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How to check whether a column exist in a table?

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Alon Rozen
Alon Rozen am 24 Nov. 2016
Hi all,
I search for this question in the web and found the following solution: Suppose I have a table named 'My_Table' and want to check if it contains a column (field) named 'My_Column'. The code:
Exist_Column = strmatch('My_Column',My_Table.Properties.VariableNames)
should result in logical that answer the question. I checked it and it works. However, the Matlab editor commented that 'strmatch' is not a recommended function to use because it is about to be removed in future version and suggest instead the use of either 'strncmp' or 'validatestring'. Problem is that both do not return a logical and more steps are required to get the answer.
So, my question is: what is the simplest recommended way to determine if a certain column name exist in a table?
Thanks,
Alon
  1 Kommentar
Carlos Aguilar
Carlos Aguilar am 31 Dez. 2017
Just came across to this question. An anonymous function will also do the job (and will be reusable within the scope):
isTableCol = @(t, thisCol) ismember(thisCol, t.Properties.VariableNames);

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Akzeptierte Antwort

KSSV
KSSV am 24 Nov. 2016
Exist_Column = strcmp('My_Column',My_Table.Properties.VariableNames)
val = Exist_Column(Exist_Column==1) ;
  6 Kommentare
Gabriel Blanco
Gabriel Blanco am 25 Jun. 2019
Bonjour Nic!
Nikolaus Koopmann
Nikolaus Koopmann am 29 Nov. 2022
any("MyColumn" == string(My_Table.Properties.VariableNames))

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Weitere Antworten (2)

jkr
jkr am 14 Mai 2019
sum(ismember(mx.Properties.VariableNames,'NameYouWantToCheck'))
returns 1 if found, 0 if not
  2 Kommentare
AusPollen
AusPollen am 23 Mai 2021
Nice! although you don't need to sum if you switch the ismember arguments, ie. use ismember('My_Column',My_Table.Properties.VariableNames)
Nachiket Wadwankar
Nachiket Wadwankar am 9 Feb. 2024
This is exactly what I wanted. Thanks a lot for this trick!!

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Sean Lynch
Sean Lynch am 5 Sep. 2021
I used "any", but agree "ismember" is even better
exists = any(strcmp('Column-Name', My_Table.Properties.VariableNames))

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