to the GUI manual.
@@ -1784,13 +1784,21 @@ isnan Function: ``isnan()`` : ``isnan(expr0)``
.. _Q_Criterion_Expression_Function:
-q criterion Function: ``q_criterion()`` : ``q_criterion(expr0)``
- No description available.
+q criterion Function: ``q_criterion()`` : ``q_criterion(<gradient(velocity[0])>, <gradient(velocity[1])>, <gradient(velocity[2])>)``
+ Generates the Q-criterion value developed by Hunt et. al.. It is based on the
+ observation that, in regions where the Q-criterion is greater than zero, rotation
+ exceeds strain and, in conjunction with a pressure min, indicates the presence of
+ a vortex. The three arguments to the function are gradient vectors of the x-, y-,
+ and z-velocity. The gradient function (see :ref:`gradient() <Gradient_Expression_Function>`) can be used to create the gradient vectors.
.. _Lambda2_Expression_Function:
-lambda2 Function: ``lambda2()`` : ``lambda2(expr0)``
- No description available.
+lambda2 Function: ``lambda2()`` : ``lambda2(<gradient(velocity[0])>, <gradient(velocity[1])>, <gradient(velocity[2])>)``
+ Generates the Lambda-2 criterion. It is based on the observation that, in
+ regions where Lambda-2 is less than zero, rotation exceeds strain and, in
+ conjunction with a pressure min, indicates the presence of a vortex. The three
+ arguments to the function are gradient vectors of the x-, y-, and z-velocity.
+ The gradient function (see :ref:`gradient() <Gradient_Expression_Function>`) can be used to create the gradient vectors.
.. _Mean_Curvature_Expression_Function:
