HSL (Fortran library)

<h2 id="history">History</h2>
<h3>Early history</h3>
<p>Original development of the Harwell Subroutine Library began in 1963 by Mike Powell and Mike Hopper for internal use on an IBM mainframe at <a href="/facts/Atomic_Energy_Research_Establishment/4UMoNfcP">AERE Harwell</a>. Early contributors also included Alan Curtis. With a spreading reputation, the Library was distributed externally for the first time in 1964 upon request.  The first library catalog (AERE Report M-1748) was released in 1966.
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<h3>Recent history</h3>
<p>Over the intervening years, HSL has striven to maintain a high standard of reliability and has garnered a worldwide reputation as a prime source of numerical software. It has undergone a number of changes to reflect newly available features of the Fortran language, completing in 1990 the conversion to Fortran 77, and more recently, the entire Library has been made <a href="/facts/Thread_safe/fx3ULqUw">thread safe</a>. Many newer codes are written in Fortran 95.
</p><p>New packages continue to be developed, with a new release issued every two to three years. Many older codes have now been superseded and are available in the HSL Archive.
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<h2 id="licensing">Licensing</h2>
<p>The current version, <i>HSL 2007</i> is a commercial product sold by <a href="/facts/Aspen_Technology/lkrmrs7G">AspenTech</a>, but is also available without charge to individual academics direct from STFC for teaching and their own academic research purposes.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> HSL is currently not sold to commercial competitors of Aspen Technology.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a>
</p><p>Obsolete routines are stored in the <i>HSL archive</i> and are available for personal non-commercial use by anyone following registration with HSL. Commercial use and distribution of these routines still requires a purchased licence.<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a>
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<ul><li>J.K.Reid and J.A.Scott (Dec 2006, Sep 2007), <i>Guidelines for the development of HSL software</i>, Technical Report <a href="ftp://ftp.numerical.rl.ac.uk/pub/reports/rsRAL2006031.pdf">RAL-TR-2006-031</a></li>
<li>M.J.D.Powell <i>25 years of Theoretical Physics 1954-1979: Chapter XVIII: Numerical Analysis</i>. A special publication by Harwell Research Laboratory of UKAEA</li></ul>
<h2 id="footnotes">Footnotes</h2>

<h2 id="external-links">External links</h2>
<ul><li><a href="http://www.hsl.rl.ac.uk/">HSL home page at STFC</a></li>
<li><a href="https://web.archive.org/web/20080325071113/http://www.aspentech.com/hsl/">HSL home page at AspenTech</a></li>
<li><a href="http://hsl.rl.ac.uk/archive/hslarchive.html">HSL Archive</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>"The HSL Mathematical Software Library". STFC. Retrieved 2010-07-05. <a href="http://www.hsl.rl.ac.uk/" target="_blank">http://www.hsl.rl.ac.uk/</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>"HSL60 a brief history of the HSL mathematical software library" (PDF). STFC. Retrieved 2023-05-05. <a href="https://epubs.stfc.ac.uk/manifestation/54066721/STFC-TR-2023-002.pdf" target="_blank">https://epubs.stfc.ac.uk/manifestation/54066721/STFC-TR-2023-002.pdf</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>"HSL archive". STFC. Retrieved 2010-07-05. <a href="http://www.hsl.rl.ac.uk/archive/hslarchive.html" target="_blank">http://www.hsl.rl.ac.uk/archive/hslarchive.html</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
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HSL (Fortran library) open-in-new

HSL (Fortran library)