]> www.ginac.de Git - ginac.git/blobdiff - ginac/normal.cpp
Fixed initialization order bug (references to flyweights removed!) [C.Dams].
[ginac.git] / ginac / normal.cpp
index 9e9bde18f0f65a4a9583091986a47250f18312a8..64c34ac290037348d835420d49ff1b2bf019000a 100644 (file)
@@ -233,14 +233,14 @@ static numeric lcmcoeff(const ex &e, const numeric &l)
        if (e.info(info_flags::rational))
                return lcm(ex_to<numeric>(e).denom(), l);
        else if (is_exactly_a<add>(e)) {
-               numeric c = _num1;
+               numeric c = *_num1_p;
                for (size_t i=0; i<e.nops(); i++)
                        c = lcmcoeff(e.op(i), c);
                return lcm(c, l);
        } else if (is_exactly_a<mul>(e)) {
-               numeric c = _num1;
+               numeric c = *_num1_p;
                for (size_t i=0; i<e.nops(); i++)
-                       c *= lcmcoeff(e.op(i), _num1);
+                       c *= lcmcoeff(e.op(i), *_num1_p);
                return lcm(c, l);
        } else if (is_exactly_a<power>(e)) {
                if (is_a<symbol>(e.op(0)))
@@ -260,7 +260,7 @@ static numeric lcmcoeff(const ex &e, const numeric &l)
  *  @return LCM of denominators of coefficients */
 static numeric lcm_of_coefficients_denominators(const ex &e)
 {
-       return lcmcoeff(e, _num1);
+       return lcmcoeff(e, *_num1_p);
 }
 
 /** Bring polynomial from Q[X] to Z[X] by multiplying in the previously
@@ -273,9 +273,9 @@ static ex multiply_lcm(const ex &e, const numeric &lcm)
        if (is_exactly_a<mul>(e)) {
                size_t num = e.nops();
                exvector v; v.reserve(num + 1);
-               numeric lcm_accum = _num1;
+               numeric lcm_accum = *_num1_p;
                for (size_t i=0; i<num; i++) {
-                       numeric op_lcm = lcmcoeff(e.op(i), _num1);
+                       numeric op_lcm = lcmcoeff(e.op(i), *_num1_p);
                        v.push_back(multiply_lcm(e.op(i), op_lcm));
                        lcm_accum *= op_lcm;
                }
@@ -310,7 +310,7 @@ numeric ex::integer_content() const
 
 numeric basic::integer_content() const
 {
-       return _num1;
+       return *_num1_p;
 }
 
 numeric numeric::integer_content() const
@@ -322,7 +322,7 @@ numeric add::integer_content() const
 {
        epvector::const_iterator it = seq.begin();
        epvector::const_iterator itend = seq.end();
-       numeric c = _num0, l = _num1;
+       numeric c = *_num0_p, l = *_num1_p;
        while (it != itend) {
                GINAC_ASSERT(!is_exactly_a<numeric>(it->rest));
                GINAC_ASSERT(is_exactly_a<numeric>(it->coeff));
@@ -730,24 +730,24 @@ static bool divide_in_z(const ex &a, const ex &b, ex &q, sym_desc_vec::const_ite
        // Compute values at evaluation points 0..adeg
        vector<numeric> alpha; alpha.reserve(adeg + 1);
        exvector u; u.reserve(adeg + 1);
-       numeric point = _num0;
+       numeric point = *_num0_p;
        ex c;
        for (i=0; i<=adeg; i++) {
                ex bs = b.subs(x == point, subs_options::no_pattern);
                while (bs.is_zero()) {
-                       point += _num1;
+                       point += *_num1_p;
                        bs = b.subs(x == point, subs_options::no_pattern);
                }
                if (!divide_in_z(a.subs(x == point, subs_options::no_pattern), bs, c, var+1))
                        return false;
                alpha.push_back(point);
                u.push_back(c);
-               point += _num1;
+               point += *_num1_p;
        }
 
        // Compute inverses
        vector<numeric> rcp; rcp.reserve(adeg + 1);
-       rcp.push_back(_num0);
+       rcp.push_back(*_num0_p);
        for (k=1; k<=adeg; k++) {
                numeric product = alpha[k] - alpha[0];
                for (i=1; i<k; i++)
@@ -1062,7 +1062,7 @@ numeric ex::max_coefficient() const
  *  @see heur_gcd */
 numeric basic::max_coefficient() const
 {
-       return _num1;
+       return *_num1_p;
 }
 
 numeric numeric::max_coefficient() const
@@ -1222,9 +1222,9 @@ static ex heur_gcd(const ex &a, const ex &b, ex *ca, ex *cb, sym_desc_vec::const
        numeric mq = q.max_coefficient();
        numeric xi;
        if (mp > mq)
-               xi = mq * _num2 + _num2;
+               xi = mq * (*_num2_p) + (*_num2_p);
        else
-               xi = mp * _num2 + _num2;
+               xi = mp * (*_num2_p) + (*_num2_p);
 
