Good afternoon DIPY experts! I am in the process of performing free water elimination (FWE) on an in-house HYDI dataset using DIPY. In my research regarding how to develop an effective FWE pipeline, I learned that it is necessary to exclude voxels with a high water volume fraction, which can be done by excluding voxels with FA values linked to volume fractions above 0.7. In creating my free-water corrected scalar maps, I have done this for my FA maps with the following lines of code: FA = fwdtifit.fa F = fwdtifit.f FA[F > 0.7] = 0 It is still unclear to me as to how I should go about (1) extracting my other free-water corrected DTI scalar maps (i.e. MD, RD, AD), as well as (2) how I should go about controlling for these high water volume fractions voxels in non-FA scalars. To resolve the latter source of confusion, should I just exclude non-FA scalar values associated with a volume fraction exceeding 0.7? I am planning to attempt to get the volume-fraction corrected, free-water eliminated scalar maps with the following lines of code: MD = fwdtifit.md MD[MD > 0.7] = 0 RD = fwdtifit.rd RD[RD > 0.7] = 0 AD = fwdtifit.ad AD[AD > 0.7] = 0 Does this code make sense for what I need it for? That is, is this the correct way to be handling these issues? Also, might someone be able to explain to me what the ".f" function does? Thank you so much for all of your help and consideration! Kind regards, Linda Hoffman