generalized eigenfunction
21Finite difference — A finite difference is a mathematical expression of the form f(x + b) − f(x + a). If a finite difference is divided by b − a, one gets a difference quotient. The approximation of derivatives by finite differences… …
22Window function — For the term used in SQL statements, see Window function (SQL) In signal processing, a window function (also known as an apodization function or tapering function[1]) is a mathematical function that is zero valued outside of some chosen interval …
23Restricted Open-shell Hartree-Fock — (ROHF) is a variant of Hartree Fock theory for open shell molecules. It uses doubly occupied molecular orbitals as far as possible and then singly occupied orbitals for the unpaired electrons. This is the simple picture for open shell molecules… …
24Oscillation theory — In mathematics, in the field of ordinary differential equations, a non trivial solution to an ordinary differential equation is called oscillating if it has an infinite number of roots, otherwise it is called non oscillating. The differential… …