        // 6 tries maximum
        for (int t=0; t<6; t++) {
@@ -1247,11 +1247,7 @@ static ex heur_gcd(const ex &a, const ex &b, ex *ca, ex *cb, sym_desc_vec::const
                        ex dummy;
                        if (divide_in_z(p, g, ca ? *ca : dummy, var) && divide_in_z(q, g, cb ? *cb : dummy, var)) {
                                g *= gc;
-                               ex lc = g.lcoeff(x);
-                               if (is_exactly_a<numeric>(lc) && ex_to<numeric>(lc).is_negative())
-                                       return -g;
-                               else
-                                       return g;
+                               return g;
                        }
                }
 
@@ -1348,10 +1344,12 @@ factored_b:
        // Input polynomials of the form poly^n are sometimes also trivial
        if (is_exactly_a<power>(a)) {
                ex p = a.op(0);
+               const ex& exp_a = a.op(1);
                if (is_exactly_a<power>(b)) {
-                       if (p.is_equal(b.op(0))) {
+                       ex pb = b.op(0);
+                       const ex& exp_b = b.op(1);
+                       if (p.is_equal(pb)) {
                                // a = p^n, b = p^m, gcd = p^min(n, m)
-                               ex exp_a = a.op(1), exp_b = b.op(1);
                                if (exp_a < exp_b) {
                                        if (ca)
                                                *ca = _ex1;
@@ -1365,7 +1363,32 @@ factored_b:
                                                *cb = _ex1;
                                        return power(p, exp_b);
                                }
-                       }
+                       } else {
+                               ex p_co, pb_co;
+                               ex p_gcd = gcd(p, pb, &p_co, &pb_co, check_args);
+                               if (p_gcd.is_equal(_ex1)) {
+                                       // a(x) = p(x)^n, b(x) = p_b(x)^m, gcd (p, p_b) = 1 ==>
+                                       // gcd(a,b) = 1
+                                       if (ca)
+                                               *ca = a;
+                                       if (cb)
+                                               *cb = b;
+                                       return _ex1;
+                                       // XXX: do I need to check for p_gcd = -1?
+                               } else {
+                                       // there are common factors:
+                                       // a(x) = g(x)^n A(x)^n, b(x) = g(x)^m B(x)^m ==>
+                                       // gcd(a, b) = g(x)^n gcd(A(x)^n, g(x)^(n-m) B(x)^m
+                                       if (exp_a < exp_b) {
+                                               return power(p_gcd, exp_a)*
+                                                       gcd(power(p_co, exp_a), power(p_gcd, exp_b-exp_a)*power(pb_co, exp_b), ca, cb, false);
+                                       } else {
+                                               return power(p_gcd, exp_b)*
+                                                       gcd(power(p_gcd, exp_a - exp_b)*power(p_co, exp_a), power(pb_co, exp_b), ca, cb, false);
+                                       }
+                               } // p_gcd.is_equal(_ex1)
+                       } // p.is_equal(pb)
+
                } else {
                        if (p.is_equal(b)) {
                                // a = p^n, b = p, gcd = p
@@ -1374,8 +1397,24 @@ factored_b:
                                if (cb)
                                        *cb = _ex1;
                                return p;
+                       } 
+
+                       ex p_co, bpart_co;
+                       ex p_gcd = gcd(p, b, &p_co, &bpart_co, false);
+
+                       if (p_gcd.is_equal(_ex1)) {
+                               // a(x) = p(x)^n, gcd(p, b) = 1 ==> gcd(a, b) = 1
+                               if (ca)
+                                       *ca = a;
+                               if (cb)
+                                       *cb = b;
+                               return _ex1;
+                       } else {
+                               // a(x) = g(x)^n A(x)^n, b(x) = g(x) B(x) ==> gcd(a, b) = g(x) gcd(g(x)^(n-1) A(x)^n, B(x))
+                               return p_gcd*gcd(power(p_gcd, exp_a-1)*power(p_co, exp_a), bpart_co, ca, cb, false);
                        }
-               }
+               } // is_exactly_a<power>(b)
+
        } else if (is_exactly_a<power>(b)) {
                ex p = b.op(0);
                if (p.is_equal(a)) {
@@ -1386,6 +1425,23 @@ factored_b:
                                *cb = power(p, b.op(1) - 1);
                        return p;
                }
+
+               ex p_co, apart_co;
+               const ex& exp_b(b.op(1));
+               ex p_gcd = gcd(a, p, &apart_co, &p_co, false);
+               if (p_gcd.is_equal(_ex1)) {
+                       // b=p(x)^n, gcd(a, p) = 1 ==> gcd(a, b) == 1
+                       if (ca)
+                               *ca = a;
+                       if (cb)
+                               *cb = b;
+                       return _ex1;
+               } else {
+                       // there are common factors:
+                       // a(x) = g(x) A(x), b(x) = g(x)^n B(x)^n ==> gcd = g(x) gcd(g(x)^(n-1) A(x)^n, B(x))
+
+                       return p_gcd*gcd(apart_co, power(p_gcd, exp_b-1)*power(p_co, exp_b), ca, cb, false);
+               } // p_gcd.is_equal(_ex1)
        }
 #endif
 
@@ -1842,7 +1898,7 @@ static ex frac_cancel(const ex &n, const ex &d)
 {
        ex num = n;
        ex den = d;
-       numeric pre_factor = _num1;
+       numeric pre_factor = *_num1_p;
 
 //std::clog << "frac_cancel num = " << num << ", den = " << den << std::endl;