When creating a table, how do I specify the dimensions of a particular variable?

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Hello all,
Lets say Im defining an empty table as so:
my_table = table('Size', [0,7], 'VariableNames', ...
{'name', 'window', 'fs', ...
'x', 'y', 'z', 'mag'}, ...
'VariableTypes', ...
{'string', 'double', 'double', ...
'double', 'double', 'double', 'double'});
The variable that I want to put in in 'window' is actually a 1x2 double. But when I set it:
my_table.window(1) = [1 4];
I get the error:
Unable to perform assignment because the size of the left side is 1-by-1 and the size of the right side is 1-by-2.
So: how do I specify that my 'window' is actually 1x2?
Many thanks

Accepted Answer

Steven Lord
Steven Lord on 11 Jul 2021
my_table = table('Size', [0,7], 'VariableNames', ...
{'name', 'window', 'fs', ...
'x', 'y', 'z', 'mag'}, ...
'VariableTypes', ...
{'string', 'double', 'double', ...
'double', 'double', 'double', 'double'});
my_table.window(1, 1:2) = [1 4]
Warning: The assignment added rows to the table, but did not assign values to all of the table's existing variables. Those variables are extended with rows containing default values.
my_table = 1×7 table
name window fs x y z mag _________ ______ __ _ _ _ ___ <missing> 1 4 0 0 0 0 0

More Answers (2)

Walter Roberson
Walter Roberson on 11 Jul 2021
Edited: Walter Roberson on 11 Jul 2021
You cannot do that using that construction technique.
See also my answer there.

Sulaymon Eshkabilov
Sulaymon Eshkabilov on 11 Jul 2021
It is better to create a zero matrix and then assign a table variable, e.g.:
Nrows=10; Ncols=8;
A = zeros(10, 8);
my_table = array2table(A, 'VariableNames', {'name', 'win1', 'win2', 'fs','x', 'y', 'z', 'mag'});
%% Assign the values
my_table.win1(1)=1;
my_table.win2(1)=4;
%% Make a new column (var named "window")
my_table.window=[my_table.win1, my_table.win2];
my_table.win1=[];
my_table.win2=[];

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