How to pick nodes,areas etc. in pyVista

[bedermaus]

I want to apply load on some areas, nodes via pyVista, is it possible? Like, for example user open model via pymapdl in pyvista gui and pick cells. PyVista return coordinates of every node, but how to transform it to mapdl format? I know that in mapdl every node, area has an number, but how to get all this staff via pymapdl? Thanks for reply.

[mikerife]

Hi @bedermaus Picking in a PyVista plot is on the development list, see this Issue: #786 For now either use select logic (maybe a lot of select logic!) or you can use the mapdl.open_gui() to inspect the model as you go.
Mike

[bedermaus]

@germa89 Thanks. Yes, looks better.

About parameter ' Found_nodes_number' - i didn't know how to get list of all nodes in format [NODE; X; Y; Z], so i built it from node_list = mapdl.nlist(node1='all', lcoord='XYZ', sort1='NODE') which returns string:

LIST ALL SELECTED NODES.   DSYS=      0
 SORT TABLE ON  NODE            

 *** ANSYS - ENGINEERING ANALYSIS SYSTEM  RELEASE 2021 R1          21.1     ***
 DISTRIBUTED ANSYS Mechanical Enterprise                       

 00000000  VERSION=WINDOWS x64   12:17:15  MAY 17, 2022 CP=      5.094

   NODE        X                   Y                   Z
        1   -120.948132969        -55.5000000000         80.0000000000     
        2   -118.968132969        -55.5000000000         80.0000000000     
        3   -116.988132969        -55.5000000000         80.0000000000     
        4   -115.008132969        -55.5000000000         80.0000000000
...      

Just right now realized about
mapdl.mesh.nodes

Did a lot of shit work haha,
Anyway, thanks a lot for help...

Also, #599 is it still alive? because I have the same right now

[germa89]

yeah... I have done some much useless parsing in my life.. I feel related.

About #599... there is no news, so if you can post on it (list of packages, commands used, etc) it will help

[bedermaus]

Hi @germa89
I found a solution of this problem in rst.py
Here is a problem.
https://github.com/pyansys/pymapdl-reader/blob/a372434d32bee36f9856a50a40136c65cd0a280b/ansys/mapdl/reader/rst.py#L2965

Function doing only first loop with selected n_frames (100 as default), then it going down to default frames like in pyvista ( I think its less then 10, thats why its going too fast). In gif format its ok, because browser or your GIFViever just loop saved first loop by itself.

I just deleted this line and everything is works. Check it out. Im sure that you know better than me how to fix it in best way.

[germa89]

Hi @bedermaus

I think your comment is super helpful! I will have a look and will try to fix it along this week.

Kind regards!

[bedermaus]

@germa89

In general, i found how to fix it.
Before i said that i just deleted a line with first_loop = False, it means that when window with animation opens it recording to movie_filename, so if you will leave a window opened, file could get infinity memory on disk....
In rst.py i found the same structure, but for another method - _animate_point_scalars
(https://github.com/pyansys/pymapdl-reader/blob/a372434d32bee36f9856a50a40136c65cd0a280b/ansys/mapdl/reader/rst.py#L2991)
And if you will look into this function, you will see here part of code :

        if off_screen:
            twait = 0
        else:
            twait = 1/fps

        first_loop = True
        while self._animating:
            for i, data in enumerate(scalars):
                tstart_render = time.time()
                copied_mesh.active_scalars[:] = data

                if text is not None:
                    # 2 maps to vtk.vtkCornerAnnotation.UpperLeft
                    plotter.textActor.SetText(2, text[i])

                # at max supported framerate
                plotter.update(1, force_redraw=True)
                if not self._animating:
                    break

                if movie_filename and first_loop:
                    plotter.write_frame()

                # wait to maintain desired frame rate
                telap = time.time() - tstart_render
                if telap < twait:
                    time.sleep(twait - telap)

            first_loop = False
            if not loop:
                break

If you will compare with function which i noticed before, you will see that them looks indentical, but in first missing time variables.
(wich are responsible for # wait to maintain desired frame rate)
So, i think everything is completlly clear right now.

So i just copied all 'time' operations from this function to function from reply above, but changed parameter fps -> n_frames.

Everything is working perfect. Now if you want to save gif file it will record only first loop and will not take a lot of place, and animation in pyvista will be with the same framerate as n_frames.