Bringing arrays to the same length

16 次查看（过去 30 天）
Lev Mihailov
Lev Mihailov 2022-3-2
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
DGM
DGM 2022-3-2
编辑：DGM 2022-3-2
Ran in:
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
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。

回答（2 个）

Rik
Rik 2022-3-2
编辑：Rik 2022-3-2
Ran in:
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
Arif Hoq
Arif Hoq 2022-3-2
编辑：Arif Hoq 2022-3-2
Ran in:
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

类别

在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息

标签

产品

Community Treasure Hunt

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

Start Hunting!

Translated by