{Request} Wildcards in .wave statement

Hello JHerrmann, All assigned engineers are out of office currently. MStokowski will be back in the week of 1/5/2026 to answer your question!

Hi JHerrmann ,

This is already supported by string expressions in versions 24.1 and up.

From the Help:

.wave <filename.wav>|<string exprssion> <Nbits>  <SampleRate> V(out) [V(out2) ...]

and

String parameters only support the "+" operator for string concatenation, e.g:

.param variant = "_fast"
X23 PIN1 PIN2 {"U125D" + variant}

mike

I will test this as soon as possible (=tomorrow). As you show it, i guess [.step param variant list "_fast" "_slow" "_medium"] would also work as intended? That would really be something new (and useful!) - i searched all the internet, and even asked AI (MSCopilot) for it - but nobody knew something. From your point of view ("read the manual") it seems logical - but this kung fu (with + operator) is really somewhat unsual .. i guess... I come back to you, as soon as i have tested it. Thanks for now. Very much appreciated - really. 

Hi JHerrmann ,

Concatenation, I believe, is commonly achieved with either an ampersand (&) or plus (+), depending on the application language. Note, also, from the help:

Note that numerical parameters implicitly convert to strings. The conversion of non-integers is unspecified. Implicit conversion takes place before performing any operations, for instance

.param text = 1 + 3 + "text"

yields "13text", not "4text".

This inference precludes the need to convert an integer to a string character, as one would have to do in, say, Excel.

mike

Hello Mike...

Sorry for coming back here a bit late. I have tried your suggestions, but i am not even able to set string variables. ".param text="xyz"" or ".param text= 1 + 2 + 3 + "text" leads to "couldn't resolve parameter" errors. Using plain numbers instead of text leads to invalid Stoi errors in the .wav command.  That doesn't kill my project, since i have switched to batch-mode-simulation and bash/batch programming of the netlist instead. Working under Linux, i am able to modify the netlists and start runs with parameters and wav-names as i want. I believe, for my project, this is the definite solution, but i am still interested in what you suggested. But as of now: it simply doesn't work. Sorry ... either i am doing something wrong (tested different variations - also with "&") or it simply doesn't work. LTSpice version FIY is: 24.0.9 - i will try to get a newer Version, next time i am on Windows. This could delay until the weekend i believe, since i am very busy atm.

Hi JHerrmann ,

Huh, I'd better look at this. Thanks.

mike

yepp - i think the fault is on my side, since i am running version 24.0.9 - the recent version is 26. So... Maybe its just, that i am a bit late regarding my updates. I come back to you, as soon as i am on windows again. By the way: Bash-Programming of the netlists is like... well.. LTSpice as Atombomb. I am able to deform the netlists in every direction i want. Prototyping: As usual with LTSpice -- Mass Production of Output: Per Bash- Netlists - and LTSpice in Batchmode...Definitely the way to go (besides Python-LTSpice etc..) if you are mass-processing... By the way: Are you aware of any useful tools to convert RAW into WAV?

Hi JHerrmann ,

If you are using LTspice 24.0.9, it will not work. You must use version 24.1 or higher to use string parameters. As there are quite a few stability fixes in the latest version, 26.0.1, I would highly recommend updating. 

MStokowski said:

This is already supported by string expressions in versions 24.1 and up.

mike

Yes. Sorry about the concurrent reply.