http://www.mapleprimes.com/questions/40613-Matrix-Computation en-us 2026 Maplesoft, A Division of Waterloo Maple Inc. Maplesoft Document System Sat, 13 Jun 2026 02:10:27 GMT Sat, 13 Jun 2026 02:10:27 GMT The latest answers and comments added to the Question, matrix computation http://www.mapleprimes.com/images/mapleprimeswhite.jpg http://www.mapleprimes.com/questions/40613-Matrix-Computation http://www.mapleprimes.com/questions/40613-Matrix-Computation?ref=Feed:MaplePrimes:matrix computation:Comments#answer75061 Your final do-loop assigns columns, in-place, into what you intend to be Matrix P. But you haven't created the Matrix P, yet. Try adding, P := Matrix(3,3): before that final do-loop. You might also think that P should be purely real. You could try simplify(map(fnormal,P)) at the end. But maybe you would rather compute the eigenvectors of a floating-point symmetric version of stif2, instead of doing floating-point evaluation of the eigenvectors of the exact stif2? Ie,, Eigenvectors(evalf(Matrix(stif2,shape=symmetric))); acer Your final do-loop assigns columns, in-place, into what you intend to be Matrix P. But you haven't created the Matrix P, yet. Try adding, P := Matrix(3,3): before that final do-loop. You might also think that P should be purely real. You could try simplify(map(fnormal,P)) at the end. But maybe you would rather compute the eigenvectors of a floating-point symmetric version of stif2, instead of doing floating-point evaluation of the eigenvectors of the exact stif2? Ie,, Eigenvectors(evalf(Matrix(stif2,shape=symmetric))); acer 75061 Mon, 29 Oct 2007 21:02:05 Z acer acer