Rework grouping code to compare distances with a custom accuracy. Disabled by default (accuracy=0.0), may be changed by setting HWLOC_DISTANCES_ACCURACY=0.02 in the environment.
Rework grouping code to compare distances with a custom accuracy.
Disabled by default (accuracy=0.0), may be changed by setting
HWLOC_DISTANCES_ACCURACY=0.02 in the environment.

0.02 seems to help when the user provides a measurement-based latency matrix
(on quad-socket octo-core nehalem-ex machine).

Refs: #43

git-svn-id: 8218ceca4dcdaeae1c916fd7b158ab3fcd61422a@3545 4b44e086-7f34-40ce-a3bd-00e031736276

BlueBrain/hwloc,BlueBrain/hwloc,BlueBrain/hwloc,BlueBrain/hwloc