# Output files

The APM Solver and Preprocessor can output files in .csv, .vtu, and .dat file formats. The .csv files can be opened with any text editor or data processing software such as MATLAB or RStudio. The .vtu files are specific to ParaView. ParaView is an open-source, multi-platform data analysis and visualization application which can be downloaded from https://www.paraview.org/download/. The .dat files are specific to Tecplot. Tecplot is the name of a family of visualization & analysis software tools developed by Tecplot, Inc.
To enable or disable ParaView or Tecplot output change the `paraview_output` and `tecplot_output` options in the .conf file.

## Output file descriptions

 File Description _body_panels.vtu_body_panels.dat Files in .vtu, or .dat file formats which contain the source strengths, doublet strengths, reference velocities, relative velocities and the pressure coefficient of the body elements. Created by the APM Solver. _wake_panels.vtu_wake_panels.dat Files in .vtu, or .dat file formats which contain the doublet strengths of the wake elements. Created by the APM Solver. .loads File in space delimited file format which contains the integrated loads of the body. Created by the APM Solver. .mdl File in space delimited file format which contains the element types, vertices, and neighbours. Created by the APM preprocessor and used by the APM Solver. .checkpoint File in binary file format which contains the latest solution. Created by the APM Solver. .json File in .json file format which can be opened by the APM Viewer. The file contains the mesh, the body and wake panels as well as the integrated loads. Created by the APM Preprocessor/Solver.
The structure of an example .loads file is shown below:
Timestep Time CFx CFy CFz CMx CMy CMz CL CD CC
0 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000
1 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000
2 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000
3 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000 0.0000000000
...