Like Bolzano, Karl Weierstrass denied continuity of a function at a point c unless it was defined at and on both sides of c, but Édouard Goursat allowed the function to be defined only at and on one side of c, and Camille Jordan allowed it even if the function was defined only at c.
Como Bolzano, Karl Weierstrass negou a continuidade dunha función nun punto c a menos que estivese definida a ambos os lados de c, mais Édouard Goursat permitía que unha función estivese definida só nun lado de c, e Camille Jordan incluso se a función estaba definida só no punto c.