Convert a cell column of strings to doubles

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I have a cell column of strings which looks like the attached file. How can I convert the column to double-precision values?
  1 Comment
Stephen23
Stephen23 on 15 Jul 2015
Please try attaching your data again. Press then parperclip button, then both the Choose file and Attach file buttons.

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Accepted Answer

Star Strider
Star Strider on 15 Jul 2015
See if this does what you want:
D = load('string_column.mat');
data = D.owner;
out = cellfun(@(x) str2num(char(x)), data);
  2 Comments
Eli Dim
Eli Dim on 15 Jul 2015
Thank you very much, I understand now what the problem was!

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More Answers (2)

Stephen23
Stephen23 on 15 Jul 2015
Edited: Stephen23 on 15 Jul 2015
If the data is a cell array of strings, then try using str2double:
>> A = {'1.2';'2.3';45.6789';'Inf'};
>> B = str2double(A);
B =
1.2000
2.3000
45.6789
Inf
  3 Comments
Guillaume
Guillaume on 15 Jul 2015
Edited: Guillaume on 15 Jul 2015
The column consists only of numeric values.
No! All but the last four cells of your cell arrays are actually cell arrays themselves.
Stephen23
Stephen23 on 15 Jul 2015
Edited: Stephen23 on 15 Jul 2015
The problem is that data is not a cell array of strings, as you think it is, but actually mostly it is a cell array of cells containing strings, except for the last four cells (which are strings):
>> iscellstr(owner)
ans =
0
>> owner(1:5)
ans =
{1x1 cell}
{1x1 cell}
{1x1 cell}
{1x1 cell}
{1x1 cell}
>> owner(end-6:end)
ans =
{1x1 cell}
{1x1 cell}
{1x1 cell}
'0'
'0'
'0'
'0'
You can solve this as follows:
>> idx = cellfun('isclass',owner,'cell');
>> owner(idx) = [owner{idx}];
>> out = str2double(owner);
>> out(1:5)
ans =
1
2
3
4
5
>> out(end-6:end)
ans =
2300
2301
2302
0
0
0
0
This is the data file that I used:

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Guillaume
Guillaume on 15 Jul 2015
str2double(vertcat(owner{:}))
works, because your each cell of your cell array (except for the last four) is actually itself a cell array which in turn contain the string.
The vertcat above convert your cell array of single cell arrays of strings into a cell array of strings.

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