2021/01/04 by Kuszmaul, William
#Data Structures and Algorithms (cs.DS) #FOS: Computer and information sciences
paper · doi:10.48550/arxiv.2101.01108
Dynamic time warping distance (DTW) is a widely used distance measure between time series x, y ∈ Σn. It was shown by Abboud, Backurs, and Williams that in the binary case, where |Σ| = 2, DTW can be computed in time O(n1.87). We improve this running time O(n). Moreover, if x and y are run-length encoded, then there is an algorithm running in time O(k + ℓ), where k and ℓ are the number of runs in x and y, respectively. This improves on the previous best bound of O(kℓ) due to Dupont and Marteau.