sage

14073859 -

gh-37175: search for a pair of pre- and post-isomorphism instead of just a post-isomorphism when computing dual isogeny While computing the dual of an isogeny, the current code only searches for a post-isomorphism which gives the correct scaling factor overall. In some cases, as shown by #37168, such an isomorphism may not exist, and we additionally have to compose with a suitable pre-isomorphism. This resolves #37168. URL: https://github.com/sagemath/sage/pull/37175 Reported by: Lorenz Panny Reviewer(s): Giacomo Pope, Lorenz Panny