Input parameters

Here we focus on input parameters. They are displayed in a list giving all the properties that define the input parameters, as shown in the figure below.

Figure 55: List of input parameters

Adding input parameters

Input parameters from submodel

Input parameters from global parameter

Input parameters user defined

Adding an input parameter means that you will be able to specify its value using an ASCII file at run time.

Input parameters may be of different origins:

• submodel parameters,

• global parameters,

• user-defined (meaning they have no link at all with the Simcenter Amesim model).

The way of adding an input depends on its origin. In all cases do the following first.

Procedure

1. Ensure you are in Parameter mode.

2. Use Configure > Study parameters or click the Study parameters button from the mode contextual toolbar to open the Study Manager.

3. Add parameters to the selection of inputs:

To add...

Proceed as follows...

Submodel parameters

Double-click the component that holds the parameter you are interested in to open its Change Parameters dialog box.

Select the parameter you are interested in, drag it and drop it on the Input parameters table of the Parameters tab.

Global parameters

Open the Global Parameters Setup dialog box from the Configure menu.

Select the global parameter you are interested in, drag it and drop it on the Input parameters table of the Parameters tab.

User defined inputs

Right-click the Input parameters table of the Parameters tab.

Select Add.

This user defined input is mainly used for formatted string. The concept of formatted string is explained in Formatted string input parameters.

A new line appears in the input list.

4. Modify the names and parameter properties as explained in Input parameter properties.

Results

You can also add submodel parameters and global parameters directly from the Studies tab, into the Inputs/Controls list of your active study. These parameters will then be available to all studies.

Note

The drag and dropped parameter is selected in the input list of the current active study only.

Creating groups of input parameters

You can organize input parameters within groups. You must create the group first, then create or add input parameters in that group. You can create sub-groups in your groups of input parameters, and further sub-groups inside those sub-groups to any depth, as you require.

To create a new group:

Procedure

1. Right-click on the Input parameters table and select New Group.

The new group appears in the list.

2. Rename it as you require.

3. Add input parameters as described in Adding input parameters.

Note You cannot drag and drop already existing input parameters into the newly created group.

You can also drag and drop groups of global parameters directly into the Input parameters table or the Inputs/Controls list of a study.

Removing input parameters

Input parameters removing

You can remove input parameters from the Parameters tab only. To remove a parameter from Input parameters:

• right-click on it and select Remove, or,

• select it in the list and press the Del key.

Input parameter properties

Once the input parameters have been added, their properties have to be set. The following paragraphs details the properties that define an input parameter.

• NameThe name is the identifier of the parameter. Thus, it has to be unique (a name used for an input cannot be used for another input or output). In the whole Study Manager module, this name is used to refer to that input parameter.This name has to start with an alphabetical character and must contain only alphanumerical characters and underscores.For convenience, a default name is automatically set by Simcenter Amesim. It is strongly advised that you set it to a name which is meaningful to you.

• Type of parameters Input parameters types Input parameters may be of 6 types. For a user defined input, when created, it will be of type Real but it can be set to any of the 6 types. For other input variables, only a subset of the types is available. For submodel real parameters or global real parameters the type when created is Real but it can be set to Real or Discrete real. For submodel integer parameters or global integer parameters the type when created is Integer but it can be set to Integer or Discrete integer. For submodel text parameters or global text parameters the type must be Formatted string or String list. For all types the Name and Default value fields must be set. In addition for each of the 6 types other fields must be set as follows:

Possible values

Upper bound

Lower bound

Real

No

Yes

Yes

Discrete real

Yes

No

No

Integer

No

Yes

Yes

Discrete integer

Yes

No

No

Formatted string

No

No

No

String list

Yes

No

No

Possible values are lists of one or more elements separated by semicolons. A semicolon after the last member of the list is optional. Here is an example of a Real list: 12;24.5;1.23e-1An example of Possible values for the String list type is a list of file names: FluidProps1.data;FluidProps2.data;FluidProps7.data

Real input parameters

Integer input parameters

Real and Integer: The parameter can take any value between an Upper bound and Lower bound.

