Streamlines

Streamlines visualize the movement of a set of massless particles through the vector field. The points are tracked by treating the vector field as a velocity field and integrating it. Each path is tracked until the path leaves the input field or a maximum number of steps is reached. You can use keywords to set the number of particles, the integration step size, and the number of steps.

The following example shows the streamlines produced by a random vector field. To create these streamlines in IDL, enter the following code at the Command Line:

u = RANDOMU(1,20,20) - 0.5 
v = RANDOMU(2,20,20) - 0.5 
IVECTOR, u, v, /STREAMLINES, $ 
   X_STREAMPARTICLES=10, Y_STREAMPARTICLES=10, $ 
   HEAD_SIZE=0.1, STREAMLINE_NSTEPS=200 

Figure 17-3: Streamlines in iVector

ivector_streamlines.gif

Note
For details on the streamline keywords, see "IVECTOR" (IDL Reference Guide). Also see Adding and Modifying Streamlines.