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Hello all,</div>
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I simulated the diffusion signal coming from a synthetic substrate by using two acquisition schemes: one with 300 acquisitions, the other one with 3900 acquisitions. I am trying to execute the fit of such a signal with the models ActiveAx and AxCaliber by using
the following commands:</div>
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for ActiveAx:</div>
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cat ${FNAMEINFO[i]}_NOISE.Bfloat | modelfit -fitmodel mmwmdfixed -fitalgorithm mcmc -burnin 1000 -samples 100 \
<div>-interval 500 -noisemodel rician -sigma ${SIGMA} -schemefile ${SCHEMEFILE} | chunkstats -chunksize 16 -samples 100 \</div>
-mean > ${FNAMEINFO[i]}_MMWMD.Bfloat<br>
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for AxCaliber: </div>
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cat ${FNAMEINFO[i]}_NOISE.Bfloat | modelfit -fitmodel TensorGDRCylinders -fitalgorithm MULTIRUNLM -samples 1000 -burnin 1000 \
<div>-interval 500 -noisemodel rician -sigma ${SIGMA} -schemefile ${SCHEMEFILE} | chunkstats -chunksize 16 -samples 1000 \</div>
-mean > ${FNAMEINFO[i]}_AxCaliber.Bfloat<br>
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With both the acquisition schemes </div>
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In the case of ActiveAx <span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">the output is only:</span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br>
</span></div>
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mar 17, 2021 1:04:21 PM optimizers.LM_Minimizer minimise</div>
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AVVERTENZA: optimizers.MarquardtMinimiserNonConvergenceException: Exceeded maximum number of iterations: 5000</div>
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In the case of AxCaliber:</div>
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mar 15, 2021 11:13:06 AM optimizers.LM_Minimizer minimise
<div>AVVERTENZA: optimizers.MarquardtMinimiserException: Infinite objective function in mrqcof.</div>
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How can I fix such issues?</div>
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Thanks in advance for your help</div>
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