** Orthogonal-triangular decomposition. **

** [Q,R] = QR(X) produces an upper triangular matrix R of **

** the same dimension as X and a unitary matrix Q so that **

** X = Q*R. **

** [Q,R,E] = QR(X) produces a permutation matrix E , an **

** upper triangular R with decreasing diagonal elements and **

** a unitary Q so that X*E = Q*R. **

** By itself, QR(X) returns the output of LINPACK'S ZQRDC **

** routine. TRIU (QR(X)) is R. **

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** See also QRDELETE , QRINSERT . **

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