POCKET ARITHMETIC AND NEEDLEMAN-WUNSCH ON CRAY RESEARCH COMPUTERS

Autor: David J. Anderson, Sr. Sales Analyst, James H. Fry, Eugene D. Fleischmann
Rok vydání: 1993
Předmět:
Zdroj: Bioinformatics, Supercomputing and Complex Genome Analysis.
DOI: 10.1142/9789814503655_0036
Popis: In the interest of providing more efficient computer-based analysis of DNA and protein sequences, Cray Research has developed a high performance implementation of the sequence alignment method of Needleman and Wunsch using the programming technique of pocket arithmetic. The basis for this implementation is the program SEQHDP, which finds locally homologous subsequences of a protein sequence pair and determines the statistical significance of the homology. Pocket arithmetic takes advantage of the 64-bit width of an operand on the Cray Y-MP by packing more than one integer value per word, then performing logical or integer operations on the packed word to yield multiple results per operation. This technique, in combination with the vector processing capabilities of the Cray Y-MP CPU, produces substantially improved performance over the conventionally coded version of the same algorithm. The authors will introduce the programming technique of pocket arithmetic, then describe its implementation in the Needleman-Wunsch sequence comparison function in SEQHDP. Performance results based on actual protein sequence comparisons are presented.
Databáze: OpenAIRE