NHSE Software Catalog

V_SQRT - A Library Routine for Computing Square Roots of Double-Precision Vectors on CRAY MPP

url

ftp://sdcd.gsfc.nasa.gov/pub/HPCC/ESS/udaya/v_sqrt.tar.Z

abstract

Computing square-roots have a substantially high result latency on the Cray
MPP. We have implemented an efficient software routine on Cray MPP to
compute the square-roots of a double-precision real vector. This program
written in CAM assembler language runs about seven times faster than the
currently available library routine. The worst case deviation of the computed
values using v_sqrt from those computed using the standard library routine is
about one least significant bit.

description

http://sdcd.gsfc.nasa.gov/ESS/exchange/contrib/udaya/v_sqrt.html

contact

Udaya A. Ranawake / udaya@neumann.gsfc.nasa.gov

keywords

square root computation; numerical routine; architecture dependence

environment

Cray MPP, written in CAM assembler language