Convert from cell of a table to an array

I am importing data from an excel spreadsheet as follows:

options = readtable('options.xlsx');

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?

Answer 1

[Sindar]

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]

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]

Thank you, its working for me now!