Description of slparblocks

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slparblocks

PURPOSE

SLPARBLOCKS Gets the blocks from partition structure

SYNOPSIS

function blocks = slparblocks(ps)

DESCRIPTION

SLPARBLOCKS Gets the blocks from partition structure

 $ Syntax $
   - blocks = slparblocks(ps)

 $ Arguments $
   - ps:       the partition structure generated from slpartition
   - blocks:   the cell array of block ranges

 $ Description $
   - blocks = slparblocks(ps) gets the a cell array of blocks 
     corresponding to the partition structure. If there are d dimensions
     and m1, m2, ..., md partitions along each dimension. Then an
     m1 x m2 x ... x md cell array will be returned, with each cell
     containing a 2 x d array, in the form of 
     [s1, s2, ..., sd; e1, e2, ..., ed]. It means that the block of
     data will be extracted from an whole array A as
     A(s1:e1, s2:e2, ..., sd:ed).

 $ History $
   - Created by Dahua Lin, on Jul 29th, 2006

CROSS-REFERENCE INFORMATION

This function calls:

• slallsubinds SLALLSUBINDS Generate all sub-indices for all elements of the array

This function is called by:

• slpwcomp_blks SLPWCOMP_BLKS Computes pairwise value matrix
• slpartitionpca SLPARTITIONPCA Performs Partition-based PCA and saves the models

SOURCE CODE

0001 function blocks = slparblocks(ps)
0002 %SLPARBLOCKS Gets the blocks from partition structure
0003 %
0004 % $ Syntax $
0005 %   - blocks = slparblocks(ps)
0006 %
0007 % $ Arguments $
0008 %   - ps:       the partition structure generated from slpartition
0009 %   - blocks:   the cell array of block ranges
0010 %
0011 % $ Description $
0012 %   - blocks = slparblocks(ps) gets the a cell array of blocks
0013 %     corresponding to the partition structure. If there are d dimensions
0014 %     and m1, m2, ..., md partitions along each dimension. Then an
0015 %     m1 x m2 x ... x md cell array will be returned, with each cell
0016 %     containing a 2 x d array, in the form of
0017 %     [s1, s2, ..., sd; e1, e2, ..., ed]. It means that the block of
0018 %     data will be extracted from an whole array A as
0019 %     A(s1:e1, s2:e2, ..., sd:ed).
0020 %
0021 % $ History $
0022 %   - Created by Dahua Lin, on Jul 29th, 2006
0023 %
0024 
0025 
0026 % calculate block numbers
0027 
0028 d = length(ps);
0029 
0030 blknums = zeros(1, d);
0031 for i = 1 : d
0032     blknums(i) = length(ps(i).sinds);
0033 end
0034 
0035 % get block ranges
0036 
0037 blkinds = slallsubinds(blknums);
0038 NBlks = prod(blknums);
0039 blkinds = reshape(blkinds, [d, NBlks]);
0040 
0041 Smat = zeros(d, NBlks);
0042 Emat = zeros(d, NBlks);
0043 for i = 1 : d
0044     Smat(i, :) = ps(i).sinds(blkinds(i, 1:NBlks));
0045     Emat(i, :) = ps(i).einds(blkinds(i, 1:NBlks));
0046 end
0047 
0048 
0049 % convert from block range array to block cell array
0050 
0051 Smat = reshape(Smat, [1, d*NBlks]);
0052 Emat = reshape(Emat, [1, d*NBlks]);
0053 Bmat = [Smat; Emat];
0054 clear Smat Emat;
0055 
0056 tempd = zeros(1, NBlks);
0057 tempd(:) = d;
0058 blocks = mat2cell(Bmat, 2, tempd);
0059 
0060 if d == 1
0061     blocks = blocks(:);
0062 else
0063     blocks = reshape(blocks, blknums);
0064 end
0065 
0066 
0067 
0068 
0069

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