[Mristudio-users] FW: DTI Gradient Orientation table (matrix)

[Hyunmi Kim, M.D.]

Dear Sir;
You have my many thanks!
Hyunmi 

-----Original Message-----
From: mristudio-users-bounces at mristudio.org
[mailto:mristudio-users-bounces at mristudio.org] On Behalf Of Carl Helmick
Sent: Thursday, August 14, 2008 7:04 AM
To: mristudio-users at mristudio.org
Subject: Re: [Mristudio-users] FW: DTI Gradient Orientation table
(matrix)


The gradient orientation table is an ASCII text file and is located on  
the scanner.  It is called "tensor.dat" and is located in /usr/g/bin.   
The file is made up such that there is a line with a single number  
indicating number of directions, then a line for each gradient  
combination to get that number of directions.  For example, for 6, 7,  
and 8 directions you will see:

6
0.707 0.0 0.707
-0.707 0.0 0.707
0.0 0.707 0.707
0.0 0.707 -0.707
0.707 0.707 0.0
-0.707 0.707 0.0
7
1.0 0.0 0.0
0.333 0.943 0.0
-0.333 0.472 0.817
0.577 -0.817 0.0
0.333 -0.472 0.817
-0.577 -0.407 0.707
0.577 0.407 0.707
8
1.0 0.0 0.0
0.333 0.943 0.0
-0.333 0.472 0.817
0.577 -0.817 0.0
0.333 -0.472 0.817
-0.577 -0.407 0.707
0.577 0.407 0.707
0.0 1.0 0.0
This corresponds to gradient amplitudes in X, Y, and Z directions.

Here is the one from a GE Signa 1.5T (v.12):