Working with cell arrays

2 Ansichten (letzte 30 Tage)
L'O.G.
L'O.G. am 5 Mai 2023
Kommentiert: Stephen23 am 8 Mai 2023
I would like to separate columns in an array based on the unique values of the first column. I think the way to do this is a cell array since the vectors would be of different length. Is there a way to vectorize this? For example, the following array
example = [
5 2.3 1.7
5 0.2 9.1
99 3.3 3.6
99 4.1 3.2
99 5.1 2.2
103 1.1 6.8
];
should give
A{1} = [2.3,0.2];
A{2} = [3.3,4.1,5.1];
A{3} = [1.1];
B{1} = [1.7,9.1];
B{2} = [3.6,3.2,2.2];
B{3} = [6.8];
(since there are three unique values in column 1 of the example)

Akzeptierte Antwort

Paul
Paul am 5 Mai 2023
example = [
5 2.3 1.7
5 0.2 9.1
99 3.3 3.6
99 4.1 3.2
99 5.1 2.2
103 1.1 6.8
];
G = findgroups(example(:,1));
A = splitapply(@(x) mat2cell(x,numel(x)),example(:,2),G);
B = splitapply(@(x) mat2cell(x,numel(x)),example(:,3),G);
A,B
A = 3×1 cell array
{2×1 double} {3×1 double} {[ 1.1000]}
B = 3×1 cell array
{2×1 double} {3×1 double} {[ 6.8000]}
A{1}
ans = 2×1
2.3000 0.2000
B{1}
ans = 2×1
1.7000 9.1000
  1 Kommentar
Stephen23
Stephen23 am 8 Mai 2023
Also without the MAT2CELL call:
X = [
5 2.3 1.7
5 0.2 9.1
99 3.3 3.6
99 4.1 3.2
99 5.1 2.2
103 1.1 6.8
];
G = findgroups(X(:,1));
A = accumarray(G,X(:,2),[],@(a){a});
B = accumarray(G,X(:,3),[],@(a){a});
A,B
A = 3×1 cell array
{2×1 double} {3×1 double} {[ 1.1000]}
B = 3×1 cell array
{2×1 double} {3×1 double} {[ 6.8000]}
A{1}
ans = 2×1
2.3000 0.2000
B{1}
ans = 2×1
1.7000 9.1000

Melden Sie sich an, um zu kommentieren.

Weitere Antworten (0)

Produkte


Version

R2021b

Community Treasure Hunt

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

Start Hunting!

Translated by