You don't need to write an equation, just use the option "Up to Reference" under linear pattern.
There is an example of this here: SWW18 Presentation - All The Small Things
Save you a ton of time!
EDIT: for my example, I created a plane that was offset from the end of the part to use as the "reference" for the pattern.
2nd EDIT: Download the sample files and look for the room assembly, I used this technique to place the 2x4's in the walls.
I just watched your presentation. Awesome amount of info. Thank you!
I used the Up To Referance and it works very well and it is much less work.
Is it possible to get the 2 outer most points fixed (2 in from edge) and have the inner very by count AND distance (no les then 12 and no greater then16)?
I did find the "Instances to Vary" switch but its still not quite what I want.
Here is something that you can try -
Set the first hole at a specific distance from the one end,
Set the last hole at a specific distance from the other end,
Set a plane through the center of the last hole,
Pattern the first hole, using the new plane for your "up to reference"
Both holes on the ends will stay in place, and everything between them will be free to move.
Not sure about varying the inside distance - if you set it at 14", it would be easy to vary the quantity.
I may have to ponder this a little more . . .
Thanks! I'm glad to hear it's not just me see the same thing.
I did do exactly the same step you suggested (probably as you were typing).
To give you credit, the Up to Reference does work but the distance can very (12-16) and count can vary (0-n, Odd and even counts)