Hi Anita, you need to check the math on your design. You have 86 stimuli. Each stimulus requires 0.5s for presentation and 2 sec for null means 215sec total (minimum). But you have TR=2 and Ntp=86 meaning a run of only 172 sec. You will need to increase the number of TRs or decrease the number of stimuli. Note that 215 is the minimum. You may need a bit more to get good results. doug
Anita Cservenka wrote:
Hi everyone, I'm using optseq2 and a tnullmin of 2 seconds to force 2 seconds between each event for my paradigm, but I get a "segmentation fault" error. Here's my command line below. I didn't specify a tnullmax, so that I would avoid any errors by specifying both. I tried other values for tnullmin like 1, which did work and 1.5, which also did not work. Ideally, the paradigm I would like to model listed in a paper that fixation was jittered 2-10 seconds between stimuli, but 2 seconds does not work for me. Do you know why this might be? Thanks.
optseq2 --nsearch 1000 --nkeep 2 --pctupdate 10 --ntp 86 --tr 2 --psdwin 0 12 0.5 --ev emotion 0.5 60 --ev calm 0.5 26 --tnullmin 2 --cost eff --o emotion
INFO: Setting srand48() seed to 345330
optseq2
$Id: optseq2.c,v 2.21.2.1 2011/04/21 19:50:06 greve Exp $ NoSearch = 0 nSearch = 1000
nKeep = 2
PctUpdate = 10.000000
nCB1Opt = 0
seed = 345330
Ntp = 86
TR = 2
TPreScan = 0
PSD Window = 0 12 0.5
nEvTypes = 2
EvNo Label Duration nRepsNom
1 emotion 0.500 60
2 calm 0.500 26
PctVarEvReps = 0
VarEvRepsPerCond = 0
PolyOrder = -1
tNullMax = -1
tNullMin = 2
outstem = emotion
AR1 = 0
No refractory penalty
Cost = eff
OutStem = emotion
Summary File = emotion.sum
nTaskAvgs = 48
INFO: LogFile is emotion.log
outstem = emotion
Segmentation fault
-Anita
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