is the original interactive data reduction package developed for the Navy Precision Optical Interferometer at Lowell (NPOI). is an endeavor to combine all aspects of data reduction, modeling, astrometry, and imaging, including a stellar database, with an interactive data language in one package. Procedures are often shared. It also tries to maximize ease of use by providing both command line procedures and widget routines.
was created when three collections of scripts written first in PV-WAVE Command Language (PV-WAVE is a trademark of Rogue Wave Software) and then also in the Interactive Data Language (IDL is a trademark of Exelis Visual Information Solutions) were merged into one package for the purpose of providing a comprehensive data analysis package. The PV-WAVE version of is however no longer supported, while support for GDL (Gnu Data Language) has been added with version 8 of (no GUI support).
The three original collections, CHAMELEON which reduces a single night of NPOI data, AMOEBA which fits models to the calibrated visibility data of several nights, and STARBASE which implements a stellar data base and provides catalog access, are described in this User's Guide in separate parts. Also introduced are two new collections of scripts, COBRA, which provides functions for the interactive analysis of raw interferometry data (NPOI only), and PEARL, which images interferometry data.
As of 2014, has evolved into a package also supporting the reduction and analysis of data from interferometers other than NPOI. This includes the GUI front-ends MyMidiGui and MyAmberGui to the MIA+EWS (http://www.strw.leidenuniv.nl/nevec/MIDI/index.html) and amdlib (http://www.jmmc.fr/data_processing_amber.htm) data reduction softwares for MIDI and AMBER at VLTI, respectively. Also, observation planning and advanced data analysis is available in . Stand-alone reduction of data from other interferometers is not planned to be included in since this involves obviously very instrument specific tasks.
Data of other interferometers can be read and modeled by if they are stored using the OIFITS format (http://www.mrao.cam.ac.uk/research/OAS/oi_data/oifits.html).