Editing IDL (programming language) (section)

==History==
{{original research|section|date=September 2015}}
The predecessor versions of IDL were developed in the 1970s at the [[Laboratory for Atmospheric and Space Physics]] (LASP) at the [[University of Colorado at Boulder]]. At LASP, David Stern was involved in efforts to allow scientists to test hypotheses without employing programmers to write or modify individual applications. The first program in the evolutionary chain to IDL that  Stern developed was named Rufus; it was a simple vector-oriented calculator that ran on the [[PDP-12]]. It accepted two-letter codes that specified an arithmetic operation, the input registers to serve as operands, and the destination register. A version of Rufus developed on the [[PDP-8]] was the Mars Mariner Spectrum Editor (MMED). MMED was used by LASP scientists to interpret data from [[Mariner 7]] and [[Mariner 9]]. Later, Stern wrote a program named SOL, which also ran on the PDP-8. Unlike its predecessors, it was a true programming language with a FORTRAN-like syntax. SOL was an array-oriented language with some primitive graphics capabilities.<ref name="idl_faq">{{cite web |last1=Schienle |first1=Mike |title=IDL FAQ |url=http://www.faculty.virginia.edu/rwoclass/astr511/IDLresources/idl-faq-ivsoft-v4.html |access-date=8 February 2019 |date=1991-01-19}}</ref>

Stern left LASP to found Research Systems Inc. (RSI) in 1977. The first RSI product was IDL for the PDP-11.<ref name ="idl_faq"/> In this release, the graphics supported by IDL were primarily Tektronix terminals and raster graphics displays. RSI sold its first IDL licenses to NASA's [[Goddard Space Flight Center]] and [[Ball Aerospace & Technologies Corp.]] in 1979. Two years later RSI released an initial VAX/VMS version of IDL, which was written in [[VAX MACRO]] and FORTRAN. It took advantage of the VAX virtual memory and 32-bit address space.<ref name ="idl_faq"/> The [[National Center for Atmospheric Research]] (NCAR), the [[University of Michigan]], the [[University of Colorado at Boulder|University of Colorado]], and the [[Naval Research Laboratory]] started to use IDL with this version.

In 1987 RSI shifted development work of IDL to the [[Unix]] environment, which required a complete re-write of the code in C rather than a port of the existing version of VAX IDL. <ref name ="idl_faq"/> Stern and Ali Bahrami rewrote IDL for Unix on the Sun 3, taking advantage of the re-write to extend and improve the language. Subsequently, IDL was further expanded and ported to several variants of Unix, VMS, Linux, Microsoft Windows (1992), and Mac OS (1994).

Widgets were added to IDL in 1992, providing [[event-driven programming]] with [[graphical user interface]]s. In 1997 ION (IDL On the Net), a web server-based system, was commercially released. The first version of [[ENVI (software)|ENVI]], an application for [[remote sensing]] [[multispectral]] and [[hyperspectral]] image analysis written in IDL, was released in 1994. [[ENVI (software)|ENVI]] was created, developed and owned by Better Solutions Consulting, LLC, until it was purchased from BSC in October 2000 by Eastman Kodak coincident with their purchase of RSI.  RSI sold, marketed and supported [[ENVI (software)|ENVI]] under the terms of a license agreement with BSC, LLC from 1994 through October 2000.   New object and pointer types, and limited [[object-oriented programming]] capabilities, were added to IDL in 1997.

IDL has been applied widely in space science, for example in [[solarsoft|solar physics]]. The [[European Space Agency]] used IDL to process almost all of the pictures of [[Halley's Comet]] taken by the [[Giotto (spacecraft)|Giotto]] spacecraft. The team repairing the [[Hubble Space Telescope]] used IDL to help them diagnose anomalies in the main mirror. In 1995, astronauts on board a [[Space Shuttle]] used IDL loaded on a laptop to study ultraviolet radiation. Currently, amongst other applications, IDL is being used for most of the analysis of the SECCHI part of the [[STEREO]] mission at [[United States Naval Research Laboratory|NRL]], USA, and at the Rutherford Appleton Laboratory, UK.

RSI became a wholly owned subsidiary of [[ITT Industries]] in March 2004. As of 15 May 2006, RSI began doing business as [[ITT Visual Information Solutions]]. Effective 31 October 2011, as a result of restructuring, that company became [[Exelis Visual Information Solutions]].  In 2015, IDL was purchased by [[Harris Geospatial|Harris Geospatial Solutions]] which later became [[L3Harris Geospatial|L3Harris Geospatial Solutions]]. In April 2023, IDL was acquired by [https://www.nv5geospatialsoftware.com/Products/IDL NV5 Geospatial].