For example,

1.  I want to output the all points where{x=0.1},such as (0.1,0.1,0.1)

2.  I want to obtain the CELLS including points in step1;such as (12,13,56,23)

3.  I want to obtain the values(p,u) in the *.vtk file

I am using ipython,but I have no idea.

Here is the attachment

What should I do?

Thank you advance.