Source: wikibot/schwarz-function
= Schwarz function
{wiki=Schwarz_function}
A Schwarz function, also known as a "test function" in the context of distribution theory, is a smooth function that rapidly decreases at infinity along with all its derivatives. More formally, a function \\( f: \\mathbb\{R\}^n \\to \\mathbb\{R\} \\) is called a Schwarz function if it satisfies the following conditions: 1. \\( f \\) is infinitely differentiable (i.e., \\( f \\in C^\\infty \\)).