Find an index of a cell whose element satisfies a condition

34 Ansichten (letzte 30 Tage)
Diaa
Diaa am 18 Jun. 2021
Kommentiert: DGM am 18 Jun. 2021
Is there a way to economically fix the code below to make it work so that it returns the index of the cell element whose array has the number 1 in its second column?
c = {[1,2,3], [2,3,1], [3,1,2]};
find(c{:}(:,2)==1) % expected result is the cell index 3
The code above gets me this error:
Intermediate brace {} indexing produced a comma-separated list with 3 values, but it must produce a single value to perform subsequent indexing operations.
I came up with this one
find(~cellfun(@isempty,(cellfun(@(x) find(x(:,2)==1,1),c,'un',0))))
but I would like to find some other efficient ways of doing it.

Akzeptierte Antwort

Star Strider
Star Strider am 18 Jun. 2021
Try this —
c = {[1,2,3], [2,3,1], [3,1,2]};
idx = cellfun(@(x)x(:,2)==1, c, 'Unif',0)
idx = 1×3 cell array
{[0]} {[0]} {[1]}
Out = find([idx{:}])
Out = 3
.

Weitere Antworten (1)

DGM
DGM am 18 Jun. 2021
This is one way:
c = {[1,2,3], [2,3,1], [3,1,2], [1,2,3], [2,3,1], [3,1,2]};
idx = find(cellfun(@(x) x(2)==1,c))
idx = 1×2
3 6
  2 Kommentare
Diaa
Diaa am 18 Jun. 2021
I think your code will fail in this example
c = {[1,2,3;1,2,3], [2,3,1], [3,1,2;3,6,9]}; find(cellfun(@(x) x(2)==1,c))
DGM
DGM am 18 Jun. 2021
Ah yeah. I had read "second column" as "second element".

Melden Sie sich an, um zu kommentieren.

Kategorien

Mehr zu Structures finden Sie in Help Center und File Exchange

Produkte


Version

R2021a

Community Treasure Hunt

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

Start Hunting!

Translated by