===================================================================
RCS file: /home/cvs/OpenXM_contrib2/asir2000/builtin/strobj.c,v
retrieving revision 1.96
retrieving revision 1.113
diff -u -p -r1.96 -r1.113
--- OpenXM_contrib2/asir2000/builtin/strobj.c	2005/11/04 07:03:38	1.96
+++ OpenXM_contrib2/asir2000/builtin/strobj.c	2005/12/18 06:54:28	1.113
@@ -45,7 +45,7 @@
  * DEVELOPER SHALL HAVE NO LIABILITY IN CONNECTION WITH THE USE,
  * PERFORMANCE OR NON-PERFORMANCE OF THE SOFTWARE.
  *
- * $OpenXM: OpenXM_contrib2/asir2000/builtin/strobj.c,v 1.95 2005/11/03 07:41:22 noro Exp $
+ * $OpenXM: OpenXM_contrib2/asir2000/builtin/strobj.c,v 1.112 2005/12/18 01:57:21 noro Exp $
 */
 #include "ca.h"
 #include "parse.h"
@@ -76,6 +76,7 @@ struct TeXSymbol {
 #define IS_BINARYPWR(f) (((f)->id==I_BOP) &&(OPNAME(f)=='^'))
 #define IS_NARYADD(f) (((f)->id==I_NARYOP) &&(OPNAME(f)=='+'))
 #define IS_NARYMUL(f) (((f)->id==I_NARYOP) &&(OPNAME(f)=='*'))
+#define IS_MUL(f) (((f)->id==I_NARYOP||(f)->id==I_BOP) &&(OPNAME(f)=='*'))
 
 extern char *parse_strp;
 
@@ -92,15 +93,25 @@ void Pquotetotex();
 void Pquotetotex_env();
 void Pflatten_quote();
 
-void Pquote_is_integer(),Pquote_is_rational(),Pquote_is_number();
-void Pquote_is_dependent(),Pquote_is_function();
-void Pquote_normalize();
-void Pnquote_comp();
-void Pnquote_match();
+void Pqt_is_integer(),Pqt_is_rational(),Pqt_is_number(),Pqt_is_coef();
+void Pqt_is_dependent(),Pqt_is_function(),Pqt_is_var();
+void Pqt_set_ord(),Pqt_set_coef(),Pqt_set_weight();
+void Pqt_normalize();
+void Pnqt_comp(),Pnqt_weight();
+void Pnqt_match();
+void Pnqt_match_rewrite();
 
+void Pqt_to_nbp();
+void Pshuffle_mul(), Pharmonic_mul();
+void Pnbp_hm(), Pnbp_ht(), Pnbp_hc(), Pnbp_rest();
+void Pnbm_deg();
+void Pnbm_hp_rest();
+void Pnbm_hxky(), Pnbm_xky_rest();
+void Pnbm_hv(), Pnbm_rest();
+
 void Pquote_to_funargs(),Pfunargs_to_quote(),Pget_function_name();
-void Pquote_match(),Pget_quote_id(),Pquote_match_rewrite();
-void Pquote_to_nary(),Pquote_to_bin();
+void Pqt_match(),Pget_quote_id();
+void Pqt_to_nary(),Pqt_to_bin();
 void fnode_do_assign(NODE arg);
 void do_assign(NODE arg);
 void fnodetotex_tb(FNODE f,TB tb);
@@ -112,7 +123,22 @@ void tb_to_string(TB tb,STRING *rp);
 void fnodenodetotex_tb(NODE n,TB tb);
 void fargstotex_tb(char *opname,FNODE f,TB tb);
 int top_is_minus(FNODE f);
-int quote_match(Obj f,Obj pat,NODE *rp);
+int qt_match(Obj f,Obj pat,NODE *rp);
+FNODE partial_eval(FNODE), fnode_to_nary(FNODE), fnode_to_bin(FNODE,int);
+FNODE nfnode_add(FNODE a1,FNODE a2,int expand);
+FNODE nfnode_mul(FNODE a1,FNODE a2,int expand);
+FNODE nfnode_pwr(FNODE a1,FNODE a2,int expand);
+FNODE nfnode_mul_coef(Obj c,FNODE f,int expand);
+FNODE fnode_expand_pwr(FNODE f,int n,int expand);
+FNODE to_narymul(FNODE f);
+FNODE to_naryadd(FNODE f);
+FNODE fnode_node_to_nary(ARF op,NODE n);
+void fnode_base_exp(FNODE f,FNODE *bp,FNODE *ep);
+void fnode_coef_body(FNODE f,Obj *cp,FNODE *bp);
+FNODE nfnode_match_rewrite(FNODE f,FNODE p,FNODE c,FNODE a,int mode);
+FNODE fnode_apply(FNODE f,FNODE (*func)(),int expand);
+FNODE fnode_normalize(FNODE f,int expand);
+FNODE rewrite_fnode(FNODE f,NODE arg,int qarg);
 
 struct ftab str_tab[] = {
 	{"sprintf",Psprintf,-99999999},
@@ -130,21 +156,42 @@ struct ftab str_tab[] = {
 	{"string_to_tb",Pstring_to_tb,1},
 	{"get_quote_id",Pget_quote_id,1},
 
-	{"quote_is_number",Pquote_is_number,1},
-	{"quote_is_rational",Pquote_is_rational,1},
-	{"quote_is_integer",Pquote_is_integer,1},
-	{"quote_is_function",Pquote_is_function,1},
-	{"quote_is_dependent",Pquote_is_dependent,2},
+	{"qt_is_var",Pqt_is_var,1},
+	{"qt_is_coef",Pqt_is_coef,1},
+	{"qt_is_number",Pqt_is_number,1},
+	{"qt_is_rational",Pqt_is_rational,1},
+	{"qt_is_integer",Pqt_is_integer,1},
+	{"qt_is_function",Pqt_is_function,1},
+	{"qt_is_dependent",Pqt_is_dependent,2},
 
-	{"quote_normalize",Pquote_normalize,-2},
-	{"quote_match",Pquote_match,2},
-	{"quote_match_rewrite",Pquote_match_rewrite,-4},
-	{"nquote_comp",Pnquote_comp,2},
-	{"nquote_match",Pnquote_match,2},
+	{"qt_set_coef",Pqt_set_coef,-1},
+	{"qt_set_ord",Pqt_set_ord,-1},
+	{"qt_set_weight",Pqt_set_weight,-1},
+	{"qt_normalize",Pqt_normalize,-2},
+	{"qt_match",Pqt_match,2},
+	{"nqt_match_rewrite",Pnqt_match_rewrite,3},
 
-	{"quote_to_nary",Pquote_to_nary,1},
-	{"quote_to_bin",Pquote_to_bin,2},
+	{"nqt_weight",Pnqt_weight,1},
+	{"nqt_comp",Pnqt_comp,2},
+	{"nqt_match",Pnqt_match,-3},
+	{"qt_to_nbp",Pqt_to_nbp,1},
+	{"shuffle_mul",Pshuffle_mul,2},
+	{"harmonic_mul",Pharmonic_mul,2},
 
+	{"nbp_hm", Pnbp_hm,1},
+	{"nbp_ht", Pnbp_ht,1},
+	{"nbp_hc", Pnbp_hc,1},
+	{"nbp_rest", Pnbp_rest,1},
+	{"nbm_deg", Pnbm_deg,1},
+	{"nbm_hxky", Pnbm_hxky,1},
+	{"nbm_xky_rest", Pnbm_xky_rest,1},
+	{"nbm_hp_rest", Pnbm_hp_rest,1},
+	{"nbm_hv", Pnbm_hv,1},
+	{"nbm_rest", Pnbm_rest,1},
+
+	{"qt_to_nary",Pqt_to_nary,1},
+	{"qt_to_bin",Pqt_to_bin,2},
+
 	{"quotetotex_tb",Pquotetotex_tb,2},
 	{"quotetotex",Pquotetotex,1},
 	{"quotetotex_env",Pquotetotex_env,-99999999},
@@ -547,9 +594,7 @@ void Pwrite_to_tb(NODE arg,Q *rp)
 	*rp = 0;	
 }
 
-FNODE partial_eval(FNODE), fnode_to_nary(FNODE), fnode_to_bin(FNODE,int);
-
-void Pquote_to_nary(NODE arg,QUOTE *rp)
+void Pqt_to_nary(NODE arg,QUOTE *rp)
 {
 	FNODE f;
 
@@ -557,7 +602,7 @@ void Pquote_to_nary(NODE arg,QUOTE *rp)
 	MKQUOTE(*rp,f);	
 }
 
-void Pquote_to_bin(NODE arg,QUOTE *rp)
+void Pqt_to_bin(NODE arg,QUOTE *rp)
 {
 	FNODE f;
 	int direction;
@@ -568,46 +613,68 @@ void Pquote_to_bin(NODE arg,QUOTE *rp)
 	MKQUOTE(*rp,f);	
 }
 
-void Pquote_is_number(NODE arg,Q *rp)
+void Pqt_is_var(NODE arg,Q *rp)
 {
 	QUOTE q;
 	int ret;
 
 	q = (QUOTE)ARG0(arg);
-	asir_assert(q,O_QUOTE,"quote_is_number");
+	asir_assert(q,O_QUOTE,"qt_is_var");
+	ret = fnode_is_var(BDY(q));
+	STOQ(ret,*rp);
+}
+
+void Pqt_is_coef(NODE arg,Q *rp)
+{
+	QUOTE q;
+	int ret;
+
+	q = (QUOTE)ARG0(arg);
+	asir_assert(q,O_QUOTE,"qt_is_coef");
+	ret = fnode_is_coef(BDY(q));
+	STOQ(ret,*rp);
+}
+
+void Pqt_is_number(NODE arg,Q *rp)
+{
+	QUOTE q;
+	int ret;
+
+	q = (QUOTE)ARG0(arg);
+	asir_assert(q,O_QUOTE,"qt_is_number");
 	ret = fnode_is_number(BDY(q));
 	STOQ(ret,*rp);
 }
 
-void Pquote_is_rational(NODE arg,Q *rp)
+void Pqt_is_rational(NODE arg,Q *rp)
 {
 	QUOTE q;
 	int ret;
 
 	q = (QUOTE)ARG0(arg);
-	asir_assert(q,O_QUOTE,"quote_is_rational");
+	asir_assert(q,O_QUOTE,"qt_is_rational");
 	ret = fnode_is_rational(BDY(q));
 	STOQ(ret,*rp);
 }
 
