11. Visualization and post processing

11.1. Introduction

DEVSIM is able to create files for visualization tools. Information about acquiring these tools are presented in Install external software tools.

11.2. Visualization software

11.2.1. Overview

The tools in Table 11.1 can read the file Tecplot and VTK Formats.

Table 11.1 Open source visualization tools
`ParaView`	visualization tool available at https://paraview.org.
`VisIt`	visualization tool available from https://visit-dav.github.io/visit-website/

11.2.2. Using `ParaView`

The devsim.write_devices() is used to create an ASCII file suitable for use in ParaView. Edge quantities are interpolated onto the node positions in the resulting structure. Element edge quantities are interpolated onto the centers of each triangle or tetrahedron in the mesh.

write_devices(file="mos_2d_dd", type="vtk")

One vtu file per device region will be created, as well as a vtm file which may be used to load all of the device regions into ParaView.

11.2.3. Using `VisIt`

VisIt supports reading the Tecplot and ParaView formats. When using the vtk option on the devsim.write_devices(), a file with a visit filename extension is created to load the files created for ParaView.

11.3. Reducing file sizes

Based on a contribution by [@simbilod](https://github.com/simbilod) devsim.write_devices() now supports reducing the file size of data files by allowing users to specify a callback function to reduce data usage. In this example, only the NetDoping field is written to the Tecplot data file.

devsim.write_devices(
    file="mesh2d_reduced.tec",
    type="tecplot",
    include_test=lambda x: x in ("NetDoping",),
)

11.4. Post processing

DEVSIM has several commands for getting information on the mesh. Those related to post processing are described in Model commands and Geometry commands.

See Loading and saving results for information about loading and saving mesh information to a file.

11.4.1. Index information

The coordinate_index and node_index are default node models created on a region (Table 5.1}). The edge_index is a default edge models created on a region Table 5.2.

11.4.2. Element node list

The devsim.get_element_node_list() retrieves a list of nodes for every element on a region, contact, or interface.