//  wrapper for getresidue(), but intercepts call to convert Brookhaven
//     one-letter residue names to three-letter code

residue	getres( string r, string rlib )
{
	residue	res;
	string map1to3[ hashed ];          // convert residue names

	map1to3["A"] = "ADE";
	map1to3["C"] = "CYT";
	map1to3["G"] = "GUA";
	map1to3["T"] = "THY";
	map1to3["U"] = "URA";

	map1to3["a"] = "ADE";
	map1to3["c"] = "CYT";
	map1to3["g"] = "GUA";
	map1to3["t"] = "THY";
	map1to3["u"] = "URA";

	if( r in map1to3 ) {
		res = getresidue( map1to3[ r ], rlib );
	}else{
		fprintf( stderr, "undefined residue \"%s\"\n", r );
		exit( 1 );
	}
	return( res );
};