# System variables

To view/hide a system variable

1.From the Show/Hide menu on the toolbar, choose Variables.

2.Select the variables you want to view.

To hide a system variable, clear its check box.

System variables

Acquisition status

The current status per arena:

▪Planned. When a trial is added to the Trial List, all the arenas within the trial get the status Planned.

▪To Skip. You can give an arena the status To skip when for any reason you do not want or cannot track a subject in that arena. For example, when the subject that was planned in that arena is no longer available.

▪Skipped. The status Skipped is given to an arena that was previously set to To skip. The status Skipped is therefore a label given after the trial has been acquired (or at least video was recorded for that trial). See also Skip arenas within a trial.

▪Postponed. This label appears when you choose to record video and track later (see Record video, then acquire a trial). After recording video, the arenas within a trial get the status Postponed. After you do tracking from that video, the status changes to Acquired.

▪Postponed To Skip. If you have recorded video without tracking the status of the trials/arenas in the Trial List is Postponed (see above). Now you can choose to skip one of the trials/arenas by selecting Postponed to Skip. Do this for example if one of the arenas in the video is empty.

▪Waiting. An arena gets the status Waiting when you have started the trial but acquisition did not yet start because you defined a Trial Control profile with a Start recording rule and the starting condition is not yet met.

▪Acquiring. An arena gets the status Acquiring when acquisition is ongoing.

▪Acquired. An arena gets the status Acquired when data has been acquired for that arena.

Arena name

The name of the Arena in which the animal was tracked.

Arena Settings

The name of the Arena Settings used to acquire your tracks.

Detection settings

The name of the Detection Settings used to acquire your tracks.

Interpolated samples

The proportion of samples that were interpolated during the trial, expressed in percentage. Interpolation occurs when the camera fails to send the video frames at the expected time. For details, see in Detection settings: Advanced setup > Dropped frames correction.

Missed Samples

The proportion of missed samples, expressed in percentage. EthoVision misses samples if the processor load is too high or the camera delivers fewer video frames than expected. See also Missed samples

Recording after

The length of the interval between the start of the trial and the start of acquisition. This variable has the value 0 unless you defined a condition between the Start trial box and the Start track box in the Start-stop trial rule in the Trial Control settings.

Recording duration

The length of the interval from start of acquisition till stop of acquisition. Recording duration is equal to Trial duration unless you defined a condition between the Start trial box and the Start track box in the Start-stop trial rule in the Trial Control settings.

Start time

The date/time of the start of the trial.

Subject name

The name of the subject that track refers to. Subject names are specified in the Experiment Settings.

Subject not found

Proportion of time the subject was not found. If the subject is not found, it means EthoVision processed the sample but did not find anything matching the current Detection Settings. Therefore, this system variable is a measure of the quality of detection.

Sync status

The status of the sync-out file. When no external data co-acquisition has been carried out for a specific trial, the status is Planned. As soon as co-acquisition is started on the DAQ system, the status becomes Acquired.

Track

The name of the track file.

Tracking source

The video input on the encoder board connected to the camera. If you use a digital camera, this is the name of the camera. The cell is empty when you track from a video file.

Trial Control settings

The name of the Trial Control profile used during tracking.

Trial Duration

The length of the interval from start of the trial until the stop of the trial.

Trial name

By default, Trial 1, Trial 2, etc. To change a trial name, double-click it and enter a new name.

Video file

The name and location of the video file that was used or will be used for acquisition.

Video start time

The date and time the video file that you used for tracking, was created.

System variable format

For the Time stamp variables (Start time and Video start time) and Duration variables (Recording after, Recording duration and Trial Duration) you can specify the format.

Double-click in the Format field. In the Format string window, enter your preferred format in the field at the top and click OK.

For the other system variables Label, Description, Type, Predefined Values and Scope you cannot change their format.

See also

▪The default Start-Stop Trial rule