bookmark Triplex Searches and visualizes intramolecular triplex-forming sequences in DNA. triplex provides functions for identification and visualization of potential intramolecular triplex patterns in DNA sequence. The main functionality is to detect the positions of subsequences capable of folding into an intramolecular triplex (H-DNA) in a much larger sequence. Functions producing 2D and 3D diagrams of the identified triplexes allow instant visualization of the search results. In connection with R language and existing libraries for statistical analysis, the package represents powerful tool for molecular biologists interested in analysis of non-canonical DNA structures such as triplexes.