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Equation Set Editor

Insert > Equation Set (Part Level)

Operational Sequence

1. Enter a variable name in the input field provided.
2. Build an expression in the input field provided. You can use the Get Dimension or Get Variable buttons as described below to add dimensions or variables to the expression.
3. After the expression is defined, press the Submit button. The values currently expressed in the Name, Expression, Min, and Max input fields are appended to the end of the scrolling list of equations or replaces any existing equation with the same variable name.
   
   The format used to display the definition of an equation in the list is:
   
   name = value {expression} [min, max]
   
   If an expression hasn’t been evaluated yet, its result is shown as an underscored blank space. The Apply button logs changes to the Equation Set to the database and updates the values.
   
   
4. Repeat steps 1, 2, and 3 as desired to build an equation set.
5. Pick OK to save the equation set or pick Apply, Reset, or Cancel as desired (see Other Options below).

Equation Input

• Name
  Enter the variable name for the equation or pick Get Dimension and select a dimension or pick Get Variable and select a variable from the Variable Browser.
  
  The name of the dimension or variable will appear in the input field and will be used as the variable name.
  
  
• Min/Max
  Enter the Minimum/Maximum value for the variable. An error message is displayed if a variable exceeds its limits. No change to its value is made.
  
  
• Is distance
  Check this box if the variable as a distance. When a variable is flagged as a distance, the variable value is converted to the active units when it is displayed. The expressions that define a variable are still interpreted as millimeters and degrees unless alternate units are explicitly declared (e.g., 5.in).
  
  
• Expression
  Build the expression for the equation in the text input field provided (e.g., eq1-10 or (v1+2)/v2). You can use existing dimensions and variables within the expression. Pick Get Dimension and select a dimension or pick Get Variable and select a variable from the Variable Browser. See also Using If, Then, Else Operators in Expressions
  
  
• Get Dimension
  Select a dimension from the active part or press and hold the F7 key to select a dimension external to the active part.
  
  The dimension name will be appended to either the Variable Name or Expression input field depending on which one is currently active. The name of the root object that the dimension belongs to is automatically appended to the dimension name. Refer to Variable Naming Conventions for more information.
  
  
• Get Variable
  Select a variable from the Variable Browser. The variable name will be appended to either the Name or Expression input field depending on which one is currently active. If the variable belongs to a root object other than the active root object, the name of the root object that the variable belongs to is automatically appended to the variable name. Refer to Variable Naming Conventions for more information.

Displaying Dimension Names instead of Values
You can temporarily toggle the display format of all dimensions using the Toggle Dimension Names command ( View > Dimension Names).  This allows you to better choose what dimensions to use in your equations.  Use the same command to toggle the dimensions back to their values.

 

 

Equation Options

•  Edit
  The values for the selected equation will be displayed in the input fields. Edit the equation values and pick Submit update the equation in the set.
  
  
  
• Delete
  Deletes the selected equations in the list.
  
  
  
• Move Up, Move Down
  
  
  These move the actively selected equations up or down in the equation list. This is useful for re-ordering equations that are solved sequentially.
  
  
• Pick All
  Select all equations in the set.
  
  
  
• Unpick All
  Unselect all equations that are currently selected.
  
  
  
• Unpick Last
  Unselect the last equation selected.
  
  
  
• Import
  Use this option to import variables or equations from a file. This supports the "family-of-parts" concept by allowing equation sets to be externally driven by a tabulated list of variables and their values or by equations. See Importing and Exporting Equations for a more complete discussion of this topic.
  
  
• Export
  Enter a path and file name to export the equation set to or pick the folder icon to use the File Browser. Picking the Export button will then export the equation set to the file in ASCII format. See Importing and Exporting Equations for a more complete discussion of this topic.
  
  
• Solution method
  Sets the method for solving the equation set. Select from the following:
  
  Sequential - Equations are solved sequentially (linear).
  Simultaneous - Equations are solved simultaneously (non-linear). This is
  the default method.
  
  
• Submit Equation Input
  Submits modifications in the equation edit area to the main equation list at the top of the Equation Set Editor. If the equation doesn’t already exist in the list, it is added Before or After the actively-highlighted equation based on the setting of the Before/After toggle (see below).
  
  
• Before, After Active Item
  Insert the currently defined equation before or after the selected equation. Build the new equation in the input fields, then select this button to Add the equation to the list.
  
  
• Clear Equation Input
  Removes all data entered in the Equation Input section of the Equation Editor.

Other Options

• OK - Saves the equation set and closes the Editor.
• Apply - Logs changes to the Equation Set to the database and updates the values in the list.
• Reset - Restores the equation set as it was previously saved.
• Cancel - Closes the Editor without saving the equation set.

Importing and Exporting Equations

ASCII File Format for Variable Values

Comments may be included in the file. They are lines preceded by a pound (#) sign. The first non-commented (#) row should be a list of comma-delimited or (tab-delimited) variable names preceded by a configuration label.

ASCII File Format for Equations

Variable_Name=result {expression} [min,max]

"result" should be followed by a units abbreviation (e.g. mm) if the variable is a distance. If the value of "result" is not known, enter it as zero. Once the equations are loaded, the Solve button can be used to calculate the variable values (i.e. results).

The equation format should be followed exactly, including the inclusion or exclusion of blank spaces. The only exception is the format of "expression", which is not sensitive to the inclusion of extraneous blank spaces.

Operational Sequence (Importing Equations)

1. Pick the Import button from the Equation Set Editor.
   
2. Enter the path and file name of the file to import or export in the text field provided or pick the folder icon to select a file using the File Browser.
   
3. Pick the Import button and select a file using the File Browser. If the file contain variable values (see example above), it is opened and loaded into the Import Variable Data Form shown below (go to step 3). If the file contains equations (see example above), it is imported directly into the equation list and you are given the opportunity to overwrite any values if the equations currently exist in the list.
   
4. Select a row of data from the form and pick OK. The highlighted row of data is parsed and used to update the active Equation Set.
   

The new variables/values imported into the Equation Set are not applied to the database until the OK or Apply buttons are pressed. Before the new data is applied to the database, the original data can be recovered with the Reset button. Once the data is applied to the database, the previous set of equations may be recovered using the Undo command.

Operational Sequence (Exporting Equations)

• Pick the Export button and enter a file name to export to using File Browser. The file extension is optional (e.g., equation.txt). The file will be exported to the file in ASCII format (refer to the example above).

1. Equations, Expressions and Variables
2. Using Embedded Text Variables
3. Create/Edit Local Variable (3D/2D)
4. Variable Browser
5. Referencing Variables from Parts Associated with Drawing Sheets
6. Edit Part Equations
7. Insert Sketch Equations
8. Valid Expression Functions
9. General Notes for Equations and Expressions
10. Editing Command Line Expressions
11. Using Units within Expressions
12. Using If, Then, Else Operators in Expressions
13. Insert Part Equations
14. Variable Naming Conventions
15. Variable Names and Sketch Dimensions
16. Using Command Line Expressions