return 0;
}
+static unsigned exam_powerlaws6()
+{
+ // check expansion rules for positive symbols
+
+ symbol a("a");
+ symbol b("b");
+ symbol c("c");
+ realsymbol x("x");
+ realsymbol y("y");
+ possymbol p("p");
+ possymbol q("q");
+ numeric half=numeric(1,2);
+
+ ex e1 = pow(5*pow(3*a*b*x*y*p*q,2),7*half*c).expand();
+ ex e2 = pow(p,7*c)*pow(q,7*c)*pow(pow(a*b*x*y,2),numeric(7,2)*c)*pow(45,numeric(7,2)*c);
+ if (!e1.is_equal(e2)) {
+ clog << "Could not expand exponents with positive bases in " << e1 << endl;
+ return 1;
+ }
+
+ ex e3 = pow(-pow(-a*x*p,3)*pow(b*y*p,3),half*c).expand().normal();
+ ex e4 = pow(p,3*c)*pow(pow(a*b*x*y,3),half*c);
+
+ if (!e3.is_equal(e4)) {
+ clog << "Could not expand exponents with positive bases in " << e3 << endl;
+ return 1;
+ }
+
+ return 0;
+}
+
unsigned exam_powerlaws()
{
unsigned result = 0;
result += exam_powerlaws3(); cout << '.' << flush;
result += exam_powerlaws4(); cout << '.' << flush;
result += exam_powerlaws5(); cout << '.' << flush;
+ result += exam_powerlaws6(); cout << '.' << flush;
return result;
}
return *this;
}
+ // (x*p)^c -> x^c * p^c, if p>0
+ // makes sense before expanding the basis
+ if (is_exactly_a<mul>(basis) && !basis.info(info_flags::indefinite)) {
+ const mul &m = ex_to<mul>(basis);
+ exvector prodseq;
+ epvector powseq;
+ prodseq.reserve(m.seq.size() + 1);
+ powseq.reserve(m.seq.size() + 1);
+ epvector::const_iterator last = m.seq.end();
+ epvector::const_iterator cit = m.seq.begin();
+ bool possign = true;
+
+ // search for positive/negative factors
+ while (cit!=last) {
+ ex e=m.recombine_pair_to_ex(*cit);
+ if (e.info(info_flags::positive))
+ prodseq.push_back(pow(e, exponent).expand(options));
+ else if (e.info(info_flags::negative)) {
+ prodseq.push_back(pow(-e, exponent).expand(options));
+ possign = !possign;
+ } else
+ powseq.push_back(*cit);
+ ++cit;
+ }
+
+ // take care on the numeric coefficient
+ ex coeff=(possign? _ex1 : _ex_1);
+ if (m.overall_coeff.info(info_flags::positive) && m.overall_coeff != _ex1)
+ prodseq.push_back(power(m.overall_coeff, exponent));
+ else if (m.overall_coeff.info(info_flags::negative) && m.overall_coeff != _ex_1)
+ prodseq.push_back(power(-m.overall_coeff, exponent));
+ else
+ coeff *= m.overall_coeff;
+
+ // If positive/negative factors are found, then extract them.
+ // In either case we set a flag to avoid the second run on a part
+ // which does not have positive/negative terms.
+ if (prodseq.size() > 0) {
+ ex newbasis = coeff*mul(powseq);
+ ex_to<basic>(newbasis).setflag(status_flags::purely_indefinite);
+ return ((new mul(prodseq))->setflag(status_flags::dynallocated)*(new power(newbasis, exponent))->setflag(status_flags::dynallocated).expand(options)).expand(options);
+ } else
+ ex_to<basic>(basis).setflag(status_flags::purely_indefinite);
+ }
+
const ex expanded_basis = basis.expand(options);
const ex expanded_exponent = exponent.expand(options);