A graphics-processor molecular-dynamics code stores a particle's velocity component…
PHYSICS · Multi-part · Fermi University Physics · Mathematical Methods for Physics · Numerical and computational mathematics · Numerical and computational mathematics
Error, Chance and the Machine, Ch Rounding, backward error and the sensitivity of a computation
Problem
A graphics-processor molecular-dynamics code stores a particle's velocity component v=−850.0ms−1 in the half-precision format, whose significand (including the implicit leading bit) has t=11 bits.
((a)) State ϵM and u for half precision.
((b)) Give the bound on the absolute error committed in storing v that follows from the rounding model fl(v)=v(1+δ), ∣δ∣≤u.