Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help match_val”.

  MATCH_VAL looks for matching values in two arrays of values
  and returns the indices into both the 1st and 2nd list of the matches.
  They will be ordered according to the first input argument.
 
  Use as
    [sel1, sel2] = match_str(vallist1, vallist2)
 
  See also MATCH_STR