Update README.md

Author: caesarcai

README.md

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 # AccAltProj for RPCA
 This is the Matlab code repo for a fast provable non-convex Robust Principal Component Analysis (RPCA) algorithm introduced in [1], which has theoretical global linear convergence guarantee and high robustness in practice. 
 
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 ## Robust Principal Component Analysis
 In this project, we focus on RPCA problem under fully observed setting, that is about separating a low rank matrix $L\in \mathbb{R}^{m\times n}$ and a sparse outlier matrix $S\in \mathbb{R}^{m\times n}$ from their sum $D = L + S$.