Plot streamline by Tecplot
 

Hello,

I am new to Tecplot. I just want to plot streamline by Tecplot, so I prepared the data file for Tecplot:
1) Format
VARIABLES = rg, zg, ur, uz
ZONE T = "velocity field", I = 40 , J = 400 ,F = point
(rg, zg indicate the mesh; ur, uz are the velocity.)
2) I made new 2-d arrays for all above variables on the nodes (Since I used staggered grid, I recalculated ur and uz on each node.)
rg(i,j)....

When I load the data and choose "2D cartesian", the plot is messy and weird. When I try to draw streamline, it said "Poit is outside of any zone" or "Not all points along the rake were within the data field"

Any idea? Many many thanks.