topic IF function in Parameters in Inventor Forum

IF function in Parameters

spi82UU6 — Tue, 20 May 2025 08:28:26 GMT

It would be a very good thing if it was possible to use the "IF" function when specifying the values of the parameters. In many cases this would help the work. There are components where, for example, the pattern should be bound to a condition, this is very difficult or not possible at all without the "IF".

Re: IF function in Parameters

kacper.suchomski — Tue, 20 May 2025 09:03:27 GMT

It's possible. You can do it all with iLogic.

iLogic allows both assigning conditional values and linking parameters between files, which is useful e.g. in the above-mentioned patterns.

Re: IF function in Parameters

johnsonshiue — Tue, 20 May 2025 19:49:41 GMT

Hi! There is a way to write a parametric expression to do "if, then" but it largely depends on the complexity of the condition. Please share an example of the desirable "if, then." I would like to see if there is a parametric expression solution without using an iLogic rule.

Many thanks!

Re: IF function in Parameters

spi82UU6 — Wed, 21 May 2025 06:07:20 GMT

Hi,

I need only a simple if/then solution.

A = 10 mm
B = if "A=10" then "B=12" else "B=15"

Or

B = if(A=10;12;15) like in Excel 🙂

That's all.
Have a nice day,
Sandor

Re: IF function in Parameters

kacper.suchomski — Wed, 21 May 2025 08:26:26 GMT

If A=10 Then B=12 Else B=15 End If

You can paste this code into an iLogic rule.

Of course, you must replace the symbols with the actual names of the parameters.

Re: IF function in Parameters

aurel_e — Wed, 21 May 2025 10:31:25 GMT

Other users have shown previously creative ways to compensate for that...

In your case the B would be:

( 1 ul - sign(abs(A1 - 10 mm) - 0.001 mm) ) * 12 mm + sign(abs(A1 - 10 mm) - 0.001 mm) * 15 mm

Re: IF function in Parameters

johnsonshiue — Wed, 21 May 2025 21:05:00 GMT

Hi! There is a simpler equation to use for this case.

B=sign(( A / 1mm - 10 ul )) * 3mm + 12mm

Many thanks!

Re: IF function in Parameters

aurel_e — Thu, 22 May 2025 05:24:04 GMT

@johnsonshiue This is resulting 12 for A<10.

Re: IF function in Parameters

SBix26 — Thu, 22 May 2025 19:33:15 GMT

In @johnsonshiue 's equation, just add the absolute value:

B=sign(abs( A / 1mm - 10 ul )) * 3mm + 12mm

B is 15 unless A is exactly 10.

I, too, thought that the sign function would return -1 for negative, 0 for 0, and +1 for positive, but that's not the case; it returns +1 for > 0, 0 for <= 0

Sam B

Inventor Pro 2026.0.1 | Windows 11 Home 24H2

Re: IF function in Parameters

spi82UU6 — Fri, 23 May 2025 06:00:19 GMT

Thank you so much!