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Asked by Craig on 16 Sep 2013

Hi all,

I have a cell (1 by X) containing various other cells of letters. I would like to create a loop (X is a variable) which "extracts" each cell from the main cell AND converts it to a double. Can this be done?

Having issues achieving this as MATLAB doesn't seem to enjoy working with letters!

Craig

[EDITED, Jan, copied from comment section]

X= {{'AB';'AC';'AE':'AD'},{'ABC';'ACD'},{'ABED';'ABCD';'AEFD';'ADFG'},{'ABCDEFG'}};

I want to extract all cells from X and convert each to a double.

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Answer by Sean de Wolski on 16 Sep 2013

So:

cellfun(@str2double,{{'1','3','34'},{'45'},{'12','1017'}},'uni',false)

Show 2 older comments

Sean de Wolski on 17 Sep 2013

How do you convert an 'A' to a double? Do you want the ASCII version of it?

Craig on 17 Sep 2013

That is currently what I am thinking I will have to do. Not sure how to convert a whole cell to ascii values though.

Sean de Wolski on 17 Sep 2013

double('A')

Rather than string to double which interprets the *value* not the *ascii*. What is your big picture here, what are you trying to do?

Answer by Jan Simon on 17 Sep 2013

Edited by Jan Simon on 17 Sep 2013

'A' cannot be converted to a double, because it is a letter. The same matters your 'AB', 'ABC', etc also. So please explain, what you expect as output.

You have recognized this problem already: "MATLAB doesn't seem to enjoy working with letters". But as long as such operations are not defined, how could we or Matlab know, what you are trying to do?

Show 1 older comment

Jan Simon on 17 Sep 2013

I still do not understand, what you want to achieve. How does your "{AB; AD ...}" look in Matlab syntax? Here "AB" are not two letters but the name of a variable. What does this mean:

...remove the ones where BOTH letters in each row above (in X) exist.

? What is the relation to the conversion to doubles?

Craig on 17 Sep 2013

Say I have, x=

'A' 'B' 'D' 'A' 'B' 'E' 'A' 'B' 'F' 'A' 'B' 'G' 'A' 'B' 'H' 'A' 'B' 'I' 'A' 'B' 'J' 'A' 'B' 'K' 'A' 'B' 'L' 'A' 'B' 'M' 'A' 'C' 'D' 'A' 'C' 'E'

And pairs of letters, y=

'A' 'C' 'E' 'D' 'E' 'C' 'J' 'I' 'J' 'H' 'M' 'L' 'V' 'T' 'V' 'U' 'Q' 'N' 'Q' 'O' 'Q' 'P'

So I want to loop through each row of y with x so it returns a "new x" =

'A' 'B' 'D' 'A' 'B' 'E' 'A' 'B' 'F' 'A' 'B' 'G' 'A' 'B' 'H' 'A' 'B' 'I' 'A' 'B' 'J' 'A' 'B' 'K' 'A' 'B' 'L' 'A' 'B' 'M'

Where some rows have been removed as they contain both letters contained in any row of y.

Thanks for helping out. It is hard to explain.

Jan Simon on 17 Sep 2013

This is still not valid Matlab syntax:

x= 'A' 'B' 'D' 'A' 'B' 'E' ...

The details matter. So please post code, which we can run by copy&paste.

In "new x" (better use a valid Matlab name here also) the contents of "x" has been modified and some rows are removed. But there is an infinite number of possible algorithms to convert "x" to "new x". Then it is not clear, if you have managed to solve the procedure shown in the comment or if this belongs to the problem.

The only line of code or sentence I understand from your question yet is:

X = {{'AB';'AC';'AE':'AD'},{'ABC';'ACD'},{'ABED';'ABCD';'AEFD';'ADFG'},{'ABCDEFG'}};

Unfortunately I do not see any relation to e.g. your above comment or the text of the original question.

Craig, I know problems are hard to explain. It seems like the the level of abstraction is too high to allow a clear explanation. So try to solve the problem from another direction: Explain the actual problem you want to solve by this method.

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