## Version 1.0.0

It identiﬁes which equations are ignored when solving $Ax=b$ and which solution components are always set to zero. The roles are reversed for ${A}^{T}x=b$. There are such equations and/or components in the singular or rectangular case. Note that if $Ax=b$ or ${A}^{T}x=b$ is not consistent, there may be large residuals for the equations that are ignored.