-void Pquote_is_integer(NODE arg,Q *rp)
+void Pqt_is_integer(NODE arg,Q *rp)
 {
 	QUOTE q;
 	int ret;
 
 	q = (QUOTE)ARG0(arg);
-	asir_assert(q,O_QUOTE,"quote_is_integer");
+	asir_assert(q,O_QUOTE,"qt_is_integer");
 	ret = fnode_is_integer(BDY(q));
 	STOQ(ret,*rp);
 }
 
-void Pquote_is_function(NODE arg,Q *rp)
+void Pqt_is_function(NODE arg,Q *rp)
 {
 	QUOTE q;
 	int ret;
 
 	q = (QUOTE)ARG0(arg);
-	asir_assert(q,O_QUOTE,"quote_is_function");
+	asir_assert(q,O_QUOTE,"qt_is_function");
 	if ( q->id == I_FUNC || q->id == I_IFUNC )
 		ret = 1;
 	else
@@ -615,7 +682,7 @@ void Pquote_is_function(NODE arg,Q *rp)
 	STOQ(ret,*rp);
 }
 
-void Pquote_is_dependent(NODE arg,Q *rp)
+void Pqt_is_dependent(NODE arg,Q *rp)
 {
 	P x;
 	QUOTE q,v;
@@ -624,8 +691,8 @@ void Pquote_is_dependent(NODE arg,Q *rp)
 
 	q = (QUOTE)ARG0(arg);
 	v = (QUOTE)ARG1(arg);
-	asir_assert(q,O_QUOTE,"quote_is_dependent");
-	asir_assert(v,O_QUOTE,"quote_is_dependent");
+	asir_assert(q,O_QUOTE,"qt_is_dependent");
+	asir_assert(v,O_QUOTE,"qt_is_dependent");
 	x = (P)eval(BDY(v));
 	if ( !x || OID(x) != O_P )
 		*rp = 0;
@@ -635,7 +702,7 @@ void Pquote_is_dependent(NODE arg,Q *rp)
 }
 
 
-void Pquote_match(NODE arg,Q *rp)
+void Pqt_match(NODE arg,Q *rp)
 {
 	FNODE f,g;
 	Obj obj;
@@ -643,14 +710,8 @@ void Pquote_match(NODE arg,Q *rp)
 	NODE r;
 	int ret;
 
-#if 0
-	g = partial_eval(BDY(((QUOTE)ARG0(arg))));
-	MKQUOTE(q,g);
-	ret = quote_match((Obj)q,(Obj)ARG1(arg),&r);
-#else
 	obj = (Obj)ARG0(arg);
-	ret = quote_match(obj,(Obj)ARG1(arg),&r);
-#endif
+	ret = qt_match(obj,(Obj)ARG1(arg),&r);
 	if ( ret ) {
 		do_assign(r);
 		*rp = ONE;
@@ -658,15 +719,17 @@ void Pquote_match(NODE arg,Q *rp)
 		*rp = 0;
 }
 
-void Pnquote_match(NODE arg,Q *rp)
+void Pnqt_match(NODE arg,Q *rp)
 {
 	QUOTE fq,pq;
 	FNODE f,p;
 	int ret;
+	Q mode;
 	NODE r;
 
-	fq = (QUOTE)ARG0(arg); Pquote_normalize(mknode(2,fq,0),&fq); f = (FNODE)BDY(fq);
-	pq = (QUOTE)ARG1(arg); Pquote_normalize(mknode(2,pq,0),&pq); p = (FNODE)BDY(pq);
+	mode = argc(arg)==3 ? (Q)ARG2(arg) : 0;
+	fq = (QUOTE)ARG0(arg); Pqt_normalize(mknode(2,fq,mode),&fq); f = (FNODE)BDY(fq);
+	pq = (QUOTE)ARG1(arg); Pqt_normalize(mknode(2,pq,mode),&pq); p = (FNODE)BDY(pq);
 	ret = nfnode_match(f,p,&r);
 	if ( ret ) {
 		fnode_do_assign(r);
@@ -675,47 +738,98 @@ void Pnquote_match(NODE arg,Q *rp)
 		*rp = 0;
 }
 
-FNODE rewrite_fnode(FNODE,NODE);
+void Pnqt_match_rewrite(NODE arg,Obj *rp)
+{
+	FNODE f,p,c,a,r;
+	Obj obj,pat,cond,action;
+	NODE rule;
+	QUOTE q;
+	Q mode;
+	int m;
 
-extern Obj VOIDobj;
+	obj = (Obj)ARG0(arg);
+	rule = BDY((LIST)ARG1(arg));
+	mode = (Q)ARG2(arg);
+	if ( length(rule) == 2 ) {
+		pat = ARG0(rule);
+		cond = (Obj)ONE;
+		action = (Obj)ARG1(rule);
+	} else {
+		pat = ARG0(rule);
+		cond = ARG1(rule);
+		action = (Obj)ARG2(rule);
+	}
+	Pqt_normalize(mknode(2,obj,mode),&q); f = (FNODE)BDY(q);
+	Pqt_normalize(mknode(2,pat,mode),&q); p = (FNODE)BDY(q);
+	Pqt_normalize(mknode(2,action,mode),&q);
+	a = (FNODE)BDY(q);
+	if ( OID(cond) == O_QUOTE ) c = BDY((QUOTE)cond);
+	else c = mkfnode(1,I_FORMULA,ONE);
 
-void Pquote_match_rewrite(NODE arg,Obj *rp)
+	m = QTOS(mode);
+	r = nfnode_match_rewrite(f,p,c,a,m);
+	if ( r ) {
+		MKQUOTE(q,r);
+		*rp = (Obj)q;
+	} else
+		*rp = obj;
+}
+
+/* f is NARYOP => do submatch */
+
+#define PV_ANY 99999999
+
+FNODE nfnode_match_rewrite(FNODE f,FNODE p,FNODE c,FNODE a,int mode)
 {
-	FNODE f,g,h,c,value;
-	Obj obj;
+	ARF op;
+	NODE arg,h0,t,h,valuen;
+	NODE r,s0,s,pair;
+	FNODE any,pany,head,tail,a1,a2;
 	QUOTE q;
-	NODE r,t,s,s0,pair;
-	int ret,ind,ac;
+	int ret;
+	FNODE value;
+	int ind;
 
-	obj = (Obj)ARG0(arg);
-	ret = quote_match(obj,(Obj)ARG1(arg),&r);
-	if ( ret ) {
-		for ( t = r, s0 = 0; t; t = NEXT(t) ) {
-			NEXTNODE(s0,s);
-			pair = BDY((LIST)BDY(t));
-			ind = (int)FA0((FNODE)BDY((QUOTE)BDY(pair)));
-			value = BDY((QUOTE)(BDY(NEXT(pair))));
-			BDY(s) = mknode(2,ind,value);
-		}
-		if ( s0 ) NEXT(s) = 0;
-		switch ( ac = argc(arg) ) {
-			case 3:
-				h = rewrite_fnode(BDY((QUOTE)ARG2(arg)),s0);
-				MKQUOTE(q,h); *rp = (Obj)q;
+	if ( f->id == I_NARYOP ) {
+		op = (ARF)FA0(f);
+		arg = (NODE)FA1(f);
+		pany = 0;
+		for ( h0 = 0, t = arg; t; t = NEXT(t) ) {
+			tail = fnode_node_to_nary(op,t);
+			ret = nfnode_match(tail,p,&r) && eval(rewrite_fnode(c,r,1));
+			if ( ret ) break;
+
+			/* append a variable to the pattern */
+			if ( !pany ) {
+				any = mkfnode(1,I_PVAR,PV_ANY);
+				pany = mkfnode(3,I_BOP,op,p,any);
+				pany = fnode_normalize(pany,mode);
+			}
+			ret = nfnode_match(tail,pany,&r) && eval(rewrite_fnode(c,r,1));
+			if ( ret ) {
+				a = fnode_normalize(mkfnode(3,I_BOP,op,a,any),mode);
 				break;
-			case 4:
-				c = rewrite_fnode(BDY((QUOTE)ARG2(arg)),s0);
-				if ( eval(c) ) {
-					h = rewrite_fnode(BDY((QUOTE)ARG3(arg)),s0);
-					MKQUOTE(q,h); *rp = (Obj)q;
-				} else
-					*rp = VOIDobj;
-				break;
-			default:
-				error("quote_match_rewrite : invalid argument");
+			}
+
+			NEXTNODE(h0,h);
+			BDY(h) = BDY(t);
 		}
+		if ( t ) {
+			if ( h0 ) NEXT(h) = 0;
+			head = fnode_node_to_nary(op,h0);
+			a = fnode_normalize(mkfnode(3,I_BOP,op,head,a),mode);
+			ret = 1;
+		} else
+			ret = 0;
 	} else
-		*rp = VOIDobj;
+		ret = nfnode_match(f,p,&r) && eval(rewrite_fnode(c,r,1));
+
+	if ( ret ) {
+		a1 = rewrite_fnode(a,r,0);
+		a2 = partial_eval(a1);
+		return fnode_normalize(a2,mode);
+	} else
+		return 0;
 }
 
 void do_assign(NODE arg)
@@ -792,14 +906,14 @@ int merge_matching_node(NODE n,NODE a,NODE *rp)
 	return 1;
 }
 
-int quote_match_node(NODE f,NODE pat,NODE *rp) {
+int qt_match_node(NODE f,NODE pat,NODE *rp) {
 	NODE r,a,tf,tp,r1;
 	int ret;
 
 	if ( length(f) != length(pat) ) return 0;
 	r = 0;
 	for ( tf = f, tp = pat; tf; tf = NEXT(tf), tp = NEXT(tp) ) {
-		ret = quote_match((Obj)BDY(tf),(Obj)BDY(tp),&a);
+		ret = qt_match((Obj)BDY(tf),(Obj)BDY(tp),&a);
 		if ( !ret ) return 0;
 		ret = merge_matching_node(r,a,&r1);
 		if ( !ret ) return 0;
@@ -811,7 +925,7 @@ int quote_match_node(NODE f,NODE pat,NODE *rp) {
 
