请问mathematic如何取出数组的某一列

xiaoqiushui318

比如一个3×3的数组，我想取出其第二列元素应该用什么操作？多谢

FreddyMusic

That's it.

Extract [  ]

1. 
   
2. 
   
3. (mm = Array[10#1 + #2 &, {3, 3}]) // MatrixForm
   
4. 
   
5. Extract[mm, {{1, 2}, {2, 2}, {3, 2}}]
   
6. 
   

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[ 本帖最后由 FreddyMusic 于 2007-5-2 17:51 编辑 ]

xiaoqiushui318

今天查到一个更方便的命令
可以这样子来取第二列 mm[[All,2]]

FreddyMusic

good.

FreddyMusic

A NEW Method

1. 
   
2. 
   
3. <<Statistics`DataManipulation`
   
4. data = {{a, 3}, {b, 6}, {c, 4}, {d, i}, {e, 5}, {f, 4}}
   
5. col2 = Column[data, 2]
   
6. 
   

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