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From Apache Wiki <wikidi...@apache.org>
Subject [Lucene-hadoop Wiki] Trivial Update of "Hbase/ShellPlans" by udanax
Date Tue, 28 Aug 2007 06:02:25 GMT
Dear Wiki user,

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The following page has been changed by udanax:
http://wiki.apache.org/lucene-hadoop/Hbase/ShellPlans

------------------------------------------------------------------------------
  
  == Background ==
  I expect Hadoop + Hbase to handle sparsity and data explosion very well in near future.
Moreover, i believe the design of the multi-dimensional map structure and the 3d space model
of the data are optimized for rapid ad-hoc information retrieval in any orientation, as well
as for fast, flexible calculation and transformation of raw data based on formulaic relationships.
It is advantageous with respect to Analysis Processing as it allows users to easily formulate
complex queries, and filter or slice data into meaningful subsets, among other things.
+ 
+ == Parallelization ==
+ 
+ Altools provides automatic parallelization of the most time-consuming relational/matrix/vector
operations, and will ensure that the iterative solvers are scalable.
+ 
+  * Parallel Processing of Relational Data
+  * Parallel Algorithms of Multi-Dimensional Matrix Operation
+  * Parallel Gaussian Elimination Algorithm
  
  ----
  
@@ -77, +85 @@

  Hbase.altools > store B to table('result_table');
  }}}
  
+ == Matrix Operators ==
+ '''Note''' that matrix operations are the core of many linear systems.
- == Matrix Arithmetic Operators ==
+ === Arithmetic Operators ===
  ||<bgcolor="#E5E5E5">'''Operator''' ||<bgcolor="#E5E5E5">'''Explanation''' ||
  ||Addition ||<99%>'''Adding''' entries with the same indices. [[BR]][[BR]]~-''A =
Matrix('m_table','cf_1');[[BR]]B = Matrix('m_table','cf_2');[[BR]]C = A + B; '''// c,,ij,,
= a,,ij,, + b,,ij,, (i : row key, j : column key)''' ''-~ ||
  ||Subtraction ||<99%>'''Subtracting''' entries with the same indices.[[BR]][[BR]]~-''A
= Matrix('m_table','cf_1');[[BR]]B = Matrix('m_table','cf_2');[[BR]]C = A - B; '''// c,,ij,,
= a,,ij,, - b,,ij,, (i : row key, j : column key)''' ''-~ ||
@@ -115, +125 @@

  ||LU ||<99%>'''LU Decomposition'''[[BR]]A procedure for decomposing an N by N matrix
A into a product of a lower triangular matrix L and an upper triangular matrix U, LU = A.[[BR]]'''Functions'''
: ~-''getL(), getU(), isSingular(), getPivot()''-~ [[BR]][[BR]]~-''A = Matrix('m_table','cf_1');[[BR]]B
= LUDecomposition(A);[[BR]]C = B.getU();[[BR]]D = B.getL();''-~||
  ||QR ||<99%>'''QR Decomposition'''[[BR]]For an m-by-n matrix A with m >= n, the
QR decomposition is an m-by-n orthogonal matrix Q and an n-by-n upper triangular matrix R
so that A = Q*R.[[BR]]'''Functions''' : ~-''getH(), getQ(), getR()''-~[[BR]][[BR]]~-''A =
Matrix('m_table','cf_1');[[BR]]B = QRDecomposition(A);[[BR]]C = B.getH();''-~||
  ||Cholesky ||<99%>'''Cholesky Decomposition'''[[BR]]It is a special case of LU decomposition
applicable only if matrix to be decomposed is symmetric positive definite.[[BR]]'''Functions'''
: ~-''getL(), getU(), isSPD()''-~ [[BR]][[BR]]~-''A = Matrix('m_table','cf_1');[[BR]]B = CholeskyDecomposition(A);[[BR]]C
= B.getL();''-~||
- ||SVD ||<99%>'''SV(Singular Value) Decomposition'''[[BR]]For an m-by-n matrix A with
m >= n, the singular value decomposition is an m-by-n orthogonal matrix U, an n-by-n diagonal
matrix S, and an n-by-n orthogonal matrix V so that A = U*S*V'.[[BR]]'''Functions''' : ~-''getS(),
getU(), getV()''-~ [[BR]][[BR]]~-''A = Matrix('m_table','cf_1');[[BR]]B = SVDecomposition(A);[[BR]]C
= B.getU();''-~||
+ ||SVD ||<99%>'''SV(Singular Value) Decomposition'''[[BR]]For an m-by-n matrix A with
m >= n, the singular value decomposition is an m-by-n orthogonal matrix U, an n-by-n diagonal
matrix S, and an n-by-n orthogonal matrix V so that A = U*S*V'.[[BR]]'''Functions''' : ~-''getS(),
getU(), getV(), norm2(), rank()''-~ [[BR]][[BR]]~-''A = Matrix('m_table','cf_1');[[BR]]B =
SVDecomposition(A);[[BR]]C = B.getU();''-~||
  
  {{{
  //Set up the matrix M from mapped matrix in hbase.
@@ -170, +180 @@

    * ~-''d'' : Column number of matrix X-~
    * ~-''m'' : Rank of matrix X ( ≤ min(t,d) )-~
  
- 
  ||Row Key ||<-6>Column Families ||
  ||<rowbgcolor="#ececec">term ||<-2> corpus: ||<-2>link: ||<-2>..
||
  ||t01 ||corpus:c01 ||0 ||link:cnn.com ||1 ||.. ||.. ||
@@ -184, +193 @@

  Hbase.altools > X = Matrix('t_table','corpus'); 
  }}}
  
+ This example used tf*idf for more efficient and economical calculations.
+ 
   * ~-''w,,ij,, = tf,,ij,, '''·''' log( N/df,,j,, )''-~
+   * ~-''w'' : weighted value-~
+   * ~-''tf'' : the number of times the word appears in a i-th document-~
+   * ~-''N'' : the number of documents of an entire corpus-~
+   * ~-''df'' : the number of documents containing the j-th term-~
  
  ||<rowbgcolor="#ececec"> ||c01 ||c02 ||.. ||
  ||<bgcolor="#ececec">t01 ||0.00 ||0.00 ||.. ||
  ||<bgcolor="#ececec">t02 ||2.08 ||0.00 ||.. ||
  ||<bgcolor="#ececec">.. ||.. ||.. ||.. ||
  
+ Weighted Matrix W
+ 
  {{{
  //Diagonal eigenvalue S
  
- Hbase.altools > M = X.SVDecomposition(); 
+ Hbase.altools > M = W.SVDecomposition(); 
  Hbase.altools > S = M.getS();
  }}}
  
@@ -207, +224 @@

  Hbase.altools > D = M.getV();
  }}}
  
- Dimension reduction (k = 3)
+ SVD allows a simple strategy for optimal approximate fit using smaller matrices. If the
singular
+ values in S0 are ordered by size, the first k largest values may be kept and the remaining
smaller ones
+ set to zero. The product of the resulting matrices is a matrix X′ which is only approximately
equal to X,
+ and is of rank k. Since zeros were introduced into S0, the representation can be simplified
by deleting
+ the zero rows and columns of S0 to obtain a new diagonal matrix S, and deleting the corresponding
+ columns of T0 and D0 to obtain T and D respectively. The result is a reduced model :
+ 
+  * ~-''X′ = TSDT ≈ X''-~
+ 
+ which is the rank-k model with the best possible least square fit to X.
+ 
+ This example used (k = 3).
  
  = Papers =
   * [http://www.uib.no/People/nmabh/art/hpj.pdf High performance numerical libraries in Java]

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