 /* f = [a,b,c,...] pat = [X,Y,...] rpat matches the rest of f */
 
-int quote_match_cons(NODE f,NODE pat,Obj rpat,NODE *rp) {
+int qt_match_cons(NODE f,NODE pat,Obj rpat,NODE *rp) {
 	QUOTE q;
 	Q id;
 	FNODE fn;
@@ -823,7 +937,7 @@ int quote_match_cons(NODE f,NODE pat,Obj rpat,NODE *rp
 	if ( length(f) < length(pat) ) return 0;
 	r = 0;
 	for ( tf = f, tp = pat; tp; tf = NEXT(tf), tp = NEXT(tp) ) {
-		ret = quote_match((Obj)BDY(tf),(Obj)BDY(tp),&a);
+		ret = qt_match((Obj)BDY(tf),(Obj)BDY(tp),&a);
 		if ( !ret ) return 0;
 		ret = merge_matching_node(r,a,&r1);
 		if ( !ret ) return 0;
@@ -835,7 +949,7 @@ int quote_match_cons(NODE f,NODE pat,Obj rpat,NODE *rp
 	MKLIST(alist,a);
 	arg = mknode(1,alist);
 	Pfunargs_to_quote(arg,&q);
-	ret = quote_match((Obj)q,rpat,&a);
+	ret = qt_match((Obj)q,rpat,&a);
 	if ( !ret ) return 0;
 	ret = merge_matching_node(r,a,&r1);
 	if ( !ret ) return 0;
@@ -854,7 +968,7 @@ void get_quote_id_arg(QUOTE f,int *id,NODE *r)
 
 /* *rp : [[quote(A),quote(1)],...] */
 
-int quote_match(Obj f, Obj pat, NODE *rp)
+int qt_match(Obj f, Obj pat, NODE *rp)
 {
 	NODE tf,tp,head,body;
 	NODE parg,farg,r;
@@ -873,7 +987,7 @@ int quote_match(Obj f, Obj pat, NODE *rp)
 			return 0;
 	else if ( OID(pat) == O_LIST ) {
 		if ( OID(f) == O_LIST )
-			return quote_match_node(BDY((LIST)f),BDY((LIST)pat),rp);
+			return qt_match_node(BDY((LIST)f),BDY((LIST)pat),rp);
 		else
 			return 0;
 	} else if ( OID(pat) == O_QUOTE ) {
@@ -900,10 +1014,10 @@ int quote_match(Obj f, Obj pat, NODE *rp)
 
 				tp = BDY((LIST)BDY(parg));
 				if ( pid == I_LIST )
-					return quote_match_node(tf,tp,rp);
+					return qt_match_node(tf,tp,rp);
 				else {
 					rpat = (Obj)BDY(NEXT(parg));
-					return quote_match_cons(tf,tp,rpat,rp);
+					return qt_match_cons(tf,tp,rpat,rp);
 				}
 
 			case I_PVAR:
@@ -919,7 +1033,7 @@ int quote_match(Obj f, Obj pat, NODE *rp)
 				if ( id == I_FUNC ) {
 					r = mknode(2,BDY(parg),BDY(farg)); MKLIST(l,r);
 					head = mknode(1,l);
-					ret = quote_match(BDY(NEXT(farg)),
+					ret = qt_match(BDY(NEXT(farg)),
 								BDY(NEXT(parg)),&body);
 					if ( !ret ) return 0;
 					else return merge_matching_node(head,body,rp);
@@ -947,7 +1061,7 @@ int quote_match(Obj f, Obj pat, NODE *rp)
 				get_quote_id_arg((QUOTE)pat,&pid,&parg);
 				get_quote_id_arg((QUOTE)f,&id,&farg);
 				if ( compqa(CO,BDY(farg),BDY(parg)) ) return 0;
-				return quote_match_node(NEXT(farg),NEXT(parg),rp);
+				return qt_match_node(NEXT(farg),NEXT(parg),rp);
 
 			default:
 				if ( OID(f) != O_QUOTE ) return 0;
@@ -955,7 +1069,7 @@ int quote_match(Obj f, Obj pat, NODE *rp)
 				if ( id != pid ) return 0;
 				get_quote_id_arg((QUOTE)pat,&pid,&parg);
 				get_quote_id_arg((QUOTE)f,&id,&farg);
-				return quote_match_node(farg,parg,rp);
+				return qt_match_node(farg,parg,rp);
 		}
 	}
 }
@@ -1318,6 +1432,7 @@ void Pget_function_name(NODE arg,STRING *rp)
 }
 
 FNODE strip_paren(FNODE);
+void objtotex_tb(Obj obj,TB tb);
 
 void fnodetotex_tb(FNODE f,TB tb)
 {
@@ -1326,7 +1441,6 @@ void fnodetotex_tb(FNODE f,TB tb)
 	char *opname,*vname_conv,*prefix_conv;
 	Obj obj;
 	int i,len,allzero,elen,elen2,si;
-	C cplx;
 	char *r;
 	FNODE fi,f2,f1;
 
@@ -1394,7 +1508,14 @@ void fnodetotex_tb(FNODE f,TB tb)
 					write_tb("}",tb);
 					break;
 				case '^':
-					fnodetotex_tb((FNODE)FA1(f),tb);
+					f1 = (FNODE)FA1(f);
+					if ( fnode_is_var(f1) )
+						fnodetotex_tb(f1,tb);
+					else {
+						write_tb("(",tb);
+						fnodetotex_tb(f1,tb);
+						write_tb(")",tb);
+					}
 					write_tb("^{",tb);
 					fnodetotex_tb(strip_paren((FNODE)FA2(f)),tb);
 					write_tb("} ",tb);
@@ -1411,43 +1532,41 @@ void fnodetotex_tb(FNODE f,TB tb)
 			break;
 		case I_NARYOP:
 			args = (NODE)FA1(f);
-			write_tb("(",tb);
 			switch ( OPNAME(f) ) {
 				case '+':
 					fnodetotex_tb((FNODE)BDY(args),tb);
 					for ( args = NEXT(args); args; args = NEXT(args) ) {
 						write_tb("+",tb);
-						fnodetotex_tb((FNODE)BDY(args),tb);
+						f1 = (FNODE)BDY(args);
+						if ( fnode_is_var(f1) || IS_MUL(f1) )
+							fnodetotex_tb(f1,tb);
+						else {
+							write_tb("(",tb);
+							fnodetotex_tb(f1,tb);
+							write_tb(")",tb);
+						}
 					}
 					break;
 				case '*':
 					f1 = (FNODE)BDY(args);
-					if ( f1->id == I_FORMULA && MUNIQ(FA0(f1)) )
-						write_tb("-",tb);
-					else
-						fnodetotex_tb(f1,tb);
-					write_tb(" ",tb);
-					for ( args = NEXT(args); args; args = NEXT(args) ) {
-						/* XXX special care for DP */
+					if ( f1->id == I_FORMULA && MUNIQ(FA0(f1)) ) {
+						write_tb("- ",tb); args = NEXT(args);
+					}
+					for ( ; args; args = NEXT(args) ) {
 						f2 = (FNODE)BDY(args);
-						if ( f2->id == I_EV ) {
-							n = (NODE)FA0(f2);
-							for ( i = 0; n; n = NEXT(n), i++ ) {
-								fi = (FNODE)BDY(n);
-								if ( fi->id != I_FORMULA || FA0(fi) )
-									break;
-							}
-							if ( n )
-								fnodetotex_tb(f2,tb);
-						} else
+						if ( fnode_is_var(f2) || IS_BINARYPWR(f2) )
 							fnodetotex_tb(f2,tb);
+						else {
+							write_tb("(",tb);
+							fnodetotex_tb(f2,tb);
+							write_tb(")",tb);
+						}
 					}
 					break;
 				default:
 					error("invalid nary op");
 					break;
 			}
-			write_tb(")",tb);
 			break;
 
 		case I_COP:
@@ -1672,33 +1791,7 @@ void fnodetotex_tb(FNODE f,TB tb)
 
 		/* internal object */
 		case I_FORMULA:
-			obj = (Obj)FA0(f);
-			if ( !obj )
-				write_tb("0",tb);
-			else if ( OID(obj) == O_N && NID(obj) == N_C ) {
-				cplx = (C)obj;
-				write_tb("(",tb);
-				if ( cplx->r ) {
-					r = objtostr((Obj)cplx->r); write_tb(r,tb);
-				}
-				if ( cplx->i ) {
-					if ( cplx->r && compnum(0,cplx->i,0) > 0 ) {
-						write_tb("+",tb);
-						if ( !UNIQ(cplx->i) ) {
-							r = objtostr((Obj)cplx->i); write_tb(r,tb);
-						}
-					} else if ( MUNIQ(cplx->i) )
-						write_tb("-",tb);
-					else if ( !UNIQ(cplx->i) ) {
-						r = objtostr((Obj)cplx->i); write_tb(r,tb);
-					}
-					write_tb("\\sqrt{-1}",tb);
-				}
-				write_tb(")",tb);
-			} else if ( OID(obj) == O_P )
-				write_tb(conv_rule(VR((P)obj)->name),tb);
-			else
-				write_tb(objtostr(obj),tb);
+			objtotex_tb((Obj)FA0(f),tb);
 			break;
 
 		/* program variable */
@@ -1714,6 +1807,103 @@ void fnodetotex_tb(FNODE f,TB tb)
 	}
 }
 
