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How to remove from the data the rows of with fixed number of elements?

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3

$begingroup$

Consider the data which has the form

data = {{x1,y1,z1},{x2,y2,z2,t2},{x3,y4,z4,t4},{x5,y5,z5},...}

How to remove the rows containing three elements from the data?

I.e., to obtain

dataprime = {{x2,y2,z2,t2},{x3,y4,z4,t4},...}

data filtering

share|improve this question

edited 4 hours ago

John Taylor

asked 4 hours ago

John TaylorJohn Taylor

736211

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Maybe you ask for DeleteCases[data, _?(Length[#] == 3 &)]...
  $endgroup$
  – Henrik Schumacher
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @HenrikSchumacher : sorry, already corrected this.
  $endgroup$
  – John Taylor
  4 hours ago
  

  
  
  
  

add a comment | 

3

$begingroup$

Consider the data which has the form

data = {{x1,y1,z1},{x2,y2,z2,t2},{x3,y4,z4,t4},{x5,y5,z5},...}

How to remove the rows containing three elements from the data?

I.e., to obtain

dataprime = {{x2,y2,z2,t2},{x3,y4,z4,t4},...}

data filtering

share|improve this question

edited 4 hours ago

John Taylor

asked 4 hours ago

John TaylorJohn Taylor

736211

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Maybe you ask for DeleteCases[data, _?(Length[#] == 3 &)]...
  $endgroup$
  – Henrik Schumacher
  4 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @HenrikSchumacher : sorry, already corrected this.
  $endgroup$
  – John Taylor
  4 hours ago
  

  
  
  
  

add a comment | 

$begingroup$

Consider the data which has the form

data = {{x1,y1,z1},{x2,y2,z2,t2},{x3,y4,z4,t4},{x5,y5,z5},...}

How to remove the rows containing three elements from the data?

I.e., to obtain

dataprime = {{x2,y2,z2,t2},{x3,y4,z4,t4},...}

data filtering

share|improve this question

edited 4 hours ago

John Taylor

asked 4 hours ago

John TaylorJohn Taylor

736211

$endgroup$

data = {{x1,y1,z1},{x2,y2,z2,t2},{x3,y4,z4,t4},{x5,y5,z5},...}

dataprime = {{x2,y2,z2,t2},{x3,y4,z4,t4},...}

share|improve this question

edited 4 hours ago

John Taylor

asked 4 hours ago

John TaylorJohn Taylor

736211

share|improve this question

edited 4 hours ago

John Taylor

asked 4 hours ago

John TaylorJohn Taylor

736211

asked 4 hours ago

John TaylorJohn Taylor

736211

asked 4 hours ago

John TaylorJohn Taylor

736211

2 Answers
2

active

oldest

votes

4

$begingroup$

Any one of these would do:

Cases[data, Except[_?(Length[#] == 3 &)]]

DeleteCases[data, _?(Length[#] == 3 &)]



Select[data, Length[#] != 3 &]



Delete[data, Position[data, _?(Length[#] == 3 &)]]



data /. {_, _, _} -> Nothing

data /. {Repeated[_, {3}]} -> Nothing

They all return: {{x2, y2, z2, t2}, {x3, y4, z4, t4}}

share|improve this answer

edited 3 hours ago

answered 4 hours ago

MarcoBMarcoB

36.3k556112

$endgroup$

add a comment | 

2

$begingroup$

Also

Pick[data, Unitize[-3 + Length /@ data], 1]

share|improve this answer

answered 4 hours ago

kglrkglr

186k10202421

$endgroup$

add a comment | 

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4

$begingroup$

Any one of these would do:

Cases[data, Except[_?(Length[#] == 3 &)]]

DeleteCases[data, _?(Length[#] == 3 &)]



Select[data, Length[#] != 3 &]



Delete[data, Position[data, _?(Length[#] == 3 &)]]



data /. {_, _, _} -> Nothing

data /. {Repeated[_, {3}]} -> Nothing

They all return: {{x2, y2, z2, t2}, {x3, y4, z4, t4}}

share|improve this answer

edited 3 hours ago

answered 4 hours ago

MarcoBMarcoB

36.3k556112

$endgroup$

add a comment | 

4

$begingroup$

Any one of these would do:

Cases[data, Except[_?(Length[#] == 3 &)]]

DeleteCases[data, _?(Length[#] == 3 &)]



Select[data, Length[#] != 3 &]



Delete[data, Position[data, _?(Length[#] == 3 &)]]



data /. {_, _, _} -> Nothing

data /. {Repeated[_, {3}]} -> Nothing

They all return: {{x2, y2, z2, t2}, {x3, y4, z4, t4}}

share|improve this answer

edited 3 hours ago

answered 4 hours ago

MarcoBMarcoB

36.3k556112

$endgroup$

add a comment | 

$begingroup$

Any one of these would do:

Cases[data, Except[_?(Length[#] == 3 &)]]

DeleteCases[data, _?(Length[#] == 3 &)]



Select[data, Length[#] != 3 &]



Delete[data, Position[data, _?(Length[#] == 3 &)]]



data /. {_, _, _} -> Nothing

data /. {Repeated[_, {3}]} -> Nothing

They all return: {{x2, y2, z2, t2}, {x3, y4, z4, t4}}

share|improve this answer

edited 3 hours ago

answered 4 hours ago

MarcoBMarcoB

36.3k556112

$endgroup$

Cases[data, Except[_?(Length[#] == 3 &)]]

DeleteCases[data, _?(Length[#] == 3 &)]



Select[data, Length[#] != 3 &]



Delete[data, Position[data, _?(Length[#] == 3 &)]]



data /. {_, _, _} -> Nothing

data /. {Repeated[_, {3}]} -> Nothing

share|improve this answer

edited 3 hours ago

answered 4 hours ago

MarcoBMarcoB

36.3k556112

answered 4 hours ago

MarcoBMarcoB

36.3k556112

answered 4 hours ago

MarcoBMarcoB

36.3k556112

2

$begingroup$

Also

Pick[data, Unitize[-3 + Length /@ data], 1]

share|improve this answer

answered 4 hours ago

kglrkglr

186k10202421

$endgroup$

add a comment | 

2

$begingroup$

Also

Pick[data, Unitize[-3 + Length /@ data], 1]

share|improve this answer

answered 4 hours ago

kglrkglr

186k10202421

$endgroup$

add a comment | 

$begingroup$

Also

Pick[data, Unitize[-3 + Length /@ data], 1]

share|improve this answer

answered 4 hours ago

kglrkglr

186k10202421

$endgroup$

Pick[data, Unitize[-3 + Length /@ data], 1]

share|improve this answer

answered 4 hours ago

kglrkglr

186k10202421

answered 4 hours ago

kglrkglr

186k10202421

answered 4 hours ago

kglrkglr

186k10202421