psi_equation_cpp: (C++) Equation of the Psi Dissimilarity Score

In distantia: Advanced Toolset for Efficient Time Series Dissimilarity Analysis

(C++) Equation of the Psi Dissimilarity Score

Description

Equation to compute the psi dissimilarity score (Birks and Gordon 1985). Psi is computed as \psi = (2a / b) - 1, where a is the sum of distances between the relevant samples of two time series, and b is the cumulative sum of distances between consecutive samples in the two time series. If a is computed with dynamic time warping, and diagonals are used in the computation of the least cost path, then one is added to the result of the equation above.

Usage

psi_equation_cpp(a, b, diagonal = TRUE)

Arguments

a	(required, numeric) output of cost_path_sum_cpp() on a least cost path.
b	(required, numeric) auto sum of both sequences, result of auto_sum_cpp().
diagonal	(optional, logical). Must be TRUE when diagonals are used in dynamic time warping and for lock-step distances. Default: FALSE.

Value

numeric

See Also

Other Rcpp_dissimilarity_analysis: psi_dtw_cpp(), psi_ls_cpp(), psi_null_dtw_cpp(), psi_null_ls_cpp()

distantia documentation built on April 4, 2025, 5:42 a.m.