+void objtotex_tb(Obj obj,TB tb)
+{
+	C cplx;
+	char *r;
+	P t;
+	DCP dc;
+	char *v;
+
+	if ( !obj ) {
+		write_tb("0",tb);
+		return;
+	}
+	switch ( OID(obj) ) {
+		case O_N:
+			switch ( NID(obj) ) {
+				case N_C:
+					cplx = (C)obj;
+					write_tb("(",tb);
+					if ( cplx->r ) {
+						r = objtostr((Obj)cplx->r); write_tb(r,tb);
+					}
+					if ( cplx->i ) {
+						if ( cplx->r && compnum(0,cplx->i,0) > 0 ) {
+							write_tb("+",tb);
+							if ( !UNIQ(cplx->i) ) {
+								r = objtostr((Obj)cplx->i); write_tb(r,tb);
+							}
+						} else if ( MUNIQ(cplx->i) )
+							write_tb("-",tb);
+						else if ( !UNIQ(cplx->i) ) {
+							r = objtostr((Obj)cplx->i); write_tb(r,tb);
+						}
+						write_tb("\\sqrt{-1}",tb);
+					}
+					write_tb(")",tb);
+					break;
+				default:
+					write_tb(objtostr(obj),tb);
+					break;
+			}
+			break;
+		case O_P:
+			v = conv_rule(VR((P)obj)->name);
+			for ( dc = DC((P)obj); dc; dc = NEXT(dc) ) {
+				if ( !DEG(dc) )
+					objtotex_tb((Obj)COEF(dc),tb);
+				else {
+					if ( NUM(COEF(dc)) && UNIQ((Q)COEF(dc)) )
+						;
+					else if ( NUM(COEF(dc)) && MUNIQ((Q)COEF(dc)) )
+						write_tb("-",tb);
+					else if ( NUM(COEF(dc)) || !NEXT(DC(COEF(dc)))) 
+						objtotex_tb((Obj)COEF(dc),tb); 
+					else {
+						write_tb("(",tb); objtotex_tb((Obj)COEF(dc),tb);
+						write_tb(")",tb);
+					}
+					write_tb(v,tb);
+					if ( cmpq(DEG(dc),ONE) ) {
+						write_tb("^",tb);
+						if ( INT(DEG(dc)) && SGN(DEG(dc))>0 ) {
+							write_tb("{",tb);
+							objtotex_tb((Obj)DEG(dc),tb);
+							write_tb("}",tb);
+						} else {
+							write_tb("{",tb); objtotex_tb((Obj)DEG(dc),tb);
+							write_tb("}",tb);
+						}
+					}
+				}
+				if ( NEXT(dc) ) {
+					t = COEF(NEXT(dc));
+					if ( !DEG(NEXT(dc)) ) {
+						if ( NUM(t) ) {
+							if ( !mmono(t) ) write_tb("+",tb);
+						} else {
+							if ( !mmono(COEF(DC(t))) ) write_tb("+",tb);
+						}
+					} else {
+						if ( !mmono(t) ) write_tb("+",tb);
+					}
+				}
+			}
+			break;
+		case O_R:
+			write_tb("\\frac{",tb);
+			objtotex_tb((Obj)NM((R)obj),tb);
+			write_tb("}{",tb);
+			objtotex_tb((Obj)DN((R)obj),tb);
+			write_tb("}",tb);
+			break;
+		default:
+			write_tb(objtostr(obj),tb);
+			break;
+	}
+}
+
 char *objtostr(Obj obj)
 {
 	int len;
@@ -1829,9 +2019,13 @@ int top_is_minus(FNODE f)
 					case O_N:
 						return mmono((P)obj);
 					case O_P:
+#if 0
 						/* must be a variable */
 						opname = conv_rule(VR((P)obj)->name);
 						return opname[0]=='-';
+#else
+						return mmono((P)obj);
+#endif
 					default:
 						/* ??? */
 						len = estimate_length(CO,obj);
@@ -2022,53 +2216,467 @@ void Pfunargs_to_quote(NODE arg,QUOTE *rp)
 	MKQUOTE(*rp,f);
 }
 
-FNODE fnode_apply(FNODE f,FNODE (*func)(),int expand);
-FNODE fnode_normalize(FNODE f,int expand);
+VL reordvars(VL vl0,NODE head)
+{
+	VL vl,svl,tvl;
+	int i,j;
+	NODE n;
+	P t;
+	V *va;
+	V v;
 
-void Pquote_normalize(NODE arg,QUOTE *rp)
+	for ( vl = 0, i = 0, n = head; n; n = NEXT(n), i++ ) {
+		NEXTVL(vl,tvl);
+		if ( !(t = (P)BDY(n)) || (OID(t) != O_P) )
+			error("reordvars : invalid argument");
+		VR(tvl) = VR(t);
+	}
+	va = (V *)ALLOCA(i*sizeof(V));
+	for ( j = 0, svl = vl; j < i; j++, svl = NEXT(svl) )
+		va[j] = VR(svl);
+	for ( svl = vl0; svl; svl = NEXT(svl) ) {
+		v = VR(svl);
+		for ( j = 0; j < i; j++ )
+			if ( v == va[j] )
+				break;
+		if ( j == i ) {
+			NEXTVL(vl,tvl);
+			VR(tvl) = v;
+		}
+	}
+	if ( vl )
+		NEXT(tvl) = 0;
+	return vl;
+}
+
+struct wtab {
+	V v;
+	int w;
+};
+
+struct wtab *qt_weight_tab;
+VL qt_current_ord, qt_current_coef;
+LIST qt_current_ord_obj,qt_current_coef_obj,qt_current_weight_obj;
+LIST qt_current_weight_obj;
+
+void Pqt_set_ord(NODE arg,LIST *rp)
 {
+	NODE r0,r;
+	VL vl;
+	P v;
+
+	if ( !argc(arg) ) 
+		*rp = qt_current_ord_obj;
+	else if ( !ARG0(arg) ) {
+		qt_current_ord_obj = 0;
+		qt_current_ord = 0;
+	} else {
+		qt_current_ord = reordvars(CO,BDY((LIST)ARG0(arg)));
+		for ( r0 = 0, vl = qt_current_ord; vl; vl = NEXT(vl) ) {
+			NEXTNODE(r0,r); MKV(vl->v,v); BDY(r) = v;
+		}
+		if ( r0 ) NEXT(r) = 0;
+		MKLIST(*rp,r0);
+		qt_current_ord_obj = *rp;
+	}
+}
+
+void Pqt_set_weight(NODE arg,LIST *rp)
+{
+	NODE n,pair;
+	int l,i;
+	struct wtab *tab;
+
+	if ( !argc(arg) ) 
+		*rp = qt_current_weight_obj;
+	else if ( !ARG0(arg) ) {
+		qt_current_weight_obj = 0;
+		qt_weight_tab = 0;
+	} else {
+		n = BDY((LIST)ARG0(arg));
+		l = length(n);
+		tab = qt_weight_tab = (struct wtab *)MALLOC((l+1)*sizeof(struct wtab));
+		for ( i = 0; i < l; i++, n = NEXT(n) ) {
+			pair = BDY((LIST)BDY(n));
+			tab[i].v = VR((P)ARG0(pair));
+			tab[i].w = QTOS((Q)ARG1(pair));
+		}
+		tab[i].v = 0;
+		qt_current_weight_obj = (LIST)ARG0(arg);
+		*rp = qt_current_weight_obj;
+	}
+}
+
+void Pqt_set_coef(NODE arg,LIST *rp)
+{
+	NODE r0,r,n;
+	VL vl0,vl;
+	P v;
+
+	if ( !argc(arg) ) 
+		*rp = qt_current_coef_obj;
+	else if ( !ARG0(arg) ) {
+		qt_current_coef_obj = 0;
+		qt_current_coef = 0;
+	} else {
+		n = BDY((LIST)ARG0(arg));
+		for ( vl0 = 0, r0 = 0; n; n = NEXT(n) ) {
+			NEXTNODE(r0,r);
+			NEXTVL(vl0,vl);
+			vl->v = VR((P)BDY(n));
+			MKV(vl->v,v); BDY(r) = v;
+		}
+		if ( r0 ) NEXT(r) = 0;
+		if ( vl0 ) NEXT(vl) = 0;
+		qt_current_coef = vl0;
+		MKLIST(*rp,r0);
+		qt_current_coef_obj = *rp;
+	}
+}
+
+void Pqt_normalize(NODE arg,QUOTE *rp)
+{
 	QUOTE q,r;
 	FNODE f;
 	int expand,ac;
 
 	ac = argc(arg);
-	if ( !ac ) error("quote_normalize : invalid argument");
+	if ( !ac ) error("qt_normalize : invalid argument");
 	q = (QUOTE)ARG0(arg);
-	expand = ac==2 && ARG1(arg);
-	if ( !q || OID(q) != O_QUOTE ) {
+	if ( ac == 2 )
+		expand = QTOS((Q)ARG1(arg));
+	if ( !q || OID(q) != O_QUOTE )
 		*rp = q;
-		return;
-	} else if ( q->normalized && (q->expanded || !expand) )
-		*rp = q;
 	else {
 		f = fnode_normalize(BDY(q),expand);
 		MKQUOTE(r,f);
-		r->normalized = 1;
-		if ( expand ) r->expanded = 1;
 		*rp = r;
 	}
 }
 
