Thanks for your guidance @lassoan . I have wrote the python script to convert the .tag file to .fcsv file and it can be loaded in 3D slicer.
I have two fiducial dataset (one is preoperative MRI and one is 3D ultrasound) and I want to calculate the displacement vector for each fiducial pair. I am wondering if there is a method to calculate the displacement vector for each fiducial point and show all the vectors in the slice and 3D scene. My final goal is to manually check the outlier for each fiducial pairs in both image slice. Thanks.
For example in the two fcsv files, we have:
vtkMRMLMarkupsFiducialNode_0,50.164402 -31.719656 34.845306,-5.771,-11.195,9.070,1.000,1,1,0,F1-1,F1-3, …
vtkMRMLMarkupsFiducialNode_0,48.972829 -32.396878 34.952277,0.000,0.000,0.000,1.000,1,1,0,M1-2,
The displacement vector = (x1 - x2, y1 - y2, z1 - z2) for each pair. I could calculate all the displacement vectors from two fiducial sets and I would like to load the result to 3D slicer, and able to visualize all the vectors automatically. The result is similar to the following figure (refer from another question “calculating-the-displacement-between-two-models”). And I am not sure if this can be finished all in python.
Thanks again for your help.