In the Compile Equations () node’s Settings window, you specify which study and study step to use when computing the current solver configuration and compiling the equations to solve. The node displays the name of the selected study step: Compile Equations: Stationary, for example. Right-click this node and select Statistics to see the number of degrees of freedom for the solver (see The Statistics Page).

Specify the study in the Use study list and the study step in the Use study step list. By default, you get the parent study and its first study step.

Complex variables are by default represented by complex-valued degrees of freedom. By selecting the Split complex variables in real and imaginary parts checkbox, the representation of complex variables is changed to using separate real degrees of freedom for the real and imaginary parts. The split representation can improve convergence where nonanalytic functions of complex variables are used in equations. Using a split representation also makes it possible to avoid complex pollution (a small nonzero imaginary component) of real variables by specifying a real or complex value type for variables. If you use a split representation of complex variables, specify the value type of dependent variables in the Discretization sections in the Settings windows for the main physics nodes (to see this setting, click the Show More Options button () and select Advanced Physics Options in the Show More Options dialog).

You can choose a partitioning method from the Partitioning method for distributed computing list: From parent (the parent Solution node; this is the default setting), Mesh ordering, Nested dissection, Weighted nested dissection, or Off. See Cluster Computing Settings for more information.

The Linearize small mesh elements setting can be used to control the geometric shape-function order of small mesh elements used to compile the equations of the current study. This option only affects the current study and modifies the setting for the Geometry shape function in the Curved Mesh Elements section of the Settings window of the Component node when the Avoid inverted elements by curving interior domain elements option is enabled. The default option is Physics controlled, whereby the active physics interfaces may reduce the geometric order for stability or performance reasons when resolving geometric curvature below a certain length scale is not relevant. When the option Off is selected, this functionality is disabled. By specifying the User controlled option, you can enter a length expression for the maximum element size threshold per component in the table below to prevent mesh elements smaller than this threshold from being curved. Note that each entered expression has to evaluate to a length where the default unit is the length unit of the respective geometry, and the evaluation is performed in a limited global context without access to most model variables. However, the expressions can depend on model parameters.

The default behavior is that you try to solve the problem for the full geometry. However, if you prefer, you can choose to solve only on a subset of the full geometry. To do this, change Use entities from All to Selected and add named selections to the Selections list using the Add button (). The study will now compute using only the added selections, and everything outside those selections will be neglected.

Select the Keep warnings in stored log checkbox if you want to keep any warnings in the log.