-void Pnquote_comp(NODE arg,Q *rp)
+NBP fnode_to_nbp(FNODE f);
+
+void Pqt_to_nbp(NODE arg,NBP *rp)
 {
+	QUOTE q;
+	FNODE f;
+
+	q = (QUOTE)ARG0(arg); f = (FNODE)BDY(q);
+	f = fnode_normalize(f,0);
+	*rp = fnode_to_nbp(f);
+}
+
+void Pshuffle_mul(NODE arg,NBP *rp)
+{
+	NBP p1,p2;
+
+	p1 = (NBP)ARG0(arg);
+	p2 = (NBP)ARG1(arg);
+	shuffle_mulnbp(CO,p1,p2,rp);
+}
+
+void Pharmonic_mul(NODE arg,NBP *rp)
+{
+	NBP p1,p2;
+
+	p1 = (NBP)ARG0(arg);
+	p2 = (NBP)ARG1(arg);
+	harmonic_mulnbp(CO,p1,p2,rp);
+}
+
+void Pnbp_hm(NODE arg, NBP *rp)
+{
+	NBP p;
+	NODE n;
+	NBM m;
+
+	p = (NBP)ARG0(arg);
+	if ( !p ) *rp = 0;
+	else {
+		m = (NBM)BDY(BDY(p));
+		MKNODE(n,m,0);
+		MKNBP(*rp,n);
+	}
+}
+	
+void Pnbp_ht(NODE arg, NBP *rp)
+{
+	NBP p;
+	NODE n;
+	NBM m,m1;
+
+	p = (NBP)ARG0(arg);
+	if ( !p ) *rp = 0;
+	else {
+		m = (NBM)BDY(BDY(p));
+		NEWNBM(m1);
+		m1->d = m->d; m1->c = ONE; m1->b = m->b;
+		MKNODE(n,m1,0);
+		MKNBP(*rp,n);
+	}
+}
+
+void Pnbp_hc(NODE arg, Q *rp)
+{
+	NBP p;
+	NBM m;
+
+	p = (NBP)ARG0(arg);
+	if ( !p ) *rp = 0;
+	else {
+		m = (NBM)BDY(BDY(p));
+		*rp = m->c;
+	}
+}
+
+void Pnbp_rest(NODE arg, NBP *rp)
+{
+	NBP p;
+	NODE n;
+
+	p = (NBP)ARG0(arg);
+	if ( !p ) *rp = 0;
+	else {
+		n = BDY(p);
+		if ( !NEXT(n) ) *rp = 0;
+		else
+			MKNBP(*rp,NEXT(n));
+	}
+}
+
+void Pnbm_deg(NODE arg, Q *rp)
+{
+	NBP p;
+	NBM m;
+
+	p = (NBP)ARG0(arg);
+	if ( !p )
+		STOQ(-1,*rp);
+	else {
+		m = (NBM)BDY(BDY(p));	
+		STOQ(m->d,*rp);
+	}
+}
+
+void Pnbm_hp_rest(NODE arg, LIST *rp)
+{
+	NBP p,h,r;
+	NBM m,m1;
+	NODE n;
+	int *b,*b1;
+	int d,d1,v,i,j,k;
+
+	p = (NBP)ARG0(arg);
+	if ( !p )
+		MKLIST(*rp,0);
+	else {
+		m = (NBM)BDY(BDY(p));	
+		b = m->b; d = m->d;
+		if ( !d )
+			MKLIST(*rp,0);
+		else {
+			v = NBM_GET(b,0);
+			for ( i = 1; i < d; i++ )
+				if ( NBM_GET(b,i) != v ) break;
+			NEWNBM(m1); NEWNBMBDY(m1,i); 
+			b1 = m1->b; m1->d = i; m1->c = ONE;
+			if ( v ) for ( j = 0; j < i; j++ ) NBM_SET(b1,j);
+			else for ( j = 0; j < i; j++ ) NBM_CLR(b1,j);
+			MKNODE(n,m1,0); MKNBP(h,n);
+
+			d1 = d-i;
+			NEWNBM(m1); NEWNBMBDY(m1,d1);
+			b1 = m1->b; m1->d = d1; m1->c = ONE;
+			for ( j = 0, k = i; j < d1; j++, k++ )
+				if ( NBM_GET(b,k) ) NBM_SET(b1,j);
+				else NBM_CLR(b1,j);
+			MKNODE(n,m1,0); MKNBP(r,n);
+			n = mknode(2,h,r);
+			MKLIST(*rp,n);
+		}
+	}
+}
+
+void Pnbm_hxky(NODE arg, LIST *rp)
+{
+	NBP p;
+
+	p = (NBP)ARG0(arg);
+	if ( !p )
+		*rp = 0;
+	else
+		separate_xky_nbm((NBM)BDY(BDY(p)),0,rp,0);
+}
+
+void Pnbm_xky_rest(NODE arg,NBP *rp)
+{
+	NBP p;
+
+	p = (NBP)ARG0(arg);
+	if ( !p )
+		*rp = 0;
+	else
+		separate_xky_nbm((NBM)BDY(BDY(p)),0,0,rp);
+}
+
+void Pnbm_hv(NODE arg, NBP *rp)
+{
+	NBP p;
+	
+	p = (NBP)ARG0(arg);
+	if ( !p )
+		*rp = 0;
+	else
+		separate_nbm((NBM)BDY(BDY(p)),0,rp,0);
+}
+
+void Pnbm_rest(NODE arg, NBP *rp)
+{
+	NBP p;
+	
+	p = (NBP)ARG0(arg);
+	if ( !p )
+		*rp = 0;
+	else
+		separate_nbm((NBM)BDY(BDY(p)),0,0,rp);
+}
+
+NBP fnode_to_nbp(FNODE f)
+{
+	Q r;
+	int n,i;
+	NBM m;
+	V v;
+	NBP u,u1,u2;
+	NODE t,b;
+
+	if ( f->id == I_FORMULA ) {
+		r = eval(f);
+		NEWNBM(m);
+		if ( OID(r) == O_N ) {
+			m->d = 0; m->c = (Q)r; m->b = 0;
+		} else {
+			v = VR((P)r);
+			m->d = 1; m->c = ONE; NEWNBMBDY(m,1);
+			if ( !strcmp(NAME(v),"x") ) NBM_SET(m->b,0);
+			else NBM_CLR(m->b,0);
+		}
+		MKNODE(b,m,0); MKNBP(u,b);
+		return u;
+	} else if ( IS_NARYADD(f) ) {
+		t = (NODE)FA1(f); u = fnode_to_nbp((FNODE)BDY(t));
+		for ( t = NEXT(t); t; t = NEXT(t) ) {
+			u1 = fnode_to_nbp((FNODE)BDY(t));
+			addnbp(CO,u,u1,&u2); u = u2;
+		}
+		return u;
+	} else if ( IS_NARYMUL(f) ) {
+		t = (NODE)FA1(f); u = fnode_to_nbp((FNODE)BDY(t));
+		for ( t = NEXT(t); t; t = NEXT(t) ) {
+			u1 = fnode_to_nbp((FNODE)BDY(t));
+			mulnbp(CO,u,u1,&u2); u = u2;
+		}
+		return u;
+	} else if ( IS_BINARYPWR(f) ) {
+		u = fnode_to_nbp((FNODE)FA1(f));
+		r = eval((FNODE)FA2(f));
+		pwrnbp(CO,u,r,&u1);
+		return u1;
+	}
+}
+
+void Pnqt_weight(NODE arg,Q *rp)
+{
+	QUOTE q;
+	FNODE f;
+	int w;
+
+	q = (QUOTE)ARG0(arg); f = (FNODE)BDY(q);
+	f = fnode_normalize(f,0);
+	w = nfnode_weight(qt_weight_tab,f);
+	STOQ(w,*rp);
+}
+
+void Pnqt_comp(NODE arg,Q *rp)
+{
 	QUOTE q1,q2;
 	FNODE f1,f2;
 	int r;
 
 	q1 = (QUOTE)ARG0(arg); f1 = (FNODE)BDY(q1);
 	q2 = (QUOTE)ARG1(arg); f2 = (FNODE)BDY(q2);
-	if ( !q1->normalized ) f1 = fnode_normalize(f1,0);
-	if ( !q2->normalized ) f2 = fnode_normalize(f2,0);
+	f1 = fnode_normalize(f1,0);
+	f2 = fnode_normalize(f2,0);
 	r = nfnode_comp(f1,f2);
 	STOQ(r,*rp);
 }
 
-INLINE int fnode_is_number(FNODE f)
+int fnode_is_var(FNODE f)
 {
 	Obj obj;
+	VL vl,t,s;
+	DCP dc;
 
+	if ( fnode_is_coef(f) ) return 0;
 	switch ( f->id ) {
+		case I_PAREN:
+			return fnode_is_var(FA0(f));
+				
+		case I_FORMULA:
+			obj = FA0(f);
+			if ( obj && OID(obj) == O_P ) {
+				dc = DC((P)obj);
+				if ( !cmpq(DEG(dc),ONE) && !NEXT(dc) 
+					&& !arf_comp(CO,(Obj)COEF(dc),(Obj)ONE) ) return 1;
+				else return 0;
+			} else return 0;
+		
+		default:
+			return 0;
+	}
+}
+
+int fnode_is_coef(FNODE f)
+{
+	Obj obj;
+	VL vl,t,s;
+
+	switch ( f->id ) {
 		case I_MINUS: case I_PAREN:
+			return fnode_is_coef(FA0(f));
+				
+		case I_FORMULA:
+			obj = FA0(f);
+			if ( !obj ) return 1;
+			else if ( OID(obj) == O_QUOTE ) 
+				return fnode_is_coef(BDY((QUOTE)obj));
+			else if ( NUM(obj) ) return 1;
+			else if ( OID(obj) == O_P || OID(obj) == O_R) {
+				get_vars_recursive(obj,&vl);
+				for ( t = vl; t; t = NEXT(t) ) {
+					if ( t->v->attr == (pointer)V_PF ) continue;
+					for ( s = qt_current_coef; s; s = NEXT(s) )
+						if ( t->v == s->v ) break;
+					if ( !s )
+						return 0;
+				}
+				return 1;
+			} else return 0;
+		
+		case I_BOP:
+			return fnode_is_coef(FA1(f)) && fnode_is_coef(FA2(f));
+		
+		default:
+			return 0;
+	}
+}
+
+int fnode_is_number(FNODE f)
+{
+	Obj obj;
+
+	switch ( f->id ) {
+		case I_MINUS: case I_PAREN:
 			return fnode_is_number(FA0(f));
 				
 		case I_FORMULA:
@@ -2207,26 +2815,14 @@ int fnode_is_dependent(FNODE f,V v)
 	}
 }
 
-FNODE nfnode_add(FNODE a1,FNODE a2,int expand);
-FNODE nfnode_mul(FNODE a1,FNODE a2,int expand);
-FNODE nfnode_pwr(FNODE a1,FNODE a2,int expand);
-FNODE nfnode_mul_coef(Num c,FNODE f,int expand);
-FNODE fnode_expand_pwr(FNODE f,int n);
-FNODE to_narymul(FNODE f);
-FNODE to_naryadd(FNODE f);
-FNODE fnode_node_to_naryadd(NODE n);
-FNODE fnode_node_to_narymul(NODE n);
-void fnode_base_exp(FNODE f,FNODE *bp,FNODE *ep);
-void fnode_coef_body(FNODE f,Num *cp,FNODE *bp);
 
-
 FNODE fnode_normalize(FNODE f,int expand)
 {
 	FNODE a1,a2,mone,r,b2;
 	NODE n;
 	Q q;
 
-	if ( f->normalized && (f->expanded || !expand) ) return f;
+	if ( f->normalized && (f->expanded == expand) ) return f;
 	STOQ(-1,q);
 	mone = mkfnode(1,I_FORMULA,q);
 	switch ( f->id ) {
@@ -2235,7 +2831,7 @@ FNODE fnode_normalize(FNODE f,int expand)
 			break;
 		
 		case I_MINUS:
-			r = nfnode_mul_coef((Num)q,
+			r = nfnode_mul_coef((Obj)q,
 				fnode_normalize(FA0(f),expand),expand);
 			break;
 
