X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fbasic.cpp;h=e8c893ba26dd59a963e00fd1056daf34f4f47bf8;hp=38219dcd029274b1d82ad733bccb13f4ffa339ba;hb=a377cee53b71348235ec36f83afeced7e10288a8;hpb=5a8b8e3c4d882249db35b679ce3144a59a7012e8

diff --git a/ginac/basic.cpp b/ginac/basic.cpp
index 38219dcd..e8c893ba 100644
--- a/ginac/basic.cpp
+++ b/ginac/basic.cpp
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's ABC. */
 
 /*
- *  GiNaC Copyright (C) 1999-2006 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2008 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
@@ -30,6 +30,7 @@
 #include "ex.h"
 #include "numeric.h"
 #include "power.h"
+#include "add.h"
 #include "symbol.h"
 #include "lst.h"
 #include "ncmul.h"
@@ -38,6 +39,7 @@
 #include "wildcard.h"
 #include "archive.h"
 #include "utils.h"
+#include "inifcns.h"
 
 namespace GiNaC {
 
@@ -288,7 +290,7 @@ ex & basic::operator[](size_t i)
  *  but e.has(x+y) is false. */
 bool basic::has(const ex & pattern, unsigned options) const
 {
-	lst repl_lst;
+	exmap repl_lst;
 	if (match(pattern, repl_lst))
 		return true;
 	for (size_t i=0; i<nops(); i++)
@@ -325,6 +327,12 @@ ex basic::map(map_function & f) const
 		return *this;
 }
 
+/** Check whether this is a polynomial in the given variables. */
+bool basic::is_polynomial(const ex & var) const
+{
+	return !has(var) || is_equal(ex_to<basic>(var));
+}
+
 /** Return degree of highest power in object s. */
 int basic::degree(const ex & s) const
 {
@@ -362,56 +370,32 @@ ex basic::collect(const ex & s, bool distributed) const
 
 		else if (distributed) {
 
-			// Get lower/upper degree of all symbols in list
-			size_t num = s.nops();
-			struct sym_info {
-				ex sym;
-				int ldeg, deg;
-				int cnt;  // current degree, 'counter'
-				ex coeff; // coefficient for degree 'cnt'
-			};
-			sym_info *si = new sym_info[num];
-			ex c = *this;
-			for (size_t i=0; i<num; i++) {
-				si[i].sym = s.op(i);
-				si[i].ldeg = si[i].cnt = this->ldegree(si[i].sym);
-				si[i].deg = this->degree(si[i].sym);
-				c = si[i].coeff = c.coeff(si[i].sym, si[i].cnt);
-			}
-
-			while (true) {
-
-				// Calculate coeff*x1^c1*...*xn^cn
-				ex y = _ex1;
-				for (size_t i=0; i<num; i++) {
-					int cnt = si[i].cnt;
-					y *= power(si[i].sym, cnt);
-				}
-				x += y * si[num - 1].coeff;
-
-				// Increment counters
-				size_t n = num - 1;
-				while (true) {
-					++si[n].cnt;
-					if (si[n].cnt <= si[n].deg) {
-						// Update coefficients
-						ex c;
-						if (n == 0)
-							c = *this;
-						else
-							c = si[n - 1].coeff;
-						for (size_t i=n; i<num; i++)
-							c = si[i].coeff = c.coeff(si[i].sym, si[i].cnt);
-						break;
-					}
-					if (n == 0)
-						goto done;
-					si[n].cnt = si[n].ldeg;
-					n--;
+			x = this->expand();
+			if (! is_a<add>(x))
+				return x; 
+			const lst& l(ex_to<lst>(s));
+
+			exmap cmap;
+			cmap[_ex1] = _ex0;
+			for (const_iterator xi=x.begin(); xi!=x.end(); ++xi) {
+				ex key = _ex1;
+				ex pre_coeff = *xi;
+				for (lst::const_iterator li=l.begin(); li!=l.end(); ++li) {
+					int cexp = pre_coeff.degree(*li);
+					pre_coeff = pre_coeff.coeff(*li, cexp);
+					key *= pow(*li, cexp);
 				}
+				exmap::iterator ci = cmap.find(key);
+				if (ci != cmap.end())
+					ci->second += pre_coeff;
+				else
+					cmap.insert(exmap::value_type(key, pre_coeff));
 			}
 
