Rescale position data within a viewr object

Should data have been exported at an incorrect scale, apply an isometric transformation to the position data and associated mean marker errors (if found)

Usage

rescale_tunnel_data(obj_name, original_scale = 0.5, desired_scale = 1, ...)

Arguments

obj_name

The input viewr object; a tibble or data.frame with attribute pathviewr_steps that includes "viewr" that has been passed through relabel_viewr_axes() and gather_tunnel_data() (or is structured as though it has been passed through those functions).

original_scale

The original scale at which data were exported. See Details if unknown.

desired_scale

The desired scale

...

Additional arguments passed to/from other pathviewr functions

Value

A viewr object that has position data (and mean_marker_error data, if found) adjusted by the ratio of desired_scale/original_scale.

Details

The desired_scale is divided by the original_scale to determine a scale_ratio internally. If the original_scale is not explicitly known, set it to 1 and then set desired_scale to be whatever scaling ratio you have in mind. E.g. setting original_scale to 1 and then desired_scale to 0.7 will multiply all position axis values by 0.7.

The default arguments of original_scale = 0.5 and desired_scale = 1 apply a doubling of tunnel size isometrically.

Author

Vikram B. Baliga

Examples

## Import the example Motive data included in the package
motive_data <-
  read_motive_csv(system.file("extdata", "pathviewr_motive_example_data.csv",
                             package = 'pathviewr'))

## Clean the file. It is generally recommended to clean up to the
## "gather" step before running rescale_tunnel_data().
 motive_gathered <-
   motive_data %>%
   relabel_viewr_axes() %>%
   gather_tunnel_data()

## Now rescale the tunnel data
motive_rescaled <-
  motive_gathered %>%
  rescale_tunnel_data(original_scale = 0.5,
                      desired_scale = 1)

## See the difference in data range e.g. for length
range(motive_rescaled$position_length)
#> [1] 0.07131 5.35294
range(motive_gathered$position_length)
#> [1] 0.035655 2.676470