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Data Export - Nov 11, 2012 at 11:17AM
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 - Nov 11 2012 1:39PM
Douglas Brown Avatar
Douglas Brown
94 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 - Jan 16 11:36AM
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 - Jan 16 12:02PM
Douglas Brown Avatar
Douglas Brown
94 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



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