iFit/read

 Read d4d object from a file or array of d4d objects from a set of files
 
   >> w=read(d4d,file)

 Need to give first argument as an d4d object to enforce a call to this function.
 Can simply create a dummy object with a call to d4d:
    e.g. >> w = read(d4d,'c:\temp\my_file.d4d')

 Input:
 -----
   d4d         Dummy d4d object to enforce the execution of this method.
               Can simply create a dummy object with a call to d4d:
                   e.g. >> w = read(d4d,'c:\temp\my_file.d4d')

   file        File name, or cell array of file names. In this case, reads
               into an array of d4d objects

 Output:
 -------
   w           d4d object, or array of d4d objects if given cell array of
               file names