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MATLAB sparse OiN@ӧx}ഫ}x}AҦpG

Example 1: 05-}x}/sparse01.mA = [1 0 0 0 0; 0 0 0 3 0; 0 4 0 0 0]; % x} S = sparse(A) % Nx} A ഫ}x} SS = (1,1) 1 (3,2) 4 (2,4) 3

ѦiݥXAS O@ӵ}x}AMATLAB uxsUӫDsm]YGU (1,1)B(3,2)B(2,4)^ Mȡ]1B4B3^CYnx} A M S ҦΪOjpAiJpUG

Example 2: 05-}x}/sparse02.mclear all; % MҦܼ A = [1 0 0 0 0; 0 0 0 3 0; 0 4 0 0 0]; % x} S = sparse(A); % Nx} A ഫ}x} S whos Name Size Bytes Class Attributes A 3x5 120 double S 3x5 96 double sparse

Ѧiҵ}x} S ΰO骺줸ռƥء]96 Bytes^x} A]120 Bytes^pܦhC

ڭ̤]iHϥ sparse OӪ͵}x}AϥλykpUG

S = sparse(i, j, s, m, n);

䤤 i OCޡAj OޡAs ODsҧΦVqAm O s CסAn O s סC iBjBs O׬ۦPVqAs(k) GUЧYO i(k) j(k)CҦpAHUykiHͻPeҬۦP}x} SG

Example 3: 05-}x}/sparse03.mS = sparse([1 3 2], [1 2 4], [1 4 3], 3, 5);

z]iHb sparse O[WĤؿJܼơAN̦hiHeǪDsӯAϱoziHA[JDsA Ӥܾӵ}x}cC

MATLAB ѤFt@ӫO spdiagsAiѹ﨤uӫغc@ӵ}x}A@榡pUG

S = spdiags(D, d, m, n)

䤤 D C@ӪNx}﨤uVqAd N﨤um]0 ND﨤uA-1 NVU첾@쪺﨤uA 1 NVW첾@쪺﨤uA̦^Am P n hONx}C׻PסCҦpG

Example 4: 05-}x}/spdiags01.mD = [2 7; 4 9; 1 3]; d = [1 -1]; S = spdiags(D, d, 4, 3) A = full(S)S = (2,1) 7 (1,2) 4 (3,2) 9 (2,3) 1 (4,3) 3 A = 0 4 0 7 0 1 0 9 0 0 0 3

ѦiݥX D ӦVq [2 4 1]' [7 9 3]'AOOx} A ӹ﨤uVqA@ӦD﨤uWAt@ӦD﨤uUC]bx} D Ĥ@VqAڭ̥uΨFĤGβĤTӤAĤ@Ӥh]WVx}ɽdӳQu屼FvI^

@몺 load save OA]iHBz}x}AxsGi MAT ɮסCt@ӱ`Ψ쪺OO spconvertA iN@ m3 x}ഫ}x}A䤤Ĥ@NCޡAĤGNޡAĤThODsȡC ҦpG

Example 5: 05-}x}/spconvert01.mload spmat.dat spmat S = spconvert(spmat)spmat = 1 1 2 3 2 4 2 4 1 8 3 5 S = (1,1) 2 (3,2) 4 (8,3) 5 (2,4) 1

bWzdҤAspmat Ĥ@βĤGN}x}CޤΪޡAĤThOȡAg spconvertAڭ̧Yiغc}x}C
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