How to insert elements at different locations of a given list

Clash Royale CLAN TAG#URR8PPP

up vote
4
down vote

favorite

Say a list is given as

list = a, b, c, d, r, m, n;

Suppose I want to insert 2 and 3 at position 3 and 7, respectively.

Insert[list, 2, 3] puts 2 at position 3, but Insert[list, 2, 3, 3, 7] does nothing.

How is it possible?

list-manipulation

share|improve this question

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

asked 3 hours ago

Soumyajit Roy

1358

• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  Dirty trick: Block[k = 0, Insert[a, b, c, d, r, m, n, Unevaluated[2, 3[[++k]]], 3, 7]]
  – J. M. is somewhat okay.♦
  3 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @J.M. Wow, that one is really dirty. I had to read it several times to understand it half way at least...
  – Henrik Schumacher
  1 hour ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @Henrik, I didn't want to post it as an answer lest it be thought of as an endorsement. ;D
  – J. M. is somewhat okay.♦
  1 hour ago
  

  
  
  
  

add a comment | 

up vote
4
down vote

favorite

Say a list is given as

list = a, b, c, d, r, m, n;

Suppose I want to insert 2 and 3 at position 3 and 7, respectively.

Insert[list, 2, 3] puts 2 at position 3, but Insert[list, 2, 3, 3, 7] does nothing.

How is it possible?

list-manipulation

share|improve this question

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

asked 3 hours ago

Soumyajit Roy

1358

• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  Dirty trick: Block[k = 0, Insert[a, b, c, d, r, m, n, Unevaluated[2, 3[[++k]]], 3, 7]]
  – J. M. is somewhat okay.♦
  3 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @J.M. Wow, that one is really dirty. I had to read it several times to understand it half way at least...
  – Henrik Schumacher
  1 hour ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @Henrik, I didn't want to post it as an answer lest it be thought of as an endorsement. ;D
  – J. M. is somewhat okay.♦
  1 hour ago
  

  
  
  
  

add a comment | 

up vote
4
down vote

favorite

up vote
4
down vote

favorite

Say a list is given as

list = a, b, c, d, r, m, n;

Suppose I want to insert 2 and 3 at position 3 and 7, respectively.

Insert[list, 2, 3] puts 2 at position 3, but Insert[list, 2, 3, 3, 7] does nothing.

How is it possible?

list-manipulation

share|improve this question

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

asked 3 hours ago

Soumyajit Roy

1358

Say a list is given as

list = a, b, c, d, r, m, n;

Suppose I want to insert 2 and 3 at position 3 and 7, respectively.

Insert[list, 2, 3] puts 2 at position 3, but Insert[list, 2, 3, 3, 7] does nothing.

How is it possible?

list-manipulation

list-manipulation

share|improve this question

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

asked 3 hours ago

Soumyajit Roy

1358

share|improve this question

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

asked 3 hours ago

Soumyajit Roy

1358

share|improve this question

share|improve this question

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

edited 1 hour ago

Αλέξανδρος Ζεγγ

2,204725

2,204725

asked 3 hours ago

Soumyajit Roy

1358

asked 3 hours ago

Soumyajit Roy

1358

asked 3 hours ago

Soumyajit Roy

1358

1358

• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  Dirty trick: Block[k = 0, Insert[a, b, c, d, r, m, n, Unevaluated[2, 3[[++k]]], 3, 7]]
  – J. M. is somewhat okay.♦
  3 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @J.M. Wow, that one is really dirty. I had to read it several times to understand it half way at least...
  – Henrik Schumacher
  1 hour ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @Henrik, I didn't want to post it as an answer lest it be thought of as an endorsement. ;D
  – J. M. is somewhat okay.♦
  1 hour ago
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  Dirty trick: Block[k = 0, Insert[a, b, c, d, r, m, n, Unevaluated[2, 3[[++k]]], 3, 7]]
  – J. M. is somewhat okay.♦
  3 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @J.M. Wow, that one is really dirty. I had to read it several times to understand it half way at least...
  – Henrik Schumacher
  1 hour ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @Henrik, I didn't want to post it as an answer lest it be thought of as an endorsement. ;D
  – J. M. is somewhat okay.♦
  1 hour ago
  

  
  
  
  

2

2

Dirty trick: Block[k = 0, Insert[a, b, c, d, r, m, n, Unevaluated[2, 3[[++k]]], 3, 7]]
– J. M. is somewhat okay.♦
3 hours ago

Dirty trick: Block[k = 0, Insert[a, b, c, d, r, m, n, Unevaluated[2, 3[[++k]]], 3, 7]]
– J. M. is somewhat okay.♦
3 hours ago

