Dear Suoqing Ji:
With a combination of center [0,0,0] and adjusting the width w, I was able to eliminate all the warnings mentioned earlier. But the off axis slice plots still wont give me a desired result.
Plot available on the drive below below.
The two plots L(010),N(0,0,1).png and L(101),N(001).png are plotted for x-z plane and viewing angle of 45 degrees but both are drastically different from each other. In fact the off axis slice plots (L(101),N(001).png) is not in the x-z plane either.
I am aiming for a plot similar to vector_rotate.png which is same as vector_original.png but rotated/viewed at an angle.
The vector_rotate.png was created using the python image library. I was hoping if yt has any similar options with off axis which would tilt the vector plots and fill all the vector grids (which cannot be done using PIL).
The script (yt_velocity_fields.py) and sample data file (Expl_Bt101.mtx.tar.gz) is available on drive link for your reference.
Thanks in advance and my sincere apologies for repeated queries. But this is extremely critical in reproducing my result and putting it for publication.