circhelp

circhelp is a small helper package for circular data analyses in R, particularly useful for cognitive studies on orientation, motion direction, and other circular features. The package contains functions for descriptive statistics for circular data (computing means, SD, and skewness), angular differences, and correlation. It also includes a function to correct for cardinal biases in the human estimates of circular features (e.g., orientation).

Installation

You can install the current version from GitHub with:

# install.packages("devtools")
devtools::install_github("achetverikov/circhelp")

Usage

Most functions are self-explanatory.

library(circhelp)
#> Loading required package: data.table
#> Loading required package: ggplot2

library(mgcv)
#> Loading required package: nlme
#> This is mgcv 1.9-1. For overview type 'help("mgcv-package")'.

# compute a set of descriptive statistics
x <- rnorm(500)
circ_descr(x)
#> $mu
#> [1] 0.07084994
#> 
#> $sigma
#> [1] 0.9691056
#> 
#> $skew_pewsey
#> [1] 0.0118935
#> 
#> $skew_fischer
#> [1] -0.04671673
#> 
#> $rho
#> [1] 0.6252631
#> 
#> $skew_rel_to_zero
#> [1] 0.03426532

# compute difference in orientations
a <- 5
b <- 170
angle_diff_180(a, b)
#> [1] 15

# compute difference in 360° space (e.g., motion directions)
angle_diff_360(a, b)
#> [1] -165

# compute correlation between angles
data <- rmvn(10000, c(0, 0), V = matrix(c(1, 0.5, 0.5, 1), ncol = 2))
circ_corr(data[, 1], data[, 2])
#> [1] 0.4392524

The only (somewhat) complicated function is remove_cardinal_biases, see the help files and the vignette for an example use case.