Studies and Study Steps

In the COMSOL Desktop, you create one or more studies, each with one or more study steps to compute the solution to a model. The studies generate a solver sequence with the solvers and other solver features that correspond to the study steps in the study.


	Study and Study Step Types in the COMSOL Multiphysics Reference Manual.

Creating a Study and Adding Study Step

The following commands create a study std1 and adds a Stationary study step to that study:

model.study().create("std1");

model.study("std1").create("stat", "Stationary");

Running (Computing) a Study

To run a study, use

model.study(<tag>).run();

The run() command corresponds to clicking on a node in the COMSOL Desktop.

Creating a Reference to a Study Step

You can also create a reference to an existing study step from a solver sequence:

model.sol("sol1").create("st1", "StudyStep");

model.sol("sol1").feature("st1").set("study", "std1");

model.sol("sol1").feature("st1").set("studystep", "stat");

Attaching a Study

It is also possible to attach a study for making a solver sequence or batch feature part of the study sequence:

model.sol("sol1").attach("std1");

The attach() operation implies calling study(<tag>)(see below). You can only have one solver sequence attached to each study but you can have multiple batch features.

Associating a Solver Sequence With a Study

You can associate a solver sequence with a study using the following syntax:

model.sol("sol1").study("std1");

In contrast, attach() (see above) also makes the solver sequence part of the study sequence.

Main Study Feature Settings

Table 6-83: Methods for the Main Study Feature Settings
Method	Description
isGenConv()	True if convergence plots should be generated.
isGenIntermediatePlots()	True if plots for intermediate Stored Solution nodes should be generated.
isGenPlots()	True if default results plots should be generated.
isPlotUndefVals()	True if plots should be generated showing locations of undefined values.
isStoreSolution()	True if a Store Solution node should be generated for each intermediate study step.
setGenConv(boolean)	Set to true if convergence plots should be generated.
setGenIntermediatePlots(boolean)	Set to true to generate plots for intermediate Store Solution nodes.
setGenPlots(boolean)	Set to true if default results plots should be generated.
setPlotUndefVals(boolean)	Set to true to generate plots showing the location of undefined values.
setStoreSolution(boolean)	Set to true to generate a Store Solution node for each intermediate study step.

For example, use

model.study("std1").setGenConv(true);

to generate convergence plots when computing the solution.

Common Study Step Properties

The following table explains properties available for all study steps defining equations:

Table 6-84: Physics and Variables Selection

Choose physics interfaces and other features to solve for. Allowed keys are

•

A physics interface tag

•

frame: followed by a Frame entity tag

•

rom: followed by a ReducedModel entity tag

•

A component tag followed by :shape controlling shape optimization in the component

•

A component tag followed by :topopt controlling topology optimization in the component

Allowed values are on or off. Default depends on the key.

activateCoupling

String Map

Choose coupling features to solve for. Allowed keys are MultiphysicsCoupling entity tags. Allowed values are on or off. Default is on.

activaterom

String Map

Choose reduced-order model output variables to solve for. Allowed keys are ReducedModel entity tags. Allowed values are on or off. Default is off.

disabledcommon

Reference Array

CommonFeature entities disabled when useadvanceddisable is on. Not all types can be disabled.

disabledcoordinatesystems

Reference Array

Coordinate system features disabled when useadvanceddisable is on. Only types representing PMLs, infinite elements and absorbing layers can be disabled.

disabledcoupling

Reference Array

MultiphysicsCoupling entities disabled when useadvanceddisable is on.

disabledpair

Reference Array

Pair entities disabled useadvanceddisable is on.

disabledphysics

Reference Array

Physics interfaces and features disabled when useadvanceddisable is on. Allowed reference tags are:

•

A physics interface tag

•

A path to a physics feature of the form phys_tag/feature_tag/...

disabledreduced

Reference Array

Reduced-order model features disabled when useadvanceddisable is on.

disabledvariables

Reference Array

Variables entities disabled when useadvanceddisable is on.

disableFrameControl

Reference Array

Entities which should not control any frame when useadvanceddisable is on. Allowed reference tags are:

•

A physics interface tag

•

frame: followed by a Frame entity tag

•

A component tag followed by :shape controlling shape optimization in the component

discretization

String Map

Select discretization for physics interfaces. Allowed keys are the same as in activate. Allowed values are physics (also default) and tags of any Discretization feature belonging to the key entity.

equationform

String Map

Override study step equation form for physics interfaces. Allowed keys are the same as in activate. Allowed values are physics (also default if the physics allows setting equation form) and any equation form allowed by the physics interface settings.

equationform_freq

String Map

Specify frequency to use for a physics interface when its equation form is set to a frequency-domain type using the equationform property. Allowed keys are the same as in activate. Allowed values are parameter expressions. The default is the same as the default in the physics interface settings.

equationform_freq_src

String Map

Specify whether an equation-based physics interface should define time derivatives using the main frequency of a frequency-domain study step or a specific frequency given in equationform_freq. Allowed values are fromSolver (the default) and userdef.

reconstructors

String Map

Choose a reduced-order model to reconstruct dependent variables in a physics interface not solved for. Allowed keys are tags of physics interfaces not solved for and for which there exists at least one reconstructing reduced-order model. Allowed values are none (also default) and tags of ReducedModel entities capable of reconstructing the key interface’s dependent variables.

useadvanceddisable

on | off

off

Enable advanced frame control and disabling of model entities.

Properties Of Specific Study Step Types

The following table lists the major study steps with links to documentation of available properties for each study step: