XVEL, YVEL, ZVEL

matrices of the velocity components
required arguments

X, Y, Z

vectors defining the rectangular domain
required arguments

L1,L2,
C1,C2,
P1,P2

integer values of gridpoints defining first and last line,
integer values of gridpoints defining first and last column
integer values of gridpoints defining first and last page
of part of domain to be investigated, optional arguments

plot

3d coneplot of velocity field