{"id":894,"date":"2026-01-17T15:39:18","date_gmt":"2026-01-17T14:39:18","guid":{"rendered":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/2026\/01\/17\/la-constante\/"},"modified":"2026-01-17T18:01:41","modified_gmt":"2026-01-17T17:01:41","slug":"la-constante","status":"publish","type":"post","link":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/la-constante\/","title":{"rendered":"La constante"},"content":{"rendered":"

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Extrait du code source du moteur d\u2019\u00e9checs Stockfish, fichier position.cpp.
Disponible sur : https:\/\/github.com\/official-stockfish\/Stockfish<\/a> [GNU General Public License].<\/p>\n

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\u00c0 propos du code<\/strong><\/h1>\n

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Les programmes informatiques sont des objets vivants, en perp\u00e9tuelle \u00e9volution. De nouvelles fonctions apparaissent, les algorithmes s\u2019affinent, les param\u00e8tres se r\u00e8glent. Pourtant, une constante \u2013 1070372 \u2013 demeure inchang\u00e9e depuis 2014 dans le code source de Stockfish, l\u2019un des plus puissants moteurs d\u2019\u00e9checs open source jamais cr\u00e9\u00e9s. <\/p>\n

1070372 sert de graine : un nombre initial qui aide \u00e0 g\u00e9n\u00e9rer les \u00ab empreintes \u00bb des positions d\u2019\u00e9checs. Ces empreintes permettent au programme de reconna\u00eetre les positions d\u00e9j\u00e0 analys\u00e9es, gagnant du temps et \u00e9vitant les recalculs inutiles. Dans toute l\u2019histoire de Stockfish, 1070372 est la plus ancienne valeur enti\u00e8re rest\u00e9e intacte. Les contributeurs ont essay\u00e9 d\u2019autres nombres, mais ont toujours fini par revenir \u00e0 cette constante d\u2019origine. Contributors have experimented with different values, eventually always going back to the original constant.<\/p>\n

Dans un syst\u00e8me en \u00e9volution permanente, un point fixe rend les progr\u00e8s mesurables : si tout change en m\u00eame temps, il devient impossible de savoir ce qui aide ou nuit. En gardant une valeur stable, les d\u00e9veloppeurs peuvent exp\u00e9rimenter sans risque sur le reste, et reproduire les r\u00e9sultats d\u2019un ordinateur ou d\u2019une version \u00e0 l\u2019autre, prouvant que les gains viennent de vraies innovations, non du hasard.
Le choix de 1070372 n\u2019a rien d\u2019arbitraire ou de mystique : il r\u00e9sulte d\u2019un raisonnement rigoureux, de tests statistiques et de discussions ouvertes entre contributeurs. Dans un projet collaboratif comme Stockfish, les d\u00e9cisions se prennent de mani\u00e8re transparente, et cette constante en est l\u2019illustration. <\/p>\n

Pour paraphraser Donald Knuth, l\u2019histoire des moteurs d\u2019\u00e9checs est celle du triomphe de l\u2019ing\u00e9nierie logicielle m\u00eal\u00e9e \u00e0 de magnifiques math\u00e9matiques. La constante 1070372 en est le symbole : un petit nombre ancrant une immense base de code en mouvement, aidant \u00e0 transformer le chaos en compr\u00e9hension \u2013 et la compr\u00e9hension en intelligence \u00e9chiqu\u00e9enne surhumaine. <\/p>\n

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BIOGRAPHIE<\/strong><\/h1>\n

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Mathieu Acher <\/strong>est professeur d\u2019informatique \u00e0 l\u2019INSA Rennes, o\u00f9 ses recherches portent sur l\u2019\u00e9volution et la variabilit\u00e9 des syst\u00e8mes logiciels, \u00e0 l\u2019intersection du g\u00e9- nie logiciel et de l\u2019intelligence artificielle. Il est \u00e9galement ma\u00eetre FIDE \u2013 un titre officiel d\u00e9cern\u00e9 par la F\u00e9d\u00e9ration internationale des \u00e9checs. Joueur d\u2019\u00e9checs depuis toujours, il entretient un lien fort avec Stockfish, l\u2019un des moteurs d\u2019\u00e9checs open source les plus puissants au monde. <\/p>\n

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#Chess<\/strong><\/p>\n

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#Open-Source<\/strong><\/p>\n

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#Ing\u00e9nierie logicielle<\/strong><\/p>\n

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Extrait du code source du moteur d\u2019\u00e9checs Stockfish, fichier position.cpp.Disponible sur : https:\/\/github.com\/official-stockfish\/Stockfish [GNU General Public License].\u00c0 propos du codeLes programmes informatiques sont des objets vivants, en perp\u00e9tuelle \u00e9volution. De nouvelles fonctions apparaissent, les algorithmes s\u2019affinent, les param\u00e8tres se r\u00e8glent. Pourtant, une constante \u2013 1070372 \u2013 demeure inchang\u00e9e depuis 2014 dans le code source de […]<\/p>\n","protected":false},"author":4,"featured_media":893,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[108],"tags":[121,123,122],"class_list":["post-894","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-miroir-de-la-societe","tag-echecs","tag-ingenierie-logicielle","tag-open-source"],"_links":{"self":[{"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/posts\/894","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/comments?post=894"}],"version-history":[{"count":7,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/posts\/894\/revisions"}],"predecessor-version":[{"id":903,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/posts\/894\/revisions\/903"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/media\/893"}],"wp:attachment":[{"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/media?parent=894"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/categories?post=894"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sourcecode-exhibition.softwareheritage.org\/fr\/wp-json\/wp\/v2\/tags?post=894"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}