Power Quality surveys and studies show that the major part of end users has limited knowledge on power quality and its possible impact on equipment and installation. Even when power quality monitoring systems are in place, end users have difficulties to follow, understand, analyze and exploit power quality measurements. The purpose of this paper is to introduce simple green-yellow-red indicators for each power quality problem. Easy to understand and integrate in a power quality monitoring system, they are based on recognized power quality standards and statistical analysis. This paper introduces as well a Power Quality Index, summarizing the global power quality level.

III this paper we present. our irnpl~~~~e1itation of aut.omatic~ differcntiat.ion (ie. differc!I~tiilt.ioIl of functions Icprf:scut.c:d by programs) in Mnylc: it fidly supports the rcwrsc mode illld eut.ends diffcrent.iat.ion to cqw with commou linear-algebra operators. It. aIs ndws use of standard fcaturcs of CAS t.0 tlctermine c0nflic~t.s~ optimize computation scc4uenccs and IIlenrOry i~lh:iltiOn.