Created pseries::evalm. Patch by Alexei.

[ginac.git] / ginac / pseries.cpp

diff --git a/ginac/pseries.cpp b/ginac/pseries.cpp
index 14488ba71c222b81e033379d51f61be66e94b062..0e1f183322c47114404c1c4c7b502f6cc44d68f4 100644 (file)
--- a/ginac/pseries.cpp
+++ b/ginac/pseries.cpp
@@ -4,7 +4,7 @@
  *  methods for series expansion. */
 
 /*
- *  GiNaC Copyright (C) 1999-2006 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2007 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -82,14 +82,19 @@ pseries::pseries(const ex &rel_, const epvector &ops_) : basic(&pseries::tinfo_s
 
 pseries::pseries(const archive_node &n, lst &sym_lst) : inherited(n, sym_lst)
 {
-       for (unsigned int i=0; true; ++i) {
+       archive_node::archive_node_cit first = n.find_first("coeff");
+       archive_node::archive_node_cit last = n.find_last("power");
+       ++last;
+       seq.reserve((last-first)/2);
+
+       for (archive_node::archive_node_cit loc = first; loc < last;) {
                ex rest;
                ex coeff;
-               if (n.find_ex("coeff", rest, sym_lst, i) && n.find_ex("power", coeff, sym_lst, i))
-                       seq.push_back(expair(rest, coeff));
-               else
-                       break;
+               n.find_ex_by_loc(loc++, rest, sym_lst);
+               n.find_ex_by_loc(loc++, coeff, sym_lst);
+               seq.push_back(expair(rest, coeff));
        }
+
        n.find_ex("var", var, sym_lst);
        n.find_ex("point", point, sym_lst);
 }
@@ -484,6 +489,34 @@ ex pseries::eval_integ() const
        return *this;
 }
 
+ex pseries::evalm() const
+{
+       // evalm each coefficient
+       epvector newseq;
+       bool something_changed = false;
+       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+               if (something_changed) {
+                       ex newcoeff = i->rest.evalm();
+                       if (!newcoeff.is_zero())
+                               newseq.push_back(expair(newcoeff, i->coeff));
+               }
+               else {
+                       ex newcoeff = i->rest.evalm();
+                       if (!are_ex_trivially_equal(newcoeff, i->rest)) {
+                               something_changed = true;
+                               newseq.reserve(seq.size());
+                               std::copy(seq.begin(), i, std::back_inserter<epvector>(newseq));
+                               if (!newcoeff.is_zero())
+                                       newseq.push_back(expair(newcoeff, i->coeff));
+                       }
+               }
+       }
+       if (something_changed)
+               return (new pseries(var==point, newseq))->setflag(status_flags::dynallocated);
+       else
+               return *this;
+}
+
 ex pseries::subs(const exmap & m, unsigned options) const
 {
        // If expansion variable is being substituted, convert the series to a