Knowledge Base

Narrow (or Too Thick) Track Lines

Solution: In various parts of EthoVision XT you can change the thickness of the lines and the size of the dots.

1. Click Show/Hide (at the top-right corner of the screen) and select Detection Features.
2. Adjust the Line thickness and Dot size.

Note:

• What you select in the Detection Settings screen are also selected in the Acquisition screen, and the other way round.
• What you select in one of the following screens is also selected in the other screens: Track Editor, Track Visualization, Integrated Visualization, Manual Scoring screen.
• The line thickness is also applied to the body contour in Detection Settings and Acquisition screen. It is not available in the Manual Scoring screen.

Some Values Show as 0.5

This is due to the type of resampling selected in the external variable of your Analysis profile. Consider the following example. The first plot shows the original signal imported from UltraVox XT and the second plot shows the same signal after resampling.

For the second call at 25.5, the time between the "1" and "0" in the original signal is so short that it fits in one sample interval.

Two points in the same sample interval result in downsampling. Open the Analysis profile, and open the External data variable. See External data (resampled).

• If you choose Mean for downsampling, the value A in the resampled signal will be the average of 1 and 0, that is 0.5.
• If you choose Total for downsampling, the value in the resampled signal will be 1 + 0 = 1. After selecting Total, the signal is corrected.

So, choosing Total should solve the issue.

The Integrated Visualization Shows "Not Calculated"

One or more trials are corrupt, or something went wrong with editing the tracks. See The Results Table Contains "?" in Many Cells.

The Data Preparation Report Says "Failed" for Some Trials

This message occurs in experiments with Deep learning based body point detection. In some cases EthoVision XT fails to review the tracks and fix subject identity swaps. For example, when the two subjects spent most of the trial time in close contact. See the note in Prepare the Data in Multi-Subject Trials.

I Cannot Visualize a Trial

In most cases, this occurs when a Data profile is active that does not include that trial. Make a Data profile that includes that trial and visualize the data. See Filter Tracks.

The Name of the Trial Is Not Fully Visible

The name of the trial on the toolbar of the Integrated Visualization screen is partially hidden. This may occur when the display is set to a high resolution. Reduce the screen resolution in Windows.

Heatmap Color Smoothing Across Other Arenas

Solution: In the Heatmap Settings pane, click Colors and under Smoothing select a lower value.

See also:

• Color smoothing

Group Mean Button Not Available

You are probably working with a DanioVision experiment. The Group Mean button is disabled in experiments set as DanioVision.

How Can I Merge Heatmaps Generated in Different Arenas?

For example, you acquired tracks in Arena 1 and Arena 3 with subjects that belong to the same treatment group, and you would like to create one heatmap based on the data of both arenas.

Unfortunately, merging heatmaps from different arenas is not possible within EthoVision XT. However, with simple JavaScript code you can re-calculate the coordinates in the tracks and export them to an external application that creates heatmaps. The following describes a possible solution:

1. In the Arena Settings, define a Point of interest (see Draw a Point) in each arena. For example, the south-west corner of the open field. This point will be the new reference point of the coordinates, so it must represent the same physical location in all arenas.

   If the arenas already include a zone or point, like the shelter of PhenoTyper, and the zone has the same position and orientation in all arenas, then you do not need to define a Point of interest.

2. In the Analysis profile, add two JavaScript continuous variables. See JavaScript Continuous.

   The first variable is for recalculating the x-coordinate. Add the following text (replace "Point" with the name of your point or zone):

   const g_zone = "Point";
   function Start()
   {
   }
   function Stop()
   {
   }
   function Process()
   {
       var pt1 = GetCenter();
       var pt2 = GetPointPoi(g_zone);
       if (pt1)
       {
           var xc = pt1.x - pt2.x;
           SetOutput(xc);
       }
       else
       {
           SetOutputMissing();
       }
   }

3. For the second variable, repeat the step above, this time replacing x with y.
4. Export the two variables (Analysis > Export > Raw Data). These contain the x,y coordinates expressed relative to the point in the arena.
5. Import the data in an application that creates heatmaps, such as Excel Power Maps, R, or MATLAB.

Source: EthoVision XT 19 Help, Noldus Information Technology