(octave.info)Cell Arrays of Strings

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6.3.4 Cell Arrays of Strings
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One common use of cell arrays is to store multiple strings in the same
variable.  It is also possible to store multiple strings in a character
matrix by letting each row be a string.  This, however, introduces the
problem that all strings must be of equal length.  Therefore, it is
recommended to use cell arrays to store multiple strings.  For cases,
where the character matrix representation is required for an operation,
there are several functions that convert a cell array of strings to a
character array and back.  ‘char’ and ‘strvcat’ convert cell arrays to a
character array (Note: Concatenating Strings), while the function
‘cellstr’ converts a character array to a cell array of strings:

     a = ["hello"; "world"];
     c = cellstr (a)
          ⇒ c =
              {
                [1,1] = hello
                [2,1] = world
              }

 -- : CSTR = cellstr (STRMAT)
     Create a new cell array object from the elements of the string
     array STRMAT.

     Each row of STRMAT becomes an element of CSTR.  Any trailing spaces
     in a row are deleted before conversion.

     To convert back from a cellstr to a character array use ‘char’.

     See also: Note: cell, Note: char.

   One further advantage of using cell arrays to store multiple strings
is that most functions for string manipulations included with Octave
support this representation.  As an example, it is possible to compare
one string with many others using the ‘strcmp’ function.  If one of the
arguments to this function is a string and the other is a cell array of
strings, each element of the cell array will be compared to the string
argument:

     c = {"hello", "world"};
     strcmp ("hello", c)
          ⇒ ans =
             1   0

The following string functions support cell arrays of strings: ‘char’,
‘strvcat’, ‘strcat’ (Note: Concatenating Strings), ‘strcmp’,
‘strncmp’, ‘strcmpi’, ‘strncmpi’ (Note: Comparing Strings),
‘str2double’, ‘deblank’, ‘strtrim’, ‘strtrunc’, ‘strfind’, ‘strmatch’, ,
‘regexp’, ‘regexpi’ (Note: Manipulating Strings) and ‘str2double’
(Note: String Conversions).

   The function ‘iscellstr’ can be used to test if an object is a cell
array of strings.

 -- : iscellstr (CELL)
     Return true if every element of the cell array CELL is a character
     string.

     See also: Note: ischar, Note: isstring.