@@ -2248,7 +2844,7 @@ FNODE fnode_normalize(FNODE f,int expand)
 					r = nfnode_add(a1,a2,expand);
 					break;
 				case '-':
-					a2 = nfnode_mul_coef((Num)q,a2,expand);
+					a2 = nfnode_mul_coef((Obj)q,a2,expand);
 					r = nfnode_add(a1,a2,expand);
 					break;
 				case '*':
@@ -2335,7 +2931,7 @@ FNODE nfnode_add(FNODE f1,FNODE f2,int expand)
 	NODE n1,n2,r0,r;
 	FNODE b1,b2;
 	int s;
-	Num c1,c2,c;
+	Obj c1,c2,c;
 
 	if ( IS_ZERO(f1) ) return f2;
 	else if ( IS_ZERO(f2) ) return f1;
@@ -2349,7 +2945,7 @@ FNODE nfnode_add(FNODE f1,FNODE f2,int expand)
 		} else if ( s < 0 ) {
 			NEXTNODE(r0,r); BDY(r) = BDY(n2); n2 = NEXT(n2);
 		} else {
-			addnum(0,c1,c2,&c);
+			arf_add(CO,c1,c2,&c);
 			if ( c ) {
 				NEXTNODE(r0,r); BDY(r) = nfnode_mul_coef(c,b1,expand);
 			}
@@ -2365,37 +2961,34 @@ FNODE nfnode_add(FNODE f1,FNODE f2,int expand)
 	else if ( r0 )
 		NEXT(r) = 0;
 
-	return fnode_node_to_naryadd(r0);
+	return fnode_node_to_nary(addfs,r0);
 }
 
-FNODE fnode_node_to_naryadd(NODE n)
+FNODE fnode_node_to_nary(ARF op,NODE n)
 {
-	if ( !n ) return mkfnode(1,I_FORMULA,0);
-	else if ( !NEXT(n) ) return BDY(n);
-	else return mkfnode(2,I_NARYOP,addfs,n);
+	if ( !n ) {
+		if ( op->name[0] == '+' )
+			return mkfnode(1,I_FORMULA,0);
+		else
+			return mkfnode(1,I_FORMULA,ONE);
+	} else if ( !NEXT(n) ) return BDY(n);
+	else return mkfnode(2,I_NARYOP,op,n);
 }
 
-FNODE fnode_node_to_narymul(NODE n)
-{
-	if ( !n ) return mkfnode(1,I_FORMULA,ONE);
-	else if ( !NEXT(n) ) return BDY(n);
-	else return mkfnode(2,I_NARYOP,mulfs,n);
-}
-
 FNODE nfnode_mul(FNODE f1,FNODE f2,int expand)
 {
 	NODE n1,n2,r0,r,r1;
 	FNODE b1,b2,e1,e2,cc,t,t1;
 	FNODE *m;
 	int s;
-	Num c1,c2,c,e;
+	Obj c1,c2,c,e;
 	int l1,l,i,j;
 
 	if ( IS_ZERO(f1) || IS_ZERO(f2) ) return mkfnode(1,I_FORMULA,0);
-	else if ( fnode_is_number(f1) ) 
-		return nfnode_mul_coef((Num)eval(f1),f2,expand);
-	else if ( fnode_is_number(f2) ) 
-		return nfnode_mul_coef((Num)eval(f2),f1,expand);
+	else if ( fnode_is_coef(f1) ) 
+		return nfnode_mul_coef((Obj)eval(f1),f2,expand);
+	else if ( fnode_is_coef(f2) ) 
+		return nfnode_mul_coef((Obj)eval(f2),f1,expand);
 
 	if ( expand && IS_NARYADD(f1) ) {
 		t = mkfnode(1,I_FORMULA,0);
@@ -2415,7 +3008,7 @@ FNODE nfnode_mul(FNODE f1,FNODE f2,int expand)
 	}
 
 	fnode_coef_body(f1,&c1,&b1); fnode_coef_body(f2,&c2,&b2);
-	mulnum(0,c1,c2,&c);
+	arf_mul(CO,c1,c2,&c);
 	if ( !c ) return mkfnode(1,I_FORMULA,0);
 
 
@@ -2429,9 +3022,19 @@ FNODE nfnode_mul(FNODE f1,FNODE f2,int expand)
 		else {
 			fnode_base_exp(m[i-1],&b1,&e1); fnode_base_exp(BDY(r),&b2,&e2);
 			if ( compfnode(b1,b2) ) break;
-			addnum(0,eval(e1),eval(e2),&e);
+			arf_add(CO,eval(e1),eval(e2),&e);
 			if ( !e ) i--;
-			else if ( UNIQ(e) )
+			else if ( expand == 2 ) {
+				if ( INT(e) && SGN((Q)e) < 0 ) {
+					t1 = mkfnode(3,I_BOP,pwrfs,b1,mkfnode(1,I_FORMULA,e));
+					/* r=(r0|rest)->(r0,t1|rest) */
+					t = BDY(r);
+					MKNODE(r1,t1,NEXT(r));
+					MKNODE(r,t,r1);
+					i--;
+				} else
+					m[i++] = BDY(r);
+			} else if ( UNIQ(e) )
 				m[i-1] = b1;
 			else
 				m[i-1] = mkfnode(3,I_BOP,pwrfs,b1,mkfnode(1,I_FORMULA,e));
@@ -2443,28 +3046,31 @@ FNODE nfnode_mul(FNODE f1,FNODE f2,int expand)
 	if ( !UNIQ(c) ) {
 		cc = mkfnode(1,I_FORMULA,c); MKNODE(r1,cc,r); r = r1;
 	}
-	return fnode_node_to_narymul(r);
+	return fnode_node_to_nary(mulfs,r);
 }
 
 FNODE nfnode_pwr(FNODE f1,FNODE f2,int expand)
 {
 	FNODE b,b1,e1,e,cc,r,mf2,mone,inv;
-	Num c,c1,nf2;
+	Obj c,c1;
+	Num nf2;
 	int ee;
 	NODE arg,n,t0,t1;
 	Q q;
 
 	if ( IS_ZERO(f2) ) return mkfnode(1,I_FORMULA,ONE);
 	else if ( IS_ZERO(f1) ) return mkfnode(1,I_FORMULA,0);
-	else if ( fnode_is_number(f1) ) {
+	else if ( fnode_is_coef(f1) ) {
 		if ( fnode_is_integer(f2) ) {
 			if ( fnode_is_one(f2) ) return f1;
 			else {
-				pwrnum(0,(Num)eval(f1),(Num)eval(f2),&c);
+				arf_pwr(CO,eval(f1),(Obj)eval(f2),&c);
 				return mkfnode(1,I_FORMULA,c);
 			}
-		} else
+		} else {
+			f1 = mkfnode(1,I_FORMULA,eval(f1));
 			return mkfnode(3,I_BOP,pwrfs,f1,f2);
+		}
 	} else if ( IS_BINARYPWR(f1) ) {
 		b1 = FA1(f1); e1 = FA2(f1);
 		e = nfnode_mul(e1,f2,expand);
@@ -2476,11 +3082,11 @@ FNODE nfnode_pwr(FNODE f1,FNODE f2,int expand)
 		&& fnode_is_integer(f2) ) {
 		fnode_coef_body(f1,&c1,&b1);
 		nf2 = (Num)eval(f2);
-		pwrnum(0,(Num)c1,nf2,&c);
+		arf_pwr(CO,c1,(Obj)nf2,&c);
 		ee = QTOS((Q)nf2);
 		cc = mkfnode(1,I_FORMULA,c);
 		if ( fnode_is_nonnegative_integer(f2) )
-			b = fnode_expand_pwr(b1,ee);
+			b = fnode_expand_pwr(b1,ee,expand);
 		else {
 			STOQ(-1,q);
 			mone = mkfnode(1,I_FORMULA,q);
@@ -2489,36 +3095,48 @@ FNODE nfnode_pwr(FNODE f1,FNODE f2,int expand)
 				inv = mkfnode(3,I_BOP,pwrfs,BDY(n),mone);
 				MKNODE(t1,inv,t0); t0 = t1;
 			}
-			b1 = fnode_node_to_narymul(t0);
-			b = fnode_expand_pwr(b1,-ee);
+			b1 = fnode_node_to_nary(mulfs,t0);
+			b = fnode_expand_pwr(b1,-ee,expand);
 		}
 		if ( fnode_is_one(cc) )
 			return b;
 		else
-			return fnode_node_to_narymul(mknode(2,cc,b));
+			return fnode_node_to_nary(mulfs,mknode(2,cc,b));
 	} else if ( expand && fnode_is_integer(f2) 
 			&& fnode_is_nonnegative_integer(f2) ) {
 		q = (Q)eval(f2);
 		if ( PL(NM(q)) > 1 ) error("nfnode_pwr : exponent too large");
-		return fnode_expand_pwr(f1,QTOS(q));
+		return fnode_expand_pwr(f1,QTOS(q),expand);
 	} else
 		return mkfnode(3,I_BOP,pwrfs,f1,f2);
 }
 
-FNODE fnode_expand_pwr(FNODE f,int n)
+FNODE fnode_expand_pwr(FNODE f,int n,int expand)
 {
-	int n1;
-	FNODE f1,f2;
+	int n1,i;
+	FNODE f1,f2,fn;
+	Q q;
 
 	if ( !n ) return mkfnode(1,I_FORMULA,ONE);
 	else if ( IS_ZERO(f) ) return mkfnode(1,I_FORMULA,0);
 	else if ( n == 1 ) return f;
 	else {
-		n1 = n/2;
-		f1 = fnode_expand_pwr(f,n1);
-		f2 = nfnode_mul(f1,f1,1);
-		if ( n%2 ) f2 = nfnode_mul(f2,f,1);
-		return f2;
+		switch ( expand ) {
+			case 1:
+				n1 = n/2;
+				f1 = fnode_expand_pwr(f,n1,expand);
+				f2 = nfnode_mul(f1,f1,expand);
+				if ( n%2 ) f2 = nfnode_mul(f2,f,1);
+				return f2;
+			case 2:
+				for ( i = 1, f1 = f; i < n; i++ )
+					f1 = nfnode_mul(f1,f,expand);
+				return f1;
+			case 0: default:
+				STOQ(n,q);
+				fn = mkfnode(1,I_FORMULA,q);
+				return mkfnode(3,I_BOP,pwrfs,f,fn);
+		}
 	}
 }
 