@J.M. Wow, that one is really dirty. I had to read it several times to understand it half way at least...
– Henrik Schumacher
1 hour ago

@J.M. Wow, that one is really dirty. I had to read it several times to understand it half way at least...
– Henrik Schumacher
1 hour ago

@Henrik, I didn't want to post it as an answer lest it be thought of as an endorsement. ;D
– J. M. is somewhat okay.♦
1 hour ago

@Henrik, I didn't want to post it as an answer lest it be thought of as an endorsement. ;D
– J. M. is somewhat okay.♦
1 hour ago

add a comment | 

3 Answers
3

active

oldest

votes

up vote
4
down vote

How about this

myInsert[list_, valuePosList_] := Fold[Insert[#, Sequence @@ #2] &, 
 list, 
 SortBy[valuePosList, -Last[#] &]
 ]

myInsert[list, 2, 3, 3, 7]

a, b, 2, c, d, r, m, 3, n

share|improve this answer

edited 2 hours ago

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

add a comment | 

up vote
1
down vote

Look what I found after spelunking:

GroupTheory`PermutationGroups`Private`FoldInsert[
 a, b, c, d, r, m, n,
 2, 3, 3, 7
 ]

a, b, 2, c, d, r, 3, m, n

Well, it is not entirely correct for it does not revert the order of insertion... =/

share|improve this answer

answered 1 hour ago

Henrik Schumacher

39.6k254118

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Anyway, wow! (IOU one upvote.)
  – J. M. is somewhat okay.♦
  1 hour ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  I wonder if this package has similar functions.
  – Î‘λέξανδρος Ζεγγ
  46 mins ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
  – Henrik Schumacher
  36 mins ago
  
  

  
  
  
  

add a comment | 

up vote
0
down vote

insertList[list_, valuePosList_] := ReplacePart[
 list,
 Apply[
 Rule[#2, Sequence[#1, list[[#2]]]] &,
 valuePosList
 , 1
 ]
 ]

share

answered 7 mins ago

rhermans

21.6k439104

add a comment | 

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3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

active

oldest

votes

active

oldest

votes

up vote
4
down vote

How about this

myInsert[list_, valuePosList_] := Fold[Insert[#, Sequence @@ #2] &, 
 list, 
 SortBy[valuePosList, -Last[#] &]
 ]

myInsert[list, 2, 3, 3, 7]

a, b, 2, c, d, r, m, 3, n

share|improve this answer

edited 2 hours ago

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

add a comment | 

up vote
4
down vote

How about this

myInsert[list_, valuePosList_] := Fold[Insert[#, Sequence @@ #2] &, 
 list, 
 SortBy[valuePosList, -Last[#] &]
 ]

myInsert[list, 2, 3, 3, 7]

a, b, 2, c, d, r, m, 3, n

share|improve this answer

edited 2 hours ago

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

add a comment | 

up vote
4
down vote

up vote
4
down vote

How about this

myInsert[list_, valuePosList_] := Fold[Insert[#, Sequence @@ #2] &, 
 list, 
 SortBy[valuePosList, -Last[#] &]
 ]

myInsert[list, 2, 3, 3, 7]

a, b, 2, c, d, r, m, 3, n

share|improve this answer

edited 2 hours ago

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

How about this

myInsert[list_, valuePosList_] := Fold[Insert[#, Sequence @@ #2] &, 
 list, 
 SortBy[valuePosList, -Last[#] &]
 ]

myInsert[list, 2, 3, 3, 7]

a, b, 2, c, d, r, m, 3, n

share|improve this answer

edited 2 hours ago

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

share|improve this answer

share|improve this answer

edited 2 hours ago

edited 2 hours ago

edited 2 hours ago

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

answered 2 hours ago

Αλέξανδρος Ζεγγ

2,204725

2,204725

add a comment | 

add a comment | 

up vote
1
down vote

Look what I found after spelunking:

GroupTheory`PermutationGroups`Private`FoldInsert[
 a, b, c, d, r, m, n,
 2, 3, 3, 7
 ]

a, b, 2, c, d, r, 3, m, n

Well, it is not entirely correct for it does not revert the order of insertion... =/

share|improve this answer

answered 1 hour ago

Henrik Schumacher

39.6k254118

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Anyway, wow! (IOU one upvote.)
  – J. M. is somewhat okay.♦
  1 hour ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  I wonder if this package has similar functions.
  – Î‘λέξανδρος Ζεγγ
  46 mins ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
  – Henrik Schumacher
  36 mins ago
  
