Newbie problems with exporting plot data

[Paweł Jasiński]

Hello.
I've recently started working with OpenSim. One of the things I wanted to do, was to gather data concerning relations between muscle fibre length and joint angles in a human arm. While GUI offers nice and intuitive ways to plot correct graphs, and to export them into formats understood by OpenSim, I can't seem to find a way to prepare them for use with Excel/MatLab.
Any help would be appreciated, and thanks in advance!

[Thomas Uchida]

Please refer to the User's Guide on Confluence (https://simtk-confluence.stanford.edu/d ... %27s+Guide)---specifically, see the "Exporting and Printing" page in the "Plotting" section: https://simtk-confluence.stanford.edu/d ... d+Printing.

[Paweł Jasiński]

That's actually exactly what I did- and I had no problems exporting it as an .sto or .mot file, but I can't seem to get them to work in any other program than OpenSim itself.

[Thomas Uchida]

.sto and .mot files are tab delimited; they can be opened/imported in Excel and MATLAB. You can also open them in a text editor like Notepad++. I would try opening reference files found in your OpenSim installation directory (e.g., C:\OpenSim 3.3\Models\Arm26\OutputReference\ForwardDynamics\PhysiologicalResults) to determine whether the issue is with opening a file of this type or saving from the plotter.

[Paweł Jasiński]

Thanks for the suggestion!
The problem seems to lie in exporting the data itself. Example files work as intended, but the ones created by exporting data from a plot into a *.sto or *.mot file are empty, and weigh 0b.

[Thomas Uchida]

I did not encounter an issue. Here were my steps:
- start OpenSim 3.3 GUI
- open arm26.osim model
- Tools -> Plot...
- Y-Quantity -> fiber-length
- Muscles... -> BRA
- X-Quantity -> r_elbow_flex
- click "Add" button
- right-click plot area -> Export Data...
The resulting file can be opened in Excel and generates the same plot shown in the GUI.