Discrete real input parameters

Discrete integer input parameters

Real discrete and Integer discrete: The value of the parameter can take any of the values that are declared as being Possible values. The Default value must be a possible value.

String list input parameters

String list: The value of the parameter can only be chosen among the values that are declared as being Possible values. During the execution stage, you will not directly set its value but assign to it the index of the desired string in the possible string list.

Formatted string: This is a string that will replace some formatted elements with current values of other parameters. Thus, at the execution stage, you do not set its value directly as it is done automatically using other parameter values. The Formatted string is more complex than the other types and hence there is a special section devoted to it: Formatted string Input Parameters.

Checks are preformed when you try to save. If an error is detected, a suitable message is displayed.Figure 56: Examples of errors in the input parameters.

Note Discrete parameters are only useful if you intend to use direct interfaces provided in Simcenter Amesim or Simcenter Amesim design exploration build-in features. In other cases, it is not used by the Study Manager and may be filled in by the user just for information purposes.

• Read-only fieldsWhen an input parameter is a submodel parameter or a global parameter, certain information is inherited which becomes read-only fields of the input parameter. If the source is a submodel parameter the Submodel field is constructed from the submodel name and instance number. The parameter title is used for the Simcenter Amesim Title field. If it is a real parameter, its unit is copied to the Units field.Figure 57: Input parameter for a submodel parameter

For global parameters the treatment is similar.Figure 58: Input for a global parameter

For user defined input parameters, the Submodel, Simcenter Amesim Title and Units fields are empty.Figure 59: Input for a user defined parameter

Vectors as input parameters

vectors as input parameters

Input parameters with vectors

Some submodel parameters are vectors. In this case, some of the behavior depends on the expand option you have selected. If you drag and drop a vector quantity in the Input parameters table:

• if the Expand vectors option is enabled, the individual elements of the vector are displayed,

• if the Expand vectors option is disabled, the vector is displayed as a single quantity.

It is important to note you cannot have a single element of the vector only. It is all or nothing! Other important points to note for vectors are that regardless of the Expand vectors state:

• Change the Name field in the normal way but do not add any sort of bracket (this will be done automatically when you validate). All element names will be updated.

• Remove the vector in the normal way (right-click and select Remove or press the Delete key). All vector elements will be removed.

For other fields the behavior is consistent with the Change Parameters dialog box, the contextual Parameters window, or the Watch parameters window.

With Expand vectors enabled, you can change individual elements.

If the individual elements are set to different values, a ??? will be displayed when Expand vectors is disabled.

If you set a value with Expand vectors displayed, the value will be set for every value of the array.

Formatted string input parameters

Formatted string input parameters

The input parameter type Formatted string is more complex that the other types and deserve a special section. A simple example is given first after which there is a general description.

Figure 60: Simple use of a Formatted string.

The Formatted string is used to define a submodel text parameter. In this case it is actually the name of a data file. The part of the string specified by ${FluidIndex} is an instruction to insert into the string the current value of the input parameter named FluidIndex. If FluidIndex has the value 8, you will get the string fluid8.data. Since FluidIndex can take any values between 0 and 12 inclusive there are 13 distinct strings that can be defined.

Now we will give a general description.

The Formatted string is a way for you to make a text parameter evolve according to the value of other parameters. It uses formatted elements which will be replaced at run time. These formatted elements are made of the name of an integer or real input parameter associated with "${}" characters. They look like ${parameter_name}.

At run time, every occurrence of ${parameter_name} will be replaced by the current value of the parameter named parameter_name.

Note

If you want an input parameter to be the expression of other input parameters, you can define the expression as global parameters. When you create a study parameter in the Study Manager, you must define the individual parameters before the parameters which are based on the formula.