matlab编程，计算速度能提高100倍慢的原因，是使用不对.doc

 HYPERLINK /loren  Loren on the Art of MATLAB March 1st, 2007  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \o Permanent Link to Creating Sparse Finite-Element Matrices in MATLAB  Creating Sparse Finite-Element Matrices in MATLAB  Im pleased to introduce Tim Davis as this weeks guest blogger. Tim is a professor at the University of Florida, and is the author or co-author of many of our sparse matrix functions (lu, chol, much of sparse backslash, ordering methods such as amd and colamd, and other functions such as etree and symbfact). He is also the author of a recent book,  HYPERLINK /SIAM/FA02.html Direct Methods for Sparse Linear Systems, published by SIAM, where more details of MATLAB sparse matrices are discussed (  HYPERLINK /%7Edavis /~davis ). Contents  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 1 MATLAB is Slow? Only If You Use It Incorrectly  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 2 How Not to Create a Finite-Element Matrix  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 3 Whats Wrong with It?  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 5 How MATLAB Stores Sparse Matrices  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 9 A Better Way to Create a Finite-Element Matrix  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 12 Moral: Do Not Abuse A(i,j)=... for Sparse A; Use sparse Instead  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 14 Try a Faster Sparse Function  HYPERLINK /loren/2007/03/01/creating-sparse-finite-element-matrices-in-matlab/ \l 15 When Fast is Not Fast Enough... MATLAB is Slow? Only If You Use It Incorrectly From time to time, I hear comments such as MATLAB is slow for large finite-element problems. When I look at the