Manipulating list with sub-lists of different lengths

up vote
5
down vote

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Consider the following list, which is composed of sublists with different lengths

, 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3

How can this list be transformed into a list of the first elements, second elements, etc...i.e, the out come I would like to produce

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

asked Aug 19 at 14:27

jarhead

689413

related: Transpose uneven lists
â€“Â user1066
Aug 20 at 7:40

add a commentÂ |Â

up vote
5
down vote

favorite

Consider the following list, which is composed of sublists with different lengths

, 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3

How can this list be transformed into a list of the first elements, second elements, etc...i.e, the out come I would like to produce

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

asked Aug 19 at 14:27

jarhead

689413

related: Transpose uneven lists
â€“Â user1066
Aug 20 at 7:40

add a commentÂ |Â

up vote
5
down vote

favorite

Consider the following list, which is composed of sublists with different lengths

, 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3

How can this list be transformed into a list of the first elements, second elements, etc...i.e, the out come I would like to produce

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

asked Aug 19 at 14:27

jarhead

689413

Consider the following list, which is composed of sublists with different lengths

, 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3

How can this list be transformed into a list of the first elements, second elements, etc...i.e, the out come I would like to produce

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

list-manipulation

asked Aug 19 at 14:27

jarhead

689413

asked Aug 19 at 14:27

jarhead

689413

asked Aug 19 at 14:27

jarhead

689413

asked Aug 19 at 14:27

jarhead

689413

asked Aug 19 at 14:27

jarhead

689413

related: Transpose uneven lists
â€“Â user1066
Aug 20 at 7:40

add a commentÂ |Â

related: Transpose uneven lists
â€“Â user1066
Aug 20 at 7:40

related: Transpose uneven lists
â€“Â user1066
Aug 20 at 7:40

add a commentÂ |Â

3 Answers
3

active

oldest

votes

up vote
4
down vote

accepted

Maybe this way?

data = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3;
get[a_, k_] := Map[If[Length[#] >= k, #[[k]], Nothing] &, a];
get[data, 1]
get[data, 2]
get[data, 3]
get[data, 4]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3

7, 2, 5, 5, 4, 7

4, 8

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

add a commentÂ |Â

up vote
6
down vote

You can use Flatten:

list = 
 ,
 2,2,7,2,
 6,3,
 5,4,5,5,
 4,6,4,7,4,8,
 ,
 6,3
;

Flatten[list, 2]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

answered Aug 19 at 15:00

Carl Woll

57.7k273149

add a commentÂ |Â

up vote
4
down vote

lst = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5,
 4, 6, 4, 7, 4, 8, , 6, 3;

Extract[lst, #] & /@ GatherBy[Position[lst, _, 2, Heads -> False], Last]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8

parts[l_][k_] := Join @@ MapIndexed[If[Last[#2] == k, #, ## &] &, l, 2]
parts[lst] /@ Range[4]]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8,

edited Aug 19 at 15:22

answered Aug 19 at 14:54

kglr

161k8185384

add a commentÂ |Â

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3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

up vote
4
down vote

accepted

Maybe this way?

data = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3;
get[a_, k_] := Map[If[Length[#] >= k, #[[k]], Nothing] &, a];
get[data, 1]
get[data, 2]
get[data, 3]
get[data, 4]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3

7, 2, 5, 5, 4, 7

4, 8

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

add a commentÂ |Â

up vote
4
down vote

accepted

Maybe this way?

data = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3;
get[a_, k_] := Map[If[Length[#] >= k, #[[k]], Nothing] &, a];
get[data, 1]
get[data, 2]
get[data, 3]
get[data, 4]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3

7, 2, 5, 5, 4, 7

4, 8

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

add a commentÂ |Â

up vote
4
down vote

accepted

Maybe this way?

data = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3;
get[a_, k_] := Map[If[Length[#] >= k, #[[k]], Nothing] &, a];
get[data, 1]
get[data, 2]
get[data, 3]
get[data, 4]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3

7, 2, 5, 5, 4, 7

4, 8

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

Maybe this way?

data = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5, 4, 6, 4, 7, 4, 8, , 6, 3;
get[a_, k_] := Map[If[Length[#] >= k, #[[k]], Nothing] &, a];
get[data, 1]
get[data, 2]
get[data, 3]
get[data, 4]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3

