# Index of Matlab Programs for Math 221

Written and Copyrighted by James Demmel, 1993, 1995
• Algorithm 1.1, bisect.m
• Question 1.20, polyplot.m
• Gaussian elimination without pivoting, genp.m
• Gaussian elimination with complete pivoting, gecp.m
• Program for generating Figures 2.1, 2.2, 2.3, 2.4 pivot.m (also needs gecp.m)
• Program for generating Figure 3.1, curvefitPLOT.m
• Program for Question 3.2, QRStability.m
• Image of unit circle under 2-by-2 matrix multiplication, illustrating SVD, svddemo2.m
• Image of unit circle under 3-by-3 matrix multiplication, illustrating SVD, svddemo3.m
• Plot real pseudospectrum, rpseudo.m
• Plot complex pseudospectrum, cpseudo.m
• Plot convergence of the Power method (Algorithm 4.1), powerplot.m
• Plot convergence of QR (or Orthogonal) iteration (Algorithms 4.4 and 4.3), used for Figures 4.2 and 4.3, qriter.m
• Plot real and complex pseudospectrum. Used for problem 4.4. eigscat.m
• Plot diagonal entries of a matrix undergoing unshifted QR iteration. Used for problem 4.5. qrplt.m
• Contour plot of Rayleigh quotient for any 3-by-3 symmetric matrix A. RayleighContour.m
• Illustrate cubic convergence of tridiagonal QR iteration. tridiQR.m