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+PowerSAS.m
+==========
+
+**PowerSAS.m** is a robust, efficient and scalable power grid analysis
+framework based on semi-analytical solutions (SAS) technology. The
+**PowerSAS.m** is the version for MATLAB/Octave users. It currently
+provides the following functionalities (more coming soon!):
+
+-  **Steady-state analysis**, including power flow (PF), continuation
+   power flow (CPF), contingency analysis.
+-  **Dynamic security analysis**, including voltage stability analysis,
+   transient stability analysis, and flexible user-defined simulation.
+-  **Hybrid extended-term simulation** provides adaptive QSS-dynamic
+   hybrid simulation in extended term with high accuracy and efficiency.
+
+Key features
+~~~~~~~~~~~~
+
+-  **High numerical robustness.** Backed by the SAS approach, the
+   PowerSAS tool provides much better convergence than the tools using
+   traditional Newton-type algebraic equation solvers when solving
+   algebraic equations (AE)/ordinary differential equations
+   (ODE)/differential-algebraic equations(DAE).
+-  **Enhanced computational performance.** Due to the analytical nature,
+   PowerSAS provides model-adaptive high-accuracy approximation, which
+   brings significantly extended effective range and much larger steps
+   for steady-state/dynamic analysis. PowerSAS has been used to solve
+   large-scale system cases with 200,000+ buses.
+-  **Customizable and extensible.** PowerSAS supports flexible
+   customization of grid analysis scenarios, including complex event
+   sequences in extended simulation term.