mønstermatching

Mønstermatching is a Scandinavian term corresponding to the English "pattern matching" and refers to methods for recognizing, aligning, or extracting recurring structures in data. The concept spans multiple disciplines, including computer science, linguistics, cognitive psychology, textile and design, and bioinformatics. In everyday usage it denotes finding occurrences of a defined pattern within a larger dataset or environment.

In programming, mønstermatching commonly describes language features that decompose data structures by shape and content, as found in functional languages (for example, matching on tuples, lists, or algebraic data types). Regular expressions are a textual form of mønstermatching used for string search and transformation. In computer vision and image processing, mønstermatching involves locating visual templates or learned features in images. Graph and subgraph matching address structural correspondences in networks and molecules.

Algorithms and approaches vary by domain: linear-time string algorithms (Knuth–Morris–Pratt), multi-pattern search (Aho–Corasick), graph matching heuristics, and machine-learning models for pattern recognition. Complexity ranges from efficient polynomial-time solutions for many string and tree patterns to NP-hard problems such as general subgraph isomorphism.

Applications include parsing and compilers, data validation, search engines, object detection, pattern mining, and sequence alignment in biology. Related concepts include unification, template matching, motif discovery, and statistical pattern recognition.