How many volumes are there in your data? From this error message it looks like there is only 1, but asl_file is expecting 2: a label and control image. Michael On 17 Aug 2017, at 05:49, Archana Malagi <[log in to unmask]<mailto:[log in to unmask]>> wrote: Dear FSL user, I have followed BASIL tutorials but following getting error: [fsl@fslvm6 delay_1]$ asl_file --data=data --ntis=1 --iaf=tc --diff --out=diffdata --mean=diffdata_mean Number of voxels is:589824 Number of repeats in data is:0 Warning: spare measurements found at end of data! Number of measurements discarded from end is: 1 An exception has been thrown Logic error:- detected by Newmat: incompatible submatrix dimension Trace: SubMatrix(evaluate). Please find attachment containing snapshot data, calibrated, and 3D T1 images. There is only single delay of 1s. -- Archana V. Malagi, PhD Scholar, Centre for Biomedical Engineering, IIT New Delhi-110 016 [log in to unmask]<mailto:[log in to unmask]> <calib.jpg><data.jpg><optimized_struct.jpg> --- Michael Chappell MEng DPhil W: http://www.ibme.ox.ac.uk/qubic T: +44 1865 617657 Associate Professor, Institute of Biomedical Engineering, University of Oxford. http://www.ibme.ox.ac.uk Director of Training, EPSRC-MRC CDT in Biomedical Imaging http://www.onbicdt.ox.ac.uk Governing Body Fellow, Wolfson College, Oxford. http://www.wolfson.ox.ac.uk Research Fellow, FMRIB Centre http://www.fmrib.ox.ac.uk