* prepare for landing of version 0.7.3.

[ginac.git] / ginac / pseries.cpp

diff --git a/ginac/pseries.cpp b/ginac/pseries.cpp
index d447aaa64de9d98e135beb67ec7e32a03509cc62..78986b4da5da2939ce86c39f9a7961f389d8117a 100644 (file)
--- a/ginac/pseries.cpp
+++ b/ginac/pseries.cpp
@@ -132,20 +132,15 @@ void pseries::archive(archive_node &n) const
 // functions overriding virtual functions from bases classes
 //////////
 
-basic *pseries::duplicate() const
-{
-       debugmsg("pseries duplicate", LOGLEVEL_DUPLICATE);
-       return new pseries(*this);
-}
-
 void pseries::print(std::ostream &os, unsigned upper_precedence) const
 {
        debugmsg("pseries print", LOGLEVEL_PRINT);
        if (precedence<=upper_precedence) os << "(";
+       // objects of type pseries must not have any zero entries, so the
+       // trivial (zero) pseries needs a special treatment here:
+       if (seq.size()==0)
+               os << '0';
        for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
-               // omit zero terms
-               if (i->rest.is_zero())
-                       continue;
                // print a sign, if needed
                if (i!=seq.begin())
                        os << '+';
@@ -183,9 +178,8 @@ void pseries::printraw(std::ostream &os) const
 {
        debugmsg("pseries printraw", LOGLEVEL_PRINT);
        os << "pseries(" << var << ";" << point << ";";
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i)
                os << "(" << (*i).rest << "," << (*i).coeff << "),";
-       }
        os << ")";
 }
 
@@ -207,6 +201,31 @@ void pseries::printtree(std::ostream & os, unsigned indent) const
        point.printtree(os, indent+delta_indent);
 }
 
+int pseries::compare_same_type(const basic & other) const
+{
+       GINAC_ASSERT(is_of_type(other, pseries));
+       const pseries &o = static_cast<const pseries &>(other);
+
+       int cmpval = var.compare(o.var);
+       if (cmpval)
+               return cmpval;
+       cmpval = point.compare(o.point);
+       if (cmpval)
+               return cmpval;
+
+       epvector::const_iterator it1 = seq.begin(), it2 = o.seq.begin(), it1end = seq.end(), it2end = o.seq.end();
+       while ((it1 != it1end) && (it2 != it2end)) {
+               cmpval = it1->compare(*it2);
+               if (cmpval)
+                       return cmpval;
+               it1++; it2++;
+       }
+       if (it1 == it1end)
+               return it2 == it2end ? 0 : -1;
+
+       return 0;
+}
+
 /** Return the number of operands including a possible order term. */
 unsigned pseries::nops(void) const
 {
@@ -283,6 +302,13 @@ int pseries::ldegree(const symbol &s) const
        }
 }
 
+/** Return coefficient of degree n in power series if s is the expansion
+ *  variable.  If the expansion point is nonzero, by definition the n=1
+ *  coefficient in s of a+b*(s-z)+c*(s-z)^2+Order((s-z)^3) is b (assuming
+ *  the expansion took place in the s in the first place).
+ *  If s is not the expansion variable, an attempt is made to convert the
+ *  series to a polynomial and return the corresponding coefficient from
+ *  there. */
 ex pseries::coeff(const symbol &s, int n) const
 {
        if (var.is_equal(s)) {
@@ -314,7 +340,7 @@ ex pseries::coeff(const symbol &s, int n) const
                return convert_to_poly().coeff(s, n);
 }
 
-
+/** Does nothing. */
 ex pseries::collect(const symbol &s) const
 {
        return *this;
@@ -390,9 +416,11 @@ ex pseries::subs(const lst & ls, const lst & lr) const
 ex pseries::expand(unsigned options) const
 {
        epvector newseq;
-       newseq.reserve(seq.size());
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i)
-               newseq.push_back(expair(i->rest.expand(), i->coeff));
+       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+               ex restexp = i->rest.expand();
+               if (!restexp.is_zero())
+                       newseq.push_back(expair(restexp, i->coeff));
+       }
        return (new pseries(relational(var,point), newseq))
                ->setflag(status_flags::dynallocated | status_flags::expanded);
 }