Bringing arrays to the same length

Question

Lev Mihailov 2022-3-2

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1661815-bringing-arrays-to-the-same-length

编辑： Rik 2022-3-2

There are three arrays (two vectors and a matrix), I need to bring them to the same length

a=[ 1.2,1.3,1.4]; % by array "a" i need to sort the values ​​in array "b" and "m"
b=[ 1.2,0.9,1.3,2.6,1.4];
m=[1,2;26,90;1,2;120,0;1,0];
% what do i need to get
ba=[ 1.2,1.3,1.4];
ma=[1,2;1,2;1,0];

I will be glad to any advice

2 个评论
显示无隐藏无

DGM 2022-3-2

编辑：DGM 2022-3-2

在 MATLAB Online 中打开

At first glance, I thought you're looking for the intersections:

a=[1.2,1.3,1.4]; % by array "a" i need to sort the values in array "b" and "m"

b=[1.2,0.9,1.3,2.6,1.4];

m=[1,2;26,90;1,2;120,0;1,0];

ba = intersect(b,a)

ba = 1×3

1.2000 1.3000 1.4000

ma = intersect(m,a)

ma = 0×1 empty double column vector

... but there's no intersection between m and a. I don't know what rules you use to get the results you describe. Is ma a function of the indices of the intersection of b and a?

[ba idx] = intersect(b,a);
ma = m(idx,:)
ma = 3×2
     1     2
     1     2
     1     0

Benjamin Kraus 2022-3-2

I'm having some trouble understanding your question.

If I understand correctly, you are trying to calculate the values in ba and ma based somehow on the values of a, b, and m, but I don't see how you calculate the values in ma from any of the vectors, and ba appears to be equal to a. Can you give more description (in words) of the algorithm you are hoping to use to derive ba and ma based on a, b, and m?

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Rik 2022-3-2

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1661815-bringing-arrays-to-the-same-length#answer_907885

编辑：Rik 2022-3-2

在 MATLAB Online 中打开

There are two issues with the solution by Arif:

It uses find on a logical array, but that is only used to index an array
It assume the the first column in m will be 1 for all the rows we're looking for

The edits below solve both.

a=[ 1.2,1.3,1.4];
b=[ 1.2,0.9,1.3,2.6,1.4];
m=[1,2;26,90;1,2;120,0;1,0];
[L,idx]=ismember(a,b); % find the element of a in b
ba=a(L)
ba = 1×3
    1.2000    1.3000    1.4000
ma=m(idx(L),:)
ma = 3×2
     1     2
     1     2
     1     0

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

Answer 2

Arif Hoq 2022-3-2

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1661815-bringing-arrays-to-the-same-length#answer_907860

编辑：Arif Hoq 2022-3-2

在 MATLAB Online 中打开

try this:

a=[ 1.2,1.3,1.4]; % by array "a" i need to sort the values in array "b" and "m"
b=[ 1.2,0.9,1.3,2.6,1.4];
m=[1,2;26,90;1,2;120,0;1,0];
[idx]=find(ismember(b,a)); % find the element of a in b
ba=b(idx)
ba = 1×3
    1.2000    1.3000    1.4000
ma=m((m==1),:) % find the first element=1
ma = 3×2
     1     2
     1     2
     1     0