7, 2, 5, 5, 4, 7

4, 8

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

answered Aug 19 at 14:35

Henrik Schumacher

38.7k253114

add a commentÂ |Â

up vote
6
down vote

You can use Flatten:

list = 
 ,
 2,2,7,2,
 6,3,
 5,4,5,5,
 4,6,4,7,4,8,
 ,
 6,3
;

Flatten[list, 2]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

answered Aug 19 at 15:00

Carl Woll

57.7k273149

add a commentÂ |Â

up vote
6
down vote

You can use Flatten:

list = 
 ,
 2,2,7,2,
 6,3,
 5,4,5,5,
 4,6,4,7,4,8,
 ,
 6,3
;

Flatten[list, 2]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

answered Aug 19 at 15:00

Carl Woll

57.7k273149

add a commentÂ |Â

up vote
6
down vote

You can use Flatten:

list = 
 ,
 2,2,7,2,
 6,3,
 5,4,5,5,
 4,6,4,7,4,8,
 ,
 6,3
;

Flatten[list, 2]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

answered Aug 19 at 15:00

Carl Woll

57.7k273149

You can use Flatten:

list = 
 ,
 2,2,7,2,
 6,3,
 5,4,5,5,
 4,6,4,7,4,8,
 ,
 6,3
;

Flatten[list, 2]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3, 7, 2, 5, 5, 4, 7, 4, 8

answered Aug 19 at 15:00

Carl Woll

57.7k273149

answered Aug 19 at 15:00

Carl Woll

57.7k273149

answered Aug 19 at 15:00

Carl Woll

57.7k273149

answered Aug 19 at 15:00

Carl Woll

57.7k273149

add a commentÂ |Â

up vote
4
down vote

lst = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5,
 4, 6, 4, 7, 4, 8, , 6, 3;

Extract[lst, #] & /@ GatherBy[Position[lst, _, 2, Heads -> False], Last]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8

parts[l_][k_] := Join @@ MapIndexed[If[Last[#2] == k, #, ## &] &, l, 2]
parts[lst] /@ Range[4]]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8,

edited Aug 19 at 15:22

answered Aug 19 at 14:54

kglr

161k8185384

add a commentÂ |Â

up vote
4
down vote

lst = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5,
 4, 6, 4, 7, 4, 8, , 6, 3;

Extract[lst, #] & /@ GatherBy[Position[lst, _, 2, Heads -> False], Last]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8

parts[l_][k_] := Join @@ MapIndexed[If[Last[#2] == k, #, ## &] &, l, 2]
parts[lst] /@ Range[4]]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8,

edited Aug 19 at 15:22

answered Aug 19 at 14:54

kglr

161k8185384

add a commentÂ |Â

up vote
4
down vote

lst = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5,
 4, 6, 4, 7, 4, 8, , 6, 3;

Extract[lst, #] & /@ GatherBy[Position[lst, _, 2, Heads -> False], Last]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8

parts[l_][k_] := Join @@ MapIndexed[If[Last[#2] == k, #, ## &] &, l, 2]
parts[lst] /@ Range[4]]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8,

edited Aug 19 at 15:22

answered Aug 19 at 14:54

kglr

161k8185384

lst = , 2, 2, 7, 2, 6, 3, 5, 4, 5, 5,
 4, 6, 4, 7, 4, 8, , 6, 3;

Extract[lst, #] & /@ GatherBy[Position[lst, _, 2, Heads -> False], Last]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8

parts[l_][k_] := Join @@ MapIndexed[If[Last[#2] == k, #, ## &] &, l, 2]
parts[lst] /@ Range[4]]

2, 2, 6, 3, 5, 4, 4, 6, 6, 3,

7, 2, 5, 5, 4, 7,

4, 8,

edited Aug 19 at 15:22

answered Aug 19 at 14:54

kglr

161k8185384

edited Aug 19 at 15:22

answered Aug 19 at 14:54

kglr

161k8185384

answered Aug 19 at 14:54

kglr

161k8185384

answered Aug 19 at 14:54

kglr

161k8185384

add a commentÂ |Â

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