Gene Golub and Charles Van Loan, Matrix Computations, C Johns Hopkins University Press, Baltimore, Maryland, C 1983. Made changes requested at July 1989 CML Meeting. Prologue converted to Version 4.0 format. Added complete declaration section. Corrected format of reference.
C C Look in all the lower triangle columns for a matching row.
C Scale the first column. Use the structure of A to pick out C the rows with something in column 1. N C C Update the IROW-th diagonal.