Eliminating duplicate columns in a table when appending

13 vues (au cours des 30 derniers jours)
Danielle Leblance
Danielle Leblance le 5 Fév 2017
Commenté : nikhilthoppil le 10 Avr 2020
Hi,
I am importing data using readtable function. but when i append data using:
mytable=[mytable mytable2];
I receive an error: Duplicate variable name: 'ID' because every file contains the ID of the firm. I need the column ID only once. so how can i skip the ID column in mytable2 when i want to append?

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the cyclist
the cyclist le 5 Fév 2017
Modifié(e) : the cyclist le 5 Fév 2017
Use the join command. Here's a simple example.
% Set up some sample data
id = [1 2 3]';
firstName = {'Walter','Image','Star'}';
lastName = {'Roberson','Analyst','Strider'}';
tableFirst = table(id,firstName);
tableLast = table(id,lastName);
% Join the tables
tableFirstAndLast = join(tableFirst,tableLast)
FYI, there are many input options that govern how the variables in the two tables are retained when there are duplicates, so I suggest carefully reading the documentation (linked above) if this example doesn't do exactly what you want in your case.
You might also need a different function from that family, e.g. innerjoin.
  6 commentaires
the cyclist
the cyclist le 5 Fév 2017
The proximate cause is that some of the tables contain a row with NaN as the value of IDRSSD. Because one NaN is not equal to another NaN, MATLAB cannot join those rows.
One simple solution might be to replace those values of NaN with some other unique identifier. (It looks like setting IDRSSD=0 would work.)
You could also use the innerjoin() function, as I mentioned earlier, which will only use matching rows.
a2=innerjoin(t7,t8);
Or you could manually avoid that first row for those tables:
a2 = join(t7(2:end,:),t8(2:end,:))
but that seems pretty inelegant.
The approach to take will depend on exactly what output you want, and what is more readable and efficient.
nikhilthoppil
nikhilthoppil le 10 Avr 2020
Can I use this function if I need to erge two tables having more that one columns in common?

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