--- a
+++ b/inst/int2aa.m
@@ -0,0 +1,38 @@
+## Copyright (C) 2008 Bill Denney
+##
+## This software is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## This software is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this software; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{sequencechar} =} int2aa (@var{sequenceint})
+## Convert amino acid integers into characters.  See @code{aminolookup}
+## for the listing of numbers and their corresponding characters.
+## @seealso{aminolookup,aa2int,int2nt,nt2int}
+## @end deftypefn
+
+## Author: Bill Denney <bill@denney.ws>
+
+function seqc = int2aa (seqi)
+
+  if (! isnumeric (seqi))
+    print_usage ();
+  endif
+  sequences = aminolookup ("code", []);
+  seqc = reshape (sequences(seqi), size (seqi));
+endfunction
+
+## Tests
+%!assert (int2aa (1), "A")
+%!assert (int2aa ([1 2]), "AR");
+%!assert (int2aa ([1;2]), ["A";"R"])