different behaviour when concatenating table colums
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The two lines behave differently:
tmp = [all_table.('SpO2_FiO2');myTable.('SpO2_FiO2')]; % this works
tmp = [all_table(:,52);myTable(:,52)]; % this gives error 'Cannot concatenate the table variable 'SpO2_FiO2' because it is a cell in one table and a non-cell in another.'
52 is the column index to the column named ''SpO2_FiO2". The type of this column is double in both tables, all_table and my_Table.
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Answers (1)
Voss
on 23 Dec 2021
If both tables' SpO2_FiO2 columns are actually doubles, then both ways of concatenating do the same thing:
SpO2_FiO2 = (1:3).';
all_table = table(SpO2_FiO2)
myTable = table(SpO2_FiO2)
tmp = [all_table.('SpO2_FiO2');myTable.('SpO2_FiO2')]
tmp = [all_table(:,1);myTable(:,1)]
If instead one table's SpO2_FiO2 column is a cell array, then you get behavior consistent with what you observe:
SpO2_FiO2 = (1:3).';
all_table = table(SpO2_FiO2)
SpO2_FiO2 = num2cell(SpO2_FiO2);
myTable = table(SpO2_FiO2)
tmp = [all_table.('SpO2_FiO2');myTable.('SpO2_FiO2')]
tmp = [all_table(:,1);myTable(:,1)]
In the second case, the line:
tmp = [all_table.('SpO2_FiO2');myTable.('SpO2_FiO2')];
does not generate an error, but it doesn't necessarily 'work' because it doesn't necessarily do what you want. It gives a 4-by-1 cell array where the first element is a 3-by-1 vector of doubles and the 2nd, 3rd, and 4th elements are all scalar doubles, as opposed to a 6-by-1 vector of doubles, which is what you get either way you do the concatenation when both columns are actually doubles.
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