StreamPlot3D

StreamPlot3D[{vx,vy,vz},{x,xmin,xmax},{y,ymin,ymax},{z,zmin,zmax}] plots streamlines for the vector field {vx,vy,vz} as functions of x, y and z.

StreamPlot3D[{vx,vy,vz},{x,y,z}∈reg] takes the variables {x,y,z} to be in the geometric region reg. 

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