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发表于 2010-1-20 14:59:18
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Colon Notation
1 ~. \# W1 c x! K$ ^Matlab offers some powerful methods for creating arrays and for taking them apart.
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a=magic(5)
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a(2,3)
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3 L! ^5 k g1 ANow we will use the colon notation to select a column of a.
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a(:,3)
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a
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6 w& y, x& U6 ]8 ~7 \a(:,3:5)) A7 w3 o9 ~) D8 O" n5 l5 C7 C1 f
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a(2:4,3:5)5 T+ o- D3 F, {- T/ {0 y" k
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/ E7 O y0 h3 ?- F7 l/ h) ?You can put a vector into a row or column position within a.
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& J0 R- @8 S' Y) P1 @a([2 5],[2 4 5])
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You can also make assignment statements using a vector or a matrix. $ r g5 E) F4 D
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b([1 2],:)=a([1 2],:)' {" }( d9 W0 M j$ ~ O
2 ~; c/ o6 v$ A$ o, Ba(:,[1 2])=b(:,[3 5])' N. l9 [5 t! Q# {& Q
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a(:,[1 5])=a(:,[5 1])
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a=a(:,5:-1:1)
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2 E! \2 l w9 }2 i9 u# pWhen you a insert a 0-1 vector into the column position then the columns which correspond to 1's are displayed.
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a(v,:)
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This has been a sample of the basic MATLAB functions and the matrix manipulation techniques. At the end of the tutorial there is a listing of functions. The functions that you have available will vary slightly from version to version of MATLAB. By typing
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you will get access to descriptions of all the Matlab functions |
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