2015-05-04 84 views

回答

1
M := LinearAlgebra:-RandomMatrix(4); 

         [-93 -32  8  44] 
         [      ] 
         [-76 -74 69  92] 
        M := [      ] 
         [-72  -4 99 -31] 
         [      ] 
         [ -2  27 29  67] 


M[2..4,1..2]; 

          [-76 -74] 
          [   ] 
          [-72  -4] 
          [   ] 
          [ -2  27] 


M[2..3,..]; 

         [-76 -74 69  92] 
         [      ] 
         [-72  -4 99 -31] 


M[..,2..4]; 

          [-32  8  44] 
          [    ] 
          [-74 69  92] 
          [    ] 
          [ -4 99 -31] 
          [    ] 
          [ 27 29  67] 

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