@@ -2556,17 +3174,17 @@ FNODE to_narymul(FNODE f)
 	return r;
 }
 
-FNODE nfnode_mul_coef(Num c,FNODE f,int expand)
+FNODE nfnode_mul_coef(Obj c,FNODE f,int expand)
 {
 	FNODE b1,cc;
-	Num c1,c2;
+	Obj c1,c2;
 	NODE n,r,r0;
 
 	if ( !c )
 		return mkfnode(I_FORMULA,0);
 	else {
 		fnode_coef_body(f,&c1,&b1);
-		mulnum(0,c,c1,&c2);
+		arf_mul(CO,c,c1,&c2);
 		if ( UNIQ(c2) ) return b1;
 		else {
 			cc = mkfnode(1,I_FORMULA,c2);
@@ -2577,54 +3195,122 @@ FNODE nfnode_mul_coef(Num c,FNODE f,int expand)
 					return cc;
 			} else if ( IS_NARYMUL(b1) ) {
 				MKNODE(n,cc,FA1(b1));
-				return fnode_node_to_narymul(n);
+				return fnode_node_to_nary(mulfs,n);
 			} else if ( expand && IS_NARYADD(b1) ) {
 				for ( r0 = 0, n = (NODE)FA1(b1); n; n = NEXT(n) ) {
 					NEXTNODE(r0,r);
 					BDY(r) = nfnode_mul_coef(c2,BDY(n),expand);
 				}
 				if ( r0 ) NEXT(r) = 0;
-				return fnode_node_to_naryadd(r0);
+				return fnode_node_to_nary(addfs,r0);
 			} else 
-				return fnode_node_to_narymul(mknode(2,cc,b1));
+				return fnode_node_to_nary(mulfs,mknode(2,cc,b1));
 		}
 	}
 }
 
-void fnode_coef_body(FNODE f,Num *cp,FNODE *bp)
+void fnode_coef_body(FNODE f,Obj *cp,FNODE *bp)
 {
 	FNODE c;
 
-	if ( fnode_is_number(f) ) {
-		*cp = eval(f); *bp = mkfnode(1,I_FORMULA,ONE);
+	if ( fnode_is_coef(f) ) {
+		*cp = (Obj)eval(f); *bp = mkfnode(1,I_FORMULA,ONE);
 	} else if ( IS_NARYMUL(f) ) {
 		c=(FNODE)BDY((NODE)FA1(f));
-		if ( fnode_is_number(c) ) {
-			*cp = eval(c);
-			*bp = fnode_node_to_narymul(NEXT((NODE)FA1(f)));
+		if ( fnode_is_coef(c) ) {
+			*cp = (Obj)eval(c);
+			*bp = fnode_node_to_nary(mulfs,NEXT((NODE)FA1(f)));
 		} else {
-			*cp = (Num)ONE; *bp = f;
+			*cp = (Obj)ONE; *bp = f;
 		}
 	} else {
-		*cp = (Num)ONE; *bp = f;
+		*cp = (Obj)ONE; *bp = f;
 	}
 }
 
-int nfnode_comp_pwr(FNODE f1,FNODE f2);
+int nfnode_weight(struct wtab *tab,FNODE f)
+{
+	NODE n;
+	int w,w1;
+	int i;
+	Q a2;
+	V v;
 
+	switch ( f->id ) {
+		case I_FORMULA:
+			if ( fnode_is_coef(f) ) return 0;
+			else if ( fnode_is_var(f) ) {
+				if ( !tab ) return 0;
+				v = VR((P)FA0(f));
+				for ( i = 0; tab[i].v; i++ )
+					if ( v == tab[i].v ) return tab[i].w;
+				return 0;
+			} else return 0;
+
+		/* XXX */
+		case I_PVAR: return 1;
+		/* XXX */
+		case I_FUNC: I_FUNC: I_FUNC_QARG:
+			/* w(f) = 1 */
+			/* w(f(a1,...,an)=w(a1)+...+w(an) */
+			n = FA0((FNODE)FA1(f));
+			for ( w = 0; n; n = NEXT(n) )
+				w += nfnode_weight(tab,BDY(n));
+			return w;
+		case I_NARYOP:
+			n = (NODE)FA1(f);
+			if ( IS_NARYADD(f) )
+				for ( w = nfnode_weight(tab,BDY(n)),
+					n = NEXT(n); n; n = NEXT(n) ) {
+					w1 = nfnode_weight(tab,BDY(n));
+					w = MAX(w,w1);
+				}
+			else
+				for ( w = 0; n; n = NEXT(n) )
+					w += nfnode_weight(tab,BDY(n));
+			return w;
+		case I_BOP:
+			/* must be binary power */
+			/* XXX w(2^x)=0 ? */
+			if ( fnode_is_rational(FA2(f)) ) {
+				a2 = (Q)eval(FA2(f));
+				w = QTOS(a2);
+			} else
+				w = nfnode_weight(tab,FA2(f));
+			return nfnode_weight(tab,FA1(f))*w;
+		default:
+			error("nfnode_weight : not_implemented");
+	}
+}
+
 int nfnode_comp(FNODE f1,FNODE f2)
 {
+	int w1,w2;
+
+	if ( qt_weight_tab ) {
+		w1 = nfnode_weight(qt_weight_tab,f1);
+		w2 = nfnode_weight(qt_weight_tab,f2);
+		if ( w1 > w2 ) return 1;
+		if ( w1 < w2 ) return -1;
+	}
+	return nfnode_comp_lex(f1,f2);
+}
+
+int nfnode_comp_lex(FNODE f1,FNODE f2)
+{
 	NODE n1,n2;
 	int r,i1,i2,ret;
 	char *nm1,*nm2;
 	FNODE b1,b2,e1,e2,g,a1,a2,fn1,fn2;
-	Num ee,ee1,c1,c2;
+	Num ee,ee1;
+	Obj c1,c2;
+	int w1,w2;
 
 	if ( IS_NARYADD(f1) || IS_NARYADD(f2) ) {
 		f1 = to_naryadd(f1); f2 = to_naryadd(f2);
 		n1 = (NODE)FA1(f1); n2 = (NODE)FA1(f2);
 		while ( n1 && n2 )
-			if ( r = nfnode_comp(BDY(n1),BDY(n2)) ) return r;
+			if ( r = nfnode_comp_lex(BDY(n1),BDY(n2)) ) return r;
 			else {
 				n1 = NEXT(n1); n2 = NEXT(n2);
 			}
@@ -2633,7 +3319,7 @@ int nfnode_comp(FNODE f1,FNODE f2)
 	if ( IS_NARYMUL(f1) || IS_NARYMUL(f2) ) {
 		fnode_coef_body(f1,&c1,&b1);
 		fnode_coef_body(f2,&c2,&b2);
-		if ( !compfnode(b1,b2) ) return compnum(0,c1,c2);
+		if ( !compfnode(b1,b2) ) return arf_comp(CO,c1,c2);
 		b1 = to_narymul(b1); b2 = to_narymul(b2);
 		n1 = (NODE)FA1(b1); n2 = (NODE)FA1(b2);
 		while ( 1 ) {
@@ -2646,11 +3332,11 @@ int nfnode_comp(FNODE f1,FNODE f2)
 			fnode_base_exp(BDY(n1),&b1,&e1);
 			fnode_base_exp(BDY(n2),&b2,&e2);
 
-			if ( r = nfnode_comp(b1,b2) ) {
+			if ( r = nfnode_comp_lex(b1,b2) ) {
 				if ( r > 0 )
-					return nfnode_comp(e1,mkfnode(1,I_FORMULA,0));
+					return nfnode_comp_lex(e1,mkfnode(1,I_FORMULA,0));
 				else if ( r < 0 )
-					return nfnode_comp(mkfnode(1,I_FORMULA,0),e2);
+					return nfnode_comp_lex(mkfnode(1,I_FORMULA,0),e2);
 			} else {
 				n1 = NEXT(n1); n2 = NEXT(n2);
 				if ( fnode_is_number(e1) && fnode_is_number(e2) ) {
@@ -2666,36 +3352,44 @@ int nfnode_comp(FNODE f1,FNODE f2)
 						MKNODE(n2,g,n2);
 					}
 				} else {
-					r = nfnode_comp(e1,e2);
+					r = nfnode_comp_lex(e1,e2);
 					if ( r > 0 ) return 1;
 					else if ( r < 0 ) return -1;
 				}
 			}
 		}
 	}
-	if ( IS_BINARYPWR(f1) || IS_BINARYPWR(f2) )
-		return nfnode_comp_pwr(f1,f2);
+	if ( IS_BINARYPWR(f1) || IS_BINARYPWR(f2) ) {
+		fnode_base_exp(f1,&b1,&e1);
+		fnode_base_exp(f2,&b2,&e2);
+		if ( r = nfnode_comp_lex(b1,b2) ) {
+			if ( r > 0 )
+				return nfnode_comp_lex(e1,mkfnode(1,I_FORMULA,0));
+			else if ( r < 0 )
+				return nfnode_comp_lex(mkfnode(1,I_FORMULA,0),e2);
+		} else return nfnode_comp_lex(e1,e2);
+	}
 				
