Conditions that Make Your Design Work the Way You Want
Conditional formula
For each 3D and 2D parametric design, conditions exist where variables need to have a specific value.
Classic example: As a part gets longer; holes need to be added to maintain a safe distance between them.
Logic arguments
Basic principle consists of verifying a condition with the help of arguments. Logic arguments used
by Solid Edge:
• Lesser than <
• Equal =
• Greater than >
Once a condition is verified, Solid Edge returns a value showing if the condition is valid (true) or
non-valid (false).
• For a valid condition (true), the returned value is -1
• For a non valid condition (false), the returned value is 0
Note:
The arguments can be combined: Equal or Greater than ( => )
Isolate arguments
Each time we need to verify a condition, isolate it between parenthesis
• = (Width = Length)
• = (Width < Length)
Example of a conditional syntax:
| Length | Width | Depth |
| 3.000 | 3.000 | (Length = Width) |
= (Length = Width) ⇒ Valid condition (-1) ⇒ Return value for the Depth is -1
Absolute value
To ensure a positive value is returned, the use of the mathematical argument ABS can be used.
=ABS (Length = Width) ⇒Valid condition ABS (-1) ⇒ Return value for the Depth is 1
A multiplier argument can also be use:
= -1*(Length = Width) ⇒ Valid condition -1*(-1) ⇒ Return value for the Depth is 1
From this simple example, it is easy to understand that we need to multiply the return value by the desired
quantity.
Based on this:
= -3*(Length = Width) ⇒ Valid condition -3*(-1) ⇒ Return value is 3
=ABS (3*(Length = Width)) ⇒ Valid condition ABS(3*(-1)) ⇒ Return value is 3
Logic operators
When more than one condition needs to be validated, it is necessary to use the operators «AND»
… «OR». Notice arguments have been combined to indicate we need to check the length to be
«equal or larger then»
=ABS (3*(Length => 6) and (Length < 12))
= -3*(Length => 6) and (Length < 12))
Note:
1. Operator * and + can be use to replace AND…OR, but I recommend keeping those for mathematic
operations. This should help make the writing and reading easier.
2. It may be more practical to use a control value(s) to help the writing and the reading of the formula.
http://soliddna.wordpress.com/synchronous_technology/sewst-interface/variables-table/
=ABS (3*(Length => Value_min) and (Length < Value_max ))
In order to help you manipulate and build conditional formulas, I break the process into
four steps. Following these steps will help you in the writing of a complex formula.
These steps can also be use has a tutorial.
Step 1 – Identify the conditions
Step 2 – Write the condition
Step 3 – Add necessary logic operators
Step 4 – Wrap everything into a single formula
Conditional formula
| Step 1 2 holes ⇒ 0 – 6 inch 3 holes ⇒ 6 – 12 inch 4 holes ⇒ 12 + |
| Step 2 2*(Length <= 6) 3*(Length > 6) 4*(Length > 12) 3*(Length <= 12) |
| Step 3 2*(Length <= 6) or 3*(Length > 6) and 3*(Length <= 12) or 4*(Length > 12) |
| Step 4 =ABS((2*(Length <= 6)) or (3*(Length > 6) and (Length <= 12)) or (4*(Length > 12))) |
