Matrix: Davis/FX_March2010

Description: MATLAB FileExchange, keyword analysis (March 2010)

Davis/FX_March2010 graph
(bipartite graph drawing)

Davis/FX_March2010 dmperm of Davis/FX_March2010
scc of Davis/FX_March2010

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  • download as a MATLAB mat-file, file size: 722 KB. Use UFget(2568) or UFget('Davis/FX_March2010') in MATLAB.
  • download in Matrix Market format, file size: 933 KB.
  • download in Rutherford/Boeing format, file size: 693 KB.

    Matrix properties
    number of rows1,319
    number of columns9,498
    structural full rank?no
    structural rank1,140
    # of blocks from dmperm72
    # strongly connected comp.163
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorT. Davis
    editorT. Davis
    kindterm/document graph
    2D/3D problem?no

    Additional fieldssize and type
    keycell 1319-by-1
    idfull 9498-by-1
    inbookfull 1-by-1


    Analysis of the MATLAB FileExchange, March 2010                    
    For the 8th Edition of the MATLAB Primer (published by CRC Press)  
    I wrote a script that downloaded and parsed all 9489 submissions   
    to the MATLAB File Exchange (as of March 12, 2010, 8am), at:   .             
    Each submission was parsed to determine how many times each of     
    1319 keywords appears.  The list of keywords to search for was     
    obtained by parsing the MATLAB Help documentation.  In the primary 
    matrix (Problem.A), the entry A(i,j) is the nubmer of times that   
    the ith keyword appears in the jth "file" (each of the submissions 
    to the MATLAB File Exchange is called a "file", although each      
    submission often consists of more than one actual file).           
    Problem.aux.key{i} is the ith keyword, and is    
    the MATLAB File ID corresponding to the jth column of the matrix A.
    The first 454 rows of the A matrix correspond to the 454 functions 
    or keywords that appear in the "MATLAB Top 500" list of most-      
    frequently used functions, keywords, and operators in the 8th      
    Edition of the MATLAB Primer.  The remaining are operators         
    (+ - / * . etc) to round out the "Top 500" (these do not appear    
    in the Problem.A matrix since parsing them proved difficult).      
    Note that some editorial adjustments were made to the Top 500.     
    In particular, deprecated functions were removed.  Some of the     
    trigonometric functions are rarely used, but all of them were      
    included in the "Top 500" to make a complete set.  You can         
    visualize this with semilogy(sum(A,2)).  The rows of A are         
    mostly sorted in decreasing row-sum, except for rows 430 to        
    470 or so.                                                         
    This matrix was constructed in March 2010 by Tim Davis and added   
    to the collection in July 2012; Tim Davis is solely responsible    
    for this matrix.  It was not submitted by or authorized by         
    The MathWorks, Inc, but since the File Exchange is now under       
    a BSD license, this is included in the collection as a legitimate  
    derivative work.                                                   

    SVD-based statistics:
    null space dimension182
    full numerical rank?no
    singular value gap8.56195e+11

    singular values (MAT file):click here
    SVD method used:s = svd (full (R)) ; where [~,R,E] = spqr (A') with droptol of zero

    Davis/FX_March2010 svd

    For a description of the statistics displayed above, click here.

    Maintained by Tim Davis, last updated 12-Mar-2014.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.