Linux -Delete Directory

1. delete file
% rm test.txt

2. delete directory
% rm -r DIRECTORY

3. force delete directory
% rm -rf DIRECTORY_Name

matlab矩阵按某一行的值排序

比如一个二维举证[1,3,2,5,9;8,6,7,1,3]
怎么实现按第一行降幂排序为[1,2,3,5,9;8,7,6,1,3]

问题补充：

已经知道怎么做了
operation 1: 

        A=[1,3,2,5,9;8,6,7,1,3]

RESULT: 

A =

     1     3     2     5     9
     8     6     7     1     3

operation 2: 
        [A(1,:),B]=sort(A(1,:),2,'ascend');

RESULT:

A =

     1     2     3     5     9
     8     6     7     1     3


B =

     1     3     2     4     5    - changed A(1,:) 's corresponding index number 

operation 3:

        A(2,:)=A(2,B);

RESULT:

A =

     1     2     3     5     9
     8     7     6     1     3

ref：http://zhidao.baidu.com/question/129962854