清空筛选条件
清空筛选条件

Create n matrix from one matrix according to elements of a column?

1 次查看（过去 30 天）
Sleh Eddine Brika
Sleh Eddine Brika 2016-4-15
评论： Sleh Eddine Brika 2016-4-16
I have a sorted matrix (according to the element of the third column)
A = [ 4 2 0 ;3 7 0 ; 8 9 3 ; 7 5 3; 4 4 3]
I want to get n matrix (in this case 2) from A, according to the value of the element of the third column, to get
M1 = [ 4 2 0 ; 3 7 0]
M2 = [8 9 3 ; 7 5 3; 4 4 3].
I know how many matrix I will have and the different elements to study using the function 'unique' that provide me a matrix (for this case) B=[0;3].
I tried with the functions 'genvarname' and 'eval' but I didn't find a good solution.

请先登录，再回答此问题。

采纳的回答

Andrei Bobrov
Andrei Bobrov 2016-4-15
编辑：Andrei Bobrov 2016-4-15
[~,~,c] = unique(A(:,end));
M = accumarray(c,(1:size(A,1))',[],@(x){A(x,:)});
  2 个评论
Sleh Eddine Brika
Sleh Eddine Brika 2016-4-15
It's so wonderful thank you !A really interesting command, but I really need to get separated Matrix and do you know how to dynamically generate matrix name

请先登录，再进行评论。

更多回答（1 个）

Azzi Abdelmalek
Azzi Abdelmalek 2016-4-15
A = [ 4 2 0 ;3 7 0 ; 8 9 3 ; 7 5 3; 4 4 3]
[ii,jj,kk]=unique(A(:,3))
out=accumarray(kk,1,[],@(x) {A(x,:)})
% the first matrix and the second are
out{1}
out{2}
It's not a good idea to generate multiple names http://matlab.wikia.com/wiki/FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F
  3 个评论
显示 1更早的评论
Azzi Abdelmalek
Azzi Abdelmalek 2016-4-15
@Sleh Eddine, it's easier to call your matrices with one variable and indices: out{1}, out{2},... then using multiple variables!

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Loops and Conditional Statements 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by