flyrun: Track speed calculator
In PaolaCognigni/CTraxHelper: CTrax Helper
Description
Usage
Arguments
Details
Value
Description
Calculates the speed (scalar) in px/frame by comparing centroid location across framelag.
Usage
1
flyrun(trx, framelag = 6)
Arguments
trx
a track data frame (only requires CTrax output variables)
framelag
the number of frames to derive speed across; defaults to 6
Details
For each timepoint t the velocity vector is calculated between t-framelag/2 and t+framelag+2.
Currently this leaves framelag/2 NAs at the beginning and end of each track. This causes all sorts of problems
and may be best addressed somehow in the future.
Frames with speed>50 are also currently NA'd since that is exclusively artifacts (CTrax already limits jumps to 40 px/frame)
however this again causes holes in the data which become problematic later. Ideally the imputation would be done at the x and y level.
Value
A numeric vector matching the structure of trx containing the speed value for each object and timepoint, or NAs when it can't be calculated.
PaolaCognigni/CTraxHelper documentation built on May 7, 2019, 11:57 p.m.
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Description Usage Arguments Details Value
Description
Calculates the speed (scalar) in px/frame by comparing centroid location across framelag.
Usage
1 | flyrun(trx, framelag = 6)
|
Arguments
trx |
a track data frame (only requires CTrax output variables) |
framelag |
the number of frames to derive speed across; defaults to 6 |
Details
For each timepoint t the velocity vector is calculated between t-framelag/2 and t+framelag+2.
Currently this leaves framelag/2 NAs at the beginning and end of each track. This causes all sorts of problems
and may be best addressed somehow in the future.
Frames with speed>50 are also currently NA'd since that is exclusively artifacts (CTrax already limits jumps to 40 px/frame)
however this again causes holes in the data which become problematic later. Ideally the imputation would be done at the x and y level.
Value
A numeric vector matching the structure of trx containing the speed value for each object and timepoint, or NAs when it can't be calculated.
R Package Documentation
Browse R Packages
We want your feedback!
Note that we can't provide technical support on individual packages. You should contact the package authors for that.
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