# Convert from cell of a table to an array

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Cameron Dyson on 30 Oct 2020
Commented: Cameron Dyson on 30 Oct 2020
I am importing data from an excel spreadsheet as follows:
Some of the excel cells contain descitions of arrays like "[1,2,3]". The cell from readtable would then be:
{'[1,2,3]'}
I would like to convert this to an array of doubles like
[1,2,3]
How can I go about doing this?

Sindar on 30 Oct 2020
Edited: Sindar on 30 Oct 2020
It gets tricky with different variable types and widths, but hopefully this helps. Worst case, you build up the new table element by element:
% build example like your table
t=table();
t{1,1}={'[1,2,3]'};
t{1,2}={'[4,5,6,7]'}
t =
1×2 table
Var1 Var2
___________ ___________
{'[1,2,3]'} {'[4,5,6,7]'}
% start a new table
t2=table();
% convert the text in the cell to an array:
t2{1,1}=str2num(t{1,1}{1});
t2{1,2}=str2num(t{1,2}{1})
t2 =
1×2 table
Var1 Var2
___________ ________________
1 2 3 4 5 6 7

Sindar on 30 Oct 2020
FYI: if a table has arrays as elements, they need to be the same width down columns. This will error:
t=table()
t{1,1}={'[1,2,3]'}
t{2,1}={'[4,5,6,7]'}
t2=table()
t2{1,1}=str2num(t{1,1}{1})
t2{2,1}=str2num(t{2,1}{1})
Cameron Dyson on 30 Oct 2020
Thank you, its working for me now!

R2020b

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