  

  
  
  
  

add a comment | 

up vote
1
down vote

Look what I found after spelunking:

GroupTheory`PermutationGroups`Private`FoldInsert[
 a, b, c, d, r, m, n,
 2, 3, 3, 7
 ]

a, b, 2, c, d, r, 3, m, n

Well, it is not entirely correct for it does not revert the order of insertion... =/

share|improve this answer

answered 1 hour ago

Henrik Schumacher

39.6k254118

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Anyway, wow! (IOU one upvote.)
  – J. M. is somewhat okay.♦
  1 hour ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  I wonder if this package has similar functions.
  – Î‘λέξανδρος Ζεγγ
  46 mins ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
  – Henrik Schumacher
  36 mins ago
  
  

  
  
  
  

add a comment | 

up vote
1
down vote

up vote
1
down vote

Look what I found after spelunking:

GroupTheory`PermutationGroups`Private`FoldInsert[
 a, b, c, d, r, m, n,
 2, 3, 3, 7
 ]

a, b, 2, c, d, r, 3, m, n

Well, it is not entirely correct for it does not revert the order of insertion... =/

share|improve this answer

answered 1 hour ago

Henrik Schumacher

39.6k254118

Look what I found after spelunking:

GroupTheory`PermutationGroups`Private`FoldInsert[
 a, b, c, d, r, m, n,
 2, 3, 3, 7
 ]

a, b, 2, c, d, r, 3, m, n

Well, it is not entirely correct for it does not revert the order of insertion... =/

share|improve this answer

answered 1 hour ago

Henrik Schumacher

39.6k254118

share|improve this answer

share|improve this answer

answered 1 hour ago

Henrik Schumacher

39.6k254118

answered 1 hour ago

Henrik Schumacher

39.6k254118

answered 1 hour ago

Henrik Schumacher

39.6k254118

39.6k254118

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Anyway, wow! (IOU one upvote.)
  – J. M. is somewhat okay.♦
  1 hour ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  I wonder if this package has similar functions.
  – Î‘λέξανδρος Ζεγγ
  46 mins ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
  – Henrik Schumacher
  36 mins ago
  
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Anyway, wow! (IOU one upvote.)
  – J. M. is somewhat okay.♦
  1 hour ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  I wonder if this package has similar functions.
  – Î‘λέξανδρος Ζεγγ
  46 mins ago
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
  – Henrik Schumacher
  36 mins ago
  
  

  
  
  
  

Anyway, wow! (IOU one upvote.)
– J. M. is somewhat okay.♦
1 hour ago

Anyway, wow! (IOU one upvote.)
– J. M. is somewhat okay.♦
1 hour ago

I wonder if this package has similar functions.
– Î‘λέξανδρος Ζεγγ
46 mins ago

I wonder if this package has similar functions.
– Î‘λέξανδρος Ζεγγ
46 mins ago

@ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
– Henrik Schumacher
36 mins ago

@ΑλέξανδροςΖεγγ That package appears to be very new. Good to know! (... although I won't find it applicable to my own work...)
– Henrik Schumacher
36 mins ago

add a comment | 

up vote
0
down vote

insertList[list_, valuePosList_] := ReplacePart[
 list,
 Apply[
 Rule[#2, Sequence[#1, list[[#2]]]] &,
 valuePosList
 , 1
 ]
 ]

share

answered 7 mins ago

rhermans

21.6k439104

add a comment | 

up vote
0
down vote

insertList[list_, valuePosList_] := ReplacePart[
 list,
 Apply[
 Rule[#2, Sequence[#1, list[[#2]]]] &,
 valuePosList
 , 1
 ]
 ]

share

answered 7 mins ago

rhermans

21.6k439104

add a comment | 

up vote
0
down vote

up vote
0
down vote

insertList[list_, valuePosList_] := ReplacePart[
 list,
 Apply[
 Rule[#2, Sequence[#1, list[[#2]]]] &,
 valuePosList
 , 1
 ]
 ]

share

answered 7 mins ago

rhermans

21.6k439104

insertList[list_, valuePosList_] := ReplacePart[
 list,
 Apply[
 Rule[#2, Sequence[#1, list[[#2]]]] &,
 valuePosList
 , 1
 ]
 ]

share

answered 7 mins ago

rhermans

21.6k439104

share

share

answered 7 mins ago

rhermans

21.6k439104

answered 7 mins ago

rhermans

21.6k439104

answered 7 mins ago

rhermans

21.6k439104

21.6k439104

add a comment | 

add a comment | 

 

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