# Moving a particle in Mayavi2

I have explained in my previous post “how to plot a particle at specified position”. If we need to move particle from one place to another we may also want to change the data of the plot and update the plot without having to recreate the entire visualization.

Instead of recreating entire visualization, mlab provide a very convenient way to change the data of an existing mlab visualization.

Consider simple example:

import numpy from enthought.mayavi import mlab mlab.figure(1, bgcolor=(0, 0, 0), size=(1300, 700)) mlab.clf() x = numpy.array([1,1.2]) y = numpy.array([1,1.2]) z = numpy.array([1,1.2]) s = numpy.array([0.3,0.5]) g=mlab.points3d(x,y,z) ms =g.mlab_source for i in range(10): y=y+0.1 ms.set(y=y) #updating y value for i in range(10): z=z+0.1 ms.set(z=z) #updating z value for i in range(10): x=x+0.1 ms.set(x=x) #updating x value mlab.show()

The key here is that the g object above has a special attribute called mlab_source. This sub-object allows us to manipulate the points and scalars.

The only thing to keep in mind here is that the shape of x,y,z should not be changed. If multiple values have to be changed, you can use the set method of the mlab_source.

Particle moving video:

I tried it, I like it very much. thank u !