# Overview¶

This document is a manual for $$K\omega$$ which is the library to solve the shifted linear equation within the Krylov subspace. This library provides routines to solve the following shifted linear equation (with the projection),

\begin{align} G_{i j}(z) = \langle i | (z {\hat I} -{\hat H})^{-1}| j \rangle \equiv {\boldsymbol \varphi}_i^{*} \cdot (z{\hat I}-{\hat H})^{-1} {\boldsymbol \varphi}_j. \end{align}

The source codes of $$K\omega$$ is written in FORTRAN and requires the BLAS Level 1 routines.

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Welcome to $$K\omega$$‘s documentation!

Algorithm