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Data Export
Graham Ashton
1 Posts

Hi

I am persuading students at the European School of Osteopathy, Maidstone, England to use Tracker as a Video Goniometry tool. Human subjects have landmarks of interest identified with stickers or felt pen and are then asked to perform specific movements. These movements are either photographed or videoed, the results being imported into tracker. Point masses are then used to track the movement of the marks. Point mass data is then exported to a spread sheet for further analysis.

Currently, the students are copy and pasting point mass data one point mass at a time from tracker to a spread sheet. Not normally a problem if only a few point masses have been defined but .... Recently a student has marked all 12 thoracic spinous processes and all 5 lumbar spinous processes. as you can imagine, copy and pasting in this way for 17 point masses is .......

Is there any way that the export data function could have an option "all..." with sub options
"t-horizontal"
"t-vertical"
"t-separated"

giving output formats:

t-horizontal
                t1                    t2                    t3
                x          y          x          y          x          y          
Mass_A    #### ####  #### #### #### ####
Mass_B    #### ####  #### #### #### ####
Mass_c    #### ####  #### #### #### ####

t-vertical

        Mass_A           Mass_B         Mass_C        
        x          y          x          y        x          y          
t1    #### ####  #### #### #### ####
t2    #### ####  #### #### #### ####
t3    #### ####  #### #### #### ####

t-separated
                                    
                      x          y          
t1   Mass_A    #### ####  
      Mass_B    #### ####  
      Mass_C    #### ####
t2   Mass_A    #### ####  
      Mass_B    #### ####  
      Mass_C    #### ####  
t3   Mass_A    #### ####  
      Mass_B    #### ####  
      Mass_C    #### ####

I don't doubt there are many people reading this thinking "why don't you write your own widget" - unfortunately my programming skills are limited to working with structured basic!

Hope this is the sort of thing this forum is intended for.

Many Regards

Graham Ashton
Biomechanics Lecturer ESO


Replies to Data Export

Re: Data Export -
Douglas Brown Avatar
Douglas Brown
449 Posts

Hi Graham,

There is a way your students can export the combined data from several tracks right now :-)

1. Track all the points of interest--mass A, B, C, etc.

2. Set the Plot View to plot x versus t (the default) for mass A.

3. Right-click the plot and choose Compare With|mass B. This plots the mass B data along with mass A.

4. Repeat to compare with mass C, D, etc. Now all masses are plotted together.

5. Double-click the plot (or right-click and choose Analyze...) to analyze the data in Data Tool. The Data Tool tab will be named "mass_A" but you will see ALL the plotted data in the data table. (The mass A data is labelled "x", the other masses are labelled with numerical subscripts.)

6. Change the Tracker plot to y versus t and double-click it again to transfer the data to data Tool. The Data Tooltab will now have both x and y data for all tracks.

7. Rearrange the columns in the Data Tool table by dragging their headers so they are in your desired order t, x, y, x1, y1, x2, y2,...

8. In Data Tool, you can either choose the File|Export Data.. menu item to write the (tab-delimited) data to a text file or the Edit|Copy|Data item to copy it to the clipboard for pasting.

The exported data is in your "t-vertical" format, which is fairly standard. I hesitate to make your other format options available as a standard feature because they might simply confuse some students!

I hope this helps :-D  Doug



Re: Re: Data Export -
Doug Marsh
1 Posts

Hi Doug,

There's a minor bug with this process. If the point mass coordinates are too close together, then some points may get missed in the Data Tool table. For example, if there are 12 point masses, and three have x coordinates that coincide, or closely coincide, the table may only show 9 point masses. If you double click on the graph again, then it seems to include all 12. However, the order is not the same as the original numerical order of the point masses. You have to manually check to see the correct sequence of the results.

Doug Marsh



Re: Re: Re: Data Export -
Douglas Brown Avatar
Douglas Brown
449 Posts

Hi Doug,

Thanks for the feedback. I was able to reproduce the problem and will see if I can squash this bug immediately!

Doug



Re: Re: Data Export -
Seakay XIE
2 Posts

Hi, I did use the way you mentioned. However, I am doing a project with a number of point mass to be tracked, and I wonder if there is a way to select all points in the "Compare with" menu? Also, the track control box and the "compare with" box cannot be displayed properly when there are too many point masses (the box is too long to be placed in the monitor). The shape of the boxes cannot be adjusted to fit the monitor.  I will be grateful to see these issues be fixed. Thank you very much for the efforts on creating this amazing tool!



Re: Re: Re: Data Export -
Douglas Brown Avatar
Douglas Brown
449 Posts

Too many point masses to display properly in the track control? How many are you talking about? Doug


> I am doing a project with a number of point mass to be
> tracked, and I wonder if there is a way to select
> all points in the "Compare with" menu? Also, the track
> control box and the "compare with" box cannot be displayed
> properly when there are too many point masses (the
> box is too long to be placed in the monitor). The
> shape of the boxes cannot be adjusted to fit the monitor.



Re: Re: Re: Re: Data Export -
Seakay XIE
2 Posts

Hi! I am doing with more than 100 points. While a usual size monitor can only display the "compare with" for about 40 points, and "track control" for about 100 points. I also need to select them one by one as I wish to get data for all points. Is there any solution? Thank you very much!



Re: Re: Re: Re: Re: Data Export -
Douglas Brown Avatar
Douglas Brown
449 Posts

The only option I can think of is to track them in groups of less than 40 in separate tabs, then combine the data in Data Tool. When you double-click a Tracker plot comparing multiple tracks, all the data is transferred to Data Tool. To combine multiple tabs of data in Data Tool create a new editable tab, then copy from the other tabs with the transferred data and paste into the editable tab.

BTW I think this should work but I have never tried it with such a large number of data columns. Yours is a highly unusual situation! If it doesn't you may have to copy and paste your Tracker data into a spreadsheet.

> Hi! I am doing with more than 100 points. While a
> usual size monitor can only display the "compare with"
> for about 40 points, and "track control" for about
> 100 points. I also need to select them one by one
> as I wish to get data for all points. Is there any
> solution? Thank you very much!



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