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dke-questions > gradient vectors option
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Aug 14, 2020 02:08 PM | XING GAN - 13041128211
gradient vectors option
Dear experts
After I read the dke operation document, I still don't know much about the gradient vectors option in dke. Can you tell me what it means and how I should choose.
Looking forward to your reply.
sincerely
GAN XING
GUIZHOU UNIVERTY
After I read the dke operation document, I still don't know much about the gradient vectors option in dke. Can you tell me what it means and how I should choose.
Looking forward to your reply.
sincerely
GAN XING
GUIZHOU UNIVERTY
Aug 21, 2020 01:08 PM | Siddhartha Dhiman - Medical University of South Carolina
RE: gradient vectors option
Originally posted by XING GAN:
Hi Gan Xing,
The gradient file contains the X, Y, and Z diffusion-weighted (DW) gradient scheme. Each row consists of 3 tab-separated floating-point columns corresponding to the X, Y and Z components of the gradient scheme, where every row corresponds to the the DW scheme for non-B0 shells.
Non-B0 shells (B1000 and B2000) will have the same gradients, which should be stored in a gradients.txt file. For example, a 30 direction DKI dataset consisting of 10 B0s, 30 B1000s, and 30 B2000s will have a gradients.txt file with 30 rows and 3 columns
The gradient vector option in DKE points to the path of this gradients.txt file.
Having said that, I must warn you that DKE has been deprecated in favor of our new DTI/DKI/FBI/FBWM pipeline called PyDesigner - it is easier to run and requires less data preparation than DKE, whilst enabling slightly better tensor estimation. You may find PyDesigner at https://github.com/m-ama/PyDesigner
Best,
Sid
Dear experts
After I read the dke operation document, I still don't know much about the gradient vectors option in dke. Can you tell me what it means and how I should choose.
Looking forward to your reply.
sincerely
GAN XING
GUIZHOU UNIVERTY
After I read the dke operation document, I still don't know much about the gradient vectors option in dke. Can you tell me what it means and how I should choose.
Looking forward to your reply.
sincerely
GAN XING
GUIZHOU UNIVERTY
Hi Gan Xing,
The gradient file contains the X, Y, and Z diffusion-weighted (DW) gradient scheme. Each row consists of 3 tab-separated floating-point columns corresponding to the X, Y and Z components of the gradient scheme, where every row corresponds to the the DW scheme for non-B0 shells.
Non-B0 shells (B1000 and B2000) will have the same gradients, which should be stored in a gradients.txt file. For example, a 30 direction DKI dataset consisting of 10 B0s, 30 B1000s, and 30 B2000s will have a gradients.txt file with 30 rows and 3 columns
The gradient vector option in DKE points to the path of this gradients.txt file.
Having said that, I must warn you that DKE has been deprecated in favor of our new DTI/DKI/FBI/FBWM pipeline called PyDesigner - it is easier to run and requires less data preparation than DKE, whilst enabling slightly better tensor estimation. You may find PyDesigner at https://github.com/m-ama/PyDesigner
Best,
Sid