He also helped devise the Weierstrass–Erdmann condition, which gives sufficient conditions for an extremal to have a corner along a given extrema, and allows one to find a minimizing curve for a given integral.
Karl Weierstrass | Exhibit B: The Human Condition | Erdmann August of Brandenburg-Bayreuth | condition | Association for Improving the Condition of the Poor | race condition | Papa's Delicate Condition | Lost Planet: Extreme Condition | human condition | Weierstrass theorem | Weierstrass–Erdmann condition | Rear entrance to Nana Phadanvis' house (''Nana phadanvis wada'') which is still preserved today in the same condition as when Nana built it in 1780. Location: Menawali | Mint Condition | Mint condition | Lindemann–Weierstrass theorem | Human condition | Force Protection Condition | Condition |
Other valuable treatises and memoirs have been written by Strauch (1849), Jellett (1850), Otto Hesse (1857), Alfred Clebsch (1858), and Carll (1885), but perhaps the most important work of the century is that of Weierstrass.
Cantor biographer Joseph Dauben argues that "local circumstances" refers to the influence of Leopold Kronecker, Weierstrass' colleague at the University of Berlin.
After qualifying as a teacher of mathematics and physics Vályi was awarded a scholarship to allow him to study for two years at the University of Berlin, where the remarkable mathematics team of Kummer, Borchardt, Weierstrass and Kronecker were lecturing.
After Weierstrass and Runge, many mathematicians (in particular Walsh, Keldysh, and Lavrentyev) had been working on the same problem.
Under the influence of Weierstrass and Bernhard Riemann this concept and related questions were intensely studied at the end of the 19th century by Hermann Hankel, Paul du Bois-Reymond, Ulisse Dini, Cesare Arzelà and others.