file_name_sequence, a MATLAB code which demonstrates ways of generating a sequence of file names with an embedded index that increases.
There are situations such as animations or parallel processing in which it is necessary to generate a sequence of file names which include an embedded index that increases. A simple example might be
        'fred0.txt', 'fred1.txt', 'fred2.txt'
      
      A side issue arises when the number of files is large enough that the
      number of digits in the index will vary.  Thus, if we are going to have
      15 files, do we want to number them as
      
        'fred00.txt' through 'fred14.txt'
      
      which means, for one thing, that they will alphabetize properly, or
      will we be satisfied with
      
        'fred0.txt' through 'fred14.txt' ?
      
      Schemes for generating such a sequence in MATLAB can involve the
      num2str() function, the sprintf() function, or a more elaborate function
      called file_name_inc() which searches a string for embedded numeric
      data and increments it.
    
    The information on this web page is distributed under the MIT license.
file_name_sequence is available in a C version and a C++ version and a Fortran77 version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
filum, a MATLAB code which works with information in text files.