-done:		delete[] si;
+			exvector resv;
+			for (exmap::const_iterator mi=cmap.begin(); mi != cmap.end(); ++mi)
+				resv.push_back((mi->first)*(mi->second));
+			return (new add(resv))->setflag(status_flags::dynallocated);
 
 		} else {
 
@@ -550,9 +534,9 @@ bool basic::contract_with(exvector::iterator self, exvector::iterator other, exv
 }
 
 /** Check whether the expression matches a given pattern. For every wildcard
- *  object in the pattern, an expression of the form "wildcard == matching_expression"
- *  is added to repl_lst. */
-bool basic::match(const ex & pattern, lst & repl_lst) const
+ *  object in the pattern, a pair with the wildcard as a key and matching 
+ *  expression as a value is added to repl_lst. */
+bool basic::match(const ex & pattern, exmap& repl_lst) const
 {
 /*
 	Sweet sweet shapes, sweet sweet shapes,
@@ -575,11 +559,11 @@ bool basic::match(const ex & pattern, lst & repl_lst) const
 		// Wildcard matches anything, but check whether we already have found
 		// a match for that wildcard first (if so, the earlier match must be
 		// the same expression)
-		for (lst::const_iterator it = repl_lst.begin(); it != repl_lst.end(); ++it) {
-			if (it->op(0).is_equal(pattern))
-				return is_equal(ex_to<basic>(it->op(1)));
+		for (exmap::const_iterator it = repl_lst.begin(); it != repl_lst.end(); ++it) {
+			if (it->first.is_equal(pattern))
+				return is_equal(ex_to<basic>(it->second));
 		}
-		repl_lst.append(pattern == *this);
+		repl_lst[pattern] = *this;
 		return true;
 
 	} else {
@@ -601,12 +585,18 @@ bool basic::match(const ex & pattern, lst & repl_lst) const
 		if (!match_same_type(ex_to<basic>(pattern)))
 			return false;
 
+		// Even if the expression does not match the pattern, some of
+		// its subexpressions could match it. For example, x^5*y^(-1)
+		// does not match the pattern $0^5, but its subexpression x^5
+		// does. So, save repl_lst in order to not add bogus entries.
+		exmap tmp_repl = repl_lst;
 		// Otherwise the subexpressions must match one-to-one
 		for (size_t i=0; i<nops(); i++)
-			if (!op(i).match(pattern.op(i), repl_lst))
+			if (!op(i).match(pattern.op(i), tmp_repl))
 				return false;
 
 		// Looks similar enough, match found
+		repl_lst = tmp_repl;
 		return true;
 	}
 }
@@ -624,9 +614,10 @@ ex basic::subs_one_level(const exmap & m, unsigned options) const
 		return thisex;
 	} else {
 		for (it = m.begin(); it != m.end(); ++it) {
-			lst repl_lst;
+			exmap repl_lst;
 			if (match(ex_to<basic>(it->first), repl_lst))
-				return it->second.subs(repl_lst, options | subs_options::no_pattern); // avoid infinite recursion when re-substituting the wildcards
+				return it->second.subs(repl_lst, options | subs_options::no_pattern);
+			// avoid infinite recursion when re-substituting the wildcards
 		}
 	}
 
@@ -705,6 +696,16 @@ ex basic::conjugate() const
 	return *this;
 }
 
+ex basic::real_part() const
+{
+	return real_part_function(*this).hold();
+}
+
+ex basic::imag_part() const
+{
+	return imag_part_function(*this).hold();
+}
+
 ex basic::eval_ncmul(const exvector & v) const
 {
 	return hold_ncmul(v);
@@ -775,9 +776,9 @@ unsigned basic::return_type() const
 	return return_types::commutative;
 }
 
-const basic* basic::return_type_tinfo() const
+tinfo_t basic::return_type_tinfo() const
 {
-	return this;
+	return tinfo_key;
 }
 
 /** Compute the hash value of an object and if it makes sense to store it in