On Sat, Dec 7, 2024 at 02:23 AM, Tony Casey wrote:

It seems to make no difference on a PC,  but it may be that the Mac version has stricter syntax checking. Are you using the Mac version of LTspice, or are you using the PC version under Wine (or equivalent) on the Mac? Saying "latest version" might be confusing, as there is now a beta version of LTspice available (24.1.x), whereas the current release version is 24.0.12. It's better to be specific about what version(s) you're using on each machine.

If that doesn't reveal anything, perhaps you would consider uploading your file(s), so other people could check. We certainly have a few Mac users in this group.

I tested the .func directive on macOS LTspice 17.2.4, and it works as expected, using either parentheses or curly braces to enclose the function's expression. I stepped the simulation to verify it was producing different values for the resistance.

 

I uploaded my schematic to mac_func_test.zip

 

HTH