Conditional formula

For each 3D and 2D parametric design, conditions exist where variables need to have a specific value.
Classic example: Has a part get longer; holes need to be add to maintain a safe distance between them.

Logic arguments

Basic principle consists of verifying a condition with the help of arguments. Logic arguments use by Solid Edge:

• Smaller then <
• Equal =
• Larger then >

Once a condition is verify, Solid Edge return a value showing if the condition is valid (true) or non-valid (false).

• For a valid condition (true), the return value is -1
• For a non valid condition (false), the return value is 0

Note: All those arguments can be combining to create anoter one like: Equal or larger then ( => )

Isolate arguments

Each time we need to verify a condition, isolate it between brackets

• = (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 return, the use of the mathematical argument «ABS» can be use.

=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 fo the Depth is 1

From that simple example, it is easy to understand that we need to multiply the return value by the desire quantity.

Base 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 conditions need to be validating, it is necessary to use the operators «AND» … «OR». Notice arguments has been combine 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 easier and the reading too.

2. It could 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 formula, I resume the process in four steps. Following those steps will help you in the writing of complex formula.

This resume 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