 	/* now, IDs of f1 and f2 must be I_FORMULA, I_FUNC, I_IFUNC or I_PVAR */
-	/* I_IFUNC > I_PVAR > I_FUNC > I_FORMULA */
+	/* I_IFUNC > I_PVAR > I_FUNC=I_FUNC_QARG > I_FORMULA */
 	switch ( f1->id ) {
 		case I_FORMULA:
 			switch ( f2->id ) {
 				case I_FORMULA:
-					return arf_comp(CO,FA0(f1),FA0(f2));
+					return arf_comp(qt_current_ord?qt_current_ord:CO,FA0(f1),FA0(f2));
 				case I_FUNC: case I_IFUNC: case I_PVAR:
 					return -1;
 				default:
-					error("nfnode_comp : undefined");
+					error("nfnode_comp_lex : undefined");
 			}
 			break;
-		case I_FUNC:
+		case I_FUNC: case I_FUNC_QARG:
 			switch ( f2->id ) {
 				case I_FORMULA:
 					return 1;
 				case I_PVAR: case I_IFUNC:
 					return -1;
-				case I_FUNC:
+				case I_FUNC: case I_FUNC_QARG:
 					nm1 = ((FUNC)FA0(f1))->name; nm2 = ((FUNC)FA0(f2))->name;
 					r = strcmp(nm1,nm2);
 					if ( r > 0 ) return 1;
@@ -2704,7 +3398,7 @@ int nfnode_comp(FNODE f1,FNODE f2)
 						/* compare args */
 						n1 = FA0((FNODE)FA1(f1)); n2 = FA0((FNODE)FA1(f2));
 						while ( n1 && n2 )
-							if ( r = nfnode_comp(BDY(n1),BDY(n2)) ) return r;
+							if ( r = nfnode_comp_lex(BDY(n1),BDY(n2)) ) return r;
 							else {
 								n1 = NEXT(n1); n2 = NEXT(n2);
 							}
@@ -2712,11 +3406,11 @@ int nfnode_comp(FNODE f1,FNODE f2)
 					}
 					break;
 				default:
-					error("nfnode_comp : undefined");
+					error("nfnode_comp_lex : undefined");
 			}
 		case I_PVAR:
 			switch ( f2->id ) {
-				case I_FORMULA: case I_FUNC:
+				case I_FORMULA: case I_FUNC: case I_FUNC_QARG:
 					return 1;
 				case I_IFUNC:
 					return -1;
@@ -2726,12 +3420,12 @@ int nfnode_comp(FNODE f1,FNODE f2)
 					else if ( i1 < i2 ) return -1;
 					else return 0;
 				default:
-					error("nfnode_comp : undefined");
+					error("nfnode_comp_lex : undefined");
 			}
 			break;
 		case I_IFUNC:
 			switch ( f2->id ) {
-				case I_FORMULA: case I_FUNC: case I_PVAR:
+				case I_FORMULA: case I_FUNC: case I_FUNC_QARG: case I_PVAR:
 					return 1;
 				case I_IFUNC:
 					i1 = (int)FA0((FNODE)FA0(f1));
@@ -2742,7 +3436,7 @@ int nfnode_comp(FNODE f1,FNODE f2)
 						/* compare args */
 						n1 = FA0((FNODE)FA1(f1)); n2 = FA0((FNODE)FA1(f2));
 						while ( n1 && n2 )
-							if ( r = nfnode_comp(BDY(n1),BDY(n2)) ) return r;
+							if ( r = nfnode_comp_lex(BDY(n1),BDY(n2)) ) return r;
 							else {
 								n1 = NEXT(n1); n2 = NEXT(n2);
 							}
@@ -2751,29 +3445,14 @@ int nfnode_comp(FNODE f1,FNODE f2)
 					break;
 
 				default:
-					error("nfnode_comp : undefined");
+					error("nfnode_comp_lex : undefined");
 			}
 			break;
 		default:
-			error("nfnode_comp : undefined");
+			error("nfnode_comp_lex : undefined");
 	}
 }
 
-int nfnode_comp_pwr(FNODE f1,FNODE f2)
-{
-	FNODE b1,b2,e1,e2;
-	int r;
-
-	fnode_base_exp(f1,&b1,&e1);
-	fnode_base_exp(f2,&b2,&e2);
-	if ( r = nfnode_comp(b1,b2) ) {
-		if ( r > 0 )
-			return nfnode_comp(e1,mkfnode(1,I_FORMULA,0));
-		else if ( r < 0 )
-			return nfnode_comp(mkfnode(1,I_FORMULA,0),e2);
-	} else return nfnode_comp(e1,e2);
-}
-
 NODE append_node(NODE a1,NODE a2)
 {
 	NODE t,t0;
@@ -2798,10 +3477,18 @@ int nfnode_match(FNODE f,FNODE pat,NODE *rp)
 	FUNC ff,pf;
 	int r;
 
+	if ( !pat )
+		if ( !f ) {
+			*rp = 0;
+			return 1;
+		} else
+			return 0;
+	else if ( !f )
+		return 0;
 	switch ( pat->id ) {
 		case I_PVAR:
 			/* [[pat,f]] */
-			*rp = mknode(1,mknode(2,(int)FA0(pat),f),0);
+			*rp = mknode(1,mknode(2,(int)FA0(pat),f));
 			return 1;
 
 		case I_FORMULA:
@@ -2820,7 +3507,7 @@ int nfnode_match(FNODE f,FNODE pat,NODE *rp)
 				fbase = f; fexp = mkfnode(1,I_FORMULA,ONE);
 			}
 			if ( !nfnode_match(fbase,FA1(pat),&base) ) return 0;
-			a = rewrite_fnode(FA2(pat),base);
+			a = rewrite_fnode(FA2(pat),base,0);
 			if ( !nfnode_match(fexp,a,&exp) ) return 0;
 			else {
 				*rp = append_node(base,exp);
@@ -2844,7 +3531,7 @@ int nfnode_match(FNODE f,FNODE pat,NODE *rp)
 			fa = (NODE)FA0((FNODE)FA1(f));
 			pa = (NODE)FA0((FNODE)FA1(pat));
 			while ( fa && pa ) {
-				a = rewrite_fnode(BDY(pa),m);
+				a = rewrite_fnode(BDY(pa),m,0);
 				if ( !nfnode_match(BDY(fa),a,&m1) ) return 0;
 				m = append_node(m1,m);
 				fa = NEXT(fa); pa = NEXT(pa);
@@ -2880,14 +3567,14 @@ FNODE fnode_removeith_naryadd(FNODE p,int i)
 	l = length(a);
 	if ( i < 0 || i >= l ) error("fnode_removeith_naryadd: invalid index");
 	else if ( i == 0 )
-		return fnode_node_to_naryadd(NEXT(a));
+		return fnode_node_to_nary(addfs,NEXT(a));
 	else {
 		for ( r0 = 0, k = 0, t = a; k < i; k++, t = NEXT(t) ) {
 			NEXTNODE(r0,r);
 			BDY(r) = BDY(t);
 		}
 		NEXT(r) = NEXT(t);
-		return fnode_node_to_naryadd(r0);
+		return fnode_node_to_nary(addfs,r0);
 	}
 	
 }
@@ -2901,7 +3588,7 @@ FNODE fnode_left_narymul(FNODE p,int i)
 	a = (NODE)FA1(p);
 	l = length(a);
 	if ( i < 0 || i >= l ) error("fnode_left_narymul : invalid index");
-	if ( i == 0 ) return mkfnode(1,I_FORMULA,ONE);
+	if ( i == 0 ) return 0;
 	else if ( i == 1 ) return (FNODE)BDY(a);
 	else {
 		for ( r0 = 0, k = 0, t = a; k < i; k++, t = NEXT(t) ) {
@@ -2909,7 +3596,7 @@ FNODE fnode_left_narymul(FNODE p,int i)
 			BDY(r) = BDY(t);
 		}
 		NEXT(r) = 0;
-		return fnode_node_to_narymul(r0);
+		return fnode_node_to_nary(mulfs,r0);
 	}
 }
 
@@ -2922,10 +3609,10 @@ FNODE fnode_right_narymul(FNODE p,int i)
 	a = (NODE)FA1(p);
 	l = length(a);
 	if ( i < 0 || i >= l ) error("fnode_right_narymul : invalid index");
-	if ( i == l-1 ) return mkfnode(1,I_FORMULA,ONE);
+	if ( i == l-1 ) return 0;
 	else {
 		for ( k = 0, t = a; k <= i; k++, t = NEXT(t) );
-		return fnode_node_to_narymul(t);
+		return fnode_node_to_nary(mulfs,t);
 	}
 }
 
@@ -2967,7 +3654,7 @@ int nfnode_match_naryadd(FNODE f,FNODE p,NODE *rp)
 			for ( s = fa, fi = 0; s; s = NEXT(s), fi++ ) {
 				if ( nfnode_match(BDY(s),pivot,&m) ) {
 					fr = fnode_removeith_naryadd(f,fi);
-					prr = rewrite_fnode(pr,m);
+					prr = rewrite_fnode(pr,m,0);
 					if ( nfnode_match(fr,prr,&m1) ) {
 						*rp = append_node(m,m1);
 						return 1;
@@ -3001,7 +3688,7 @@ int nfnode_match_narymul(FNODE f,FNODE p,NODE *rp)
 			/* all are I_PVAR */
 			m = 0;
 			for ( t = pa, s = fa; NEXT(t); t = NEXT(t), s = NEXT(s) ) {
-				pr = rewrite_fnode(BDY(t),m);
+				pr = rewrite_fnode(BDY(t),m,0);
 				if ( !nfnode_match(BDY(s),pr,&m1) ) return 0;
 				m = append_node(m1,m);
 			}
@@ -3009,7 +3696,7 @@ int nfnode_match_narymul(FNODE f,FNODE p,NODE *rp)
 				fr = (FNODE)BDY(s);
 			else
 				fr = mkfnode(2,I_NARYOP,FA0(f),s);
-			pr = rewrite_fnode(BDY(t),m);
+			pr = rewrite_fnode(BDY(t),m,0);
 			if ( !nfnode_match(fr,pr,&m1) ) return 0;
 			*rp = append_node(m1,m);
 			return 1;
@@ -3019,13 +3706,14 @@ int nfnode_match_narymul(FNODE f,FNODE p,NODE *rp)
 			pright = fnode_right_narymul(p,pi);
 			/* XXX : incomplete */
 			for ( s = fa, fi = 0; s; s = NEXT(s), fi++ ) {
+				if ( fi < pi ) continue;
 				if ( nfnode_match(BDY(s),pivot,&m) ) {
 					fleft = fnode_left_narymul(f,fi);
-					pleft1 = rewrite_fnode(pleft,m);
+					pleft1 = rewrite_fnode(pleft,m,0);
 					if ( nfnode_match(fleft,pleft1,&m1) ) {
 						m = append_node(m1,m);
 						fright = fnode_right_narymul(f,fi);
-						pright1 = rewrite_fnode(pright,m);
+						pright1 = rewrite_fnode(pright,m,0);
 						if ( nfnode_match(fright,pright1,&m1) ) {
 							*rp = append_node(m1,m);
 							return 1;