[solved] Nested Loops

Evertox

Hi Sebasstian,

Is it possible to create Nested Loops as used within E-Prime? I have existing projects that I would like to convert into OpenSesame to use instead. It seems that without using a sequence for every loop, all cycles need to be completed.

In the past I used the E-Prime Sampling functionality that could run 1 random sample from the total cycle list. I don't seem to find an option to do this without using inline scripting.

Is there a plan to incorporate this functionality into future versions?

Thanks

Anthony McGuffie

Edwin

Hi Anthony,

It is possible to only run one random cycle within a loop by using the 'Repeat' option. For example, if you were to run a loop with 5 cycles, you could set the order to random and the number of repeats to 0.20. In this case one random cycle would be run.

I admit this is a bit of a workaround, but you could use this to get your experiments going for now. I'll leave it to Sebastiaan to answer your question regarding the future implementations

Hope this helps!

Edwin

Evertox

Hi Edwin,

Thanks for the quick response. I just tried it and it does work ok. I did not know the repeat function could be set to less than 1.

Cheers

Anthony

sebastiaan

I admit this is a bit of a workaround, but you could use this to get your experiments going for now. I'll leave it to Sebastiaan to answer your question regarding the future implementations

Yes, the repeat value is a bit awkward, although it should work. For 0.27 there are some new features in the loop item, but not this particular one. I've marked it as a feature request for 0.28 (I've already declared an informal "feature freeze" for 0.27): https://github.com/smathot/OpenSesame/issues/101

Cheers!

Evertox

Hi Sebastiaan,

Please note:

I have just tried to set the number of cycles to 3 and the repeat to 0.33 to provide 1 random cycle and it shows a "zero or negative length" error.

Cheers

Anthony

lvanderlinden

Hi Anthony,

That's just because 3 times 0.33 is 0.99. More specifically, the number of cycles that is actually executed is always the floor of the input number. The floor of 0.99 is 0.
Therefore, if you set the repeat to 0.34 (0.34 * 3 = 1.02), 1 random cycle should be executed.

Does this solve your problem?

Best wishes,

Lotje

Evertox

Hi Lotje,

I did try to 'round' the result to 1 but I wasn't sure whether doing this would cause the loop to produce errors in lengthy experiments. The project I am creating at present has 6 x 150 trials with 4 nested loops so i raised this issue before participants starting testing.

Cheers

Anthony