Add support for Texinfo-5.0.
[ginac.git] / ginac / expair.h
index dd0459b..4b1a42e 100644 (file)
@@ -3,7 +3,7 @@
  *  Definition of expression pairs (building blocks of expairseq). */
 
 /*
- *  GiNaC Copyright (C) 1999-2000 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2011 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
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
-#ifndef __GINAC_EXPAIR_H__
-#define __GINAC_EXPAIR_H__
+#ifndef GINAC_EXPAIR_H
+#define GINAC_EXPAIR_H
 
 #include "ex.h"
 #include "numeric.h"
+#include "print.h"
 
-#ifndef NO_GINAC_NAMESPACE
 namespace GiNaC {
-#endif // ndef NO_GINAC_NAMESPACE
 
 /** A pair of expressions.
- *  This similar to, but slightly extended STL's pair<> but we need to account
- *  for methods like .compare() */
+ *  This is similar to STL's pair<>.  It is slightly extended since we need to
+ *  account for methods like .compare().  Also, since this is meant for use by
+ *  class expairseq it must satisfy the invariance that the member coeff must
+ *  be of type numeric. */
 class expair
 {
 public:
-    expair() {}
-    ~expair() {}
-    expair(const expair & other) : rest(other.rest), coeff(other.coeff)
-    {
-        GINAC_ASSERT(is_ex_exactly_of_type(coeff,numeric));
-    }
-    const expair & operator=(const expair & other)
-    {
-        if (this != &other) {
-            rest=other.rest;
-            coeff=other.coeff;
-        }
-        return *this;
-    }
-    expair(const ex & r, const ex & c) : rest(r), coeff(c)
-    {
-        GINAC_ASSERT(is_ex_exactly_of_type(coeff,numeric));
-    }
-    
-    bool is_numeric_with_coeff_1(void) const
-    {
-        GINAC_ASSERT(is_ex_exactly_of_type(coeff,numeric));
-        return is_ex_exactly_of_type(rest,numeric) &&
-               (coeff.is_equal(ex(1)));
-    }
-
-    bool is_equal(const expair & other) const
-    {
-        return (rest.is_equal(other.rest) && coeff.is_equal(other.coeff));
-    }
-    bool is_less(const expair & other) const 
-    {
-        return (rest.compare(other.rest)<0) ||
-               (!(other.rest.compare(rest)<0) && (coeff.compare(other.coeff)<0));
-    }
-    int compare(const expair & other) const
-    {
-        int cmpval=rest.compare(other.rest);
-        if (cmpval!=0) return cmpval;
-        cmpval=coeff.compare(other.coeff);
-        return cmpval;
-    }
-
-    bool is_less_old2(const expair & other) const 
-    {
-        /*
-        bool this_numeric_with_coeff_1=is_numeric_with_coeff_1();
-        bool other_numeric_with_coeff_1=other.is_numeric_with_coeff_1();
-        if (this_numeric_with_coeff_1) {
-            if (other_numeric_with_coeff_1) {
-                // both have coeff 1: compare rests
-                return rest.compare(other.rest)<0;
-            }
-            // only this has coeff 1: >
-            return false;
-        } else if (other_numeric_with_coeff_1) {
-            // only other has coeff 1: <
-            return true;
-        }
-        return (rest.compare(other.rest)<0) ||
-               (!(other.rest.compare(rest)<0) &&
-                 (coeff.compare(other.coeff)<0));
-        */
-        if (is_ex_exactly_of_type(rest,numeric) &&
-            is_ex_exactly_of_type(other.rest,numeric)) {
-            if (coeff.is_equal(ex(1))) {
-                if ((other.coeff).is_equal(ex(1))) {
-                    // both have coeff 1: compare rests
-                    return rest.compare(other.rest)<0;
-                }
-                // only this has coeff 1: >
-                return false;
-            } else if ((other.coeff).is_equal(ex(1))) {
-                // only other has coeff 1: <
-                return true;
-            }
-            // neither has coeff 1: usual compare        
-        }
-        return (rest.compare(other.rest)<0) ||
-               (!(other.rest.compare(rest)<0) &&
-                 (coeff.compare(other.coeff)<0));
-    }
-    int compare_old2(const expair & other) const
-    {
-        if (is_ex_exactly_of_type(rest,numeric) &&
-            is_ex_exactly_of_type(other.rest,numeric)) {
-            if ((coeff).is_equal(ex(1))) {
-                if ((other.coeff).is_equal(ex(1))) {
-                    // both have coeff 1: compare rests
-                    return rest.compare(other.rest);
-                }
-                // only this has coeff 1: >
-                return 1;
-            } else if ((other.coeff).is_equal(ex(1))) {
-                // only other has coeff 1: <
-                return -1;
-            }
-            // neither has coeff 1: usual compare        
-        }
-        /*
-        bool this_numeric_with_coeff_1=is_numeric_with_coeff_1();
-        bool other_numeric_with_coeff_1=other.is_numeric_with_coeff_1();
-        if (this_numeric_with_coeff_1) {
-            if (other_numeric_with_coeff_1) {
-                // both have coeff 1: compare rests
-                return rest.compare(other.rest);
-            }
-            // only this has coeff 1: >
-            return 1;
-        } else if (other_numeric_with_coeff_1) {
-            // only other has coeff 1: <
-            return -1;
-            // neither has coeff 1: usual compare        
-        }
-        */
-        int cmpval=rest.compare(other.rest);
-        if (cmpval!=0) return cmpval;
-        return coeff.compare(other.coeff);
-    }
-    bool is_less_old(const expair & other) const 
-    {
-        return (rest.compare(other.rest)<0) ||
-               (!(other.rest.compare(rest)<0) && (coeff.compare(other.coeff)<0));
-    }
-    int compare_old(const expair & other) const
-    {
-        int cmpval=rest.compare(other.rest);
-        if (cmpval!=0) return cmpval;
-        cmpval=coeff.compare(other.coeff);
-        return cmpval;
-    }
-
-    void printraw(ostream & os) const
-    {
-        os << "expair(";
-        rest.printraw(os);
-        os << ",";
-        coeff.printraw(os);
-        os << ")";
-    }
-
-    ex rest;
-    ex coeff;
+       expair() : rest(0), coeff(1) { }
+
+       /** Construct an expair from two ex. */
+       expair(const ex & r, const ex & c) : rest(r), coeff(c)
+       {
+               GINAC_ASSERT(is_exactly_a<numeric>(coeff));
+       }
+       
+       /** Member-wise check for canonical ordering equality. */
+       bool is_equal(const expair & other) const
+       {
+               return (rest.is_equal(other.rest) && coeff.is_equal(other.coeff));
+       }
+       
+       /** Member-wise check for canonical ordering lessness. */
+       bool is_less(const expair & other) const 
+       {
+               int restcmp = rest.compare(other.rest);
+               return ((restcmp<0) ||
+                       (!(restcmp>0) && (coeff.compare(other.coeff)<0)));
+       }
+       
+       /** Member-wise check for canonical ordering. */
+       int compare(const expair & other) const
+       {
+               int restcmp = rest.compare(other.rest);
+               if (restcmp!=0)
+                       return restcmp;
+               else
+                       return coeff.compare(other.coeff);
+       }
+       
+       void print(std::ostream & os) const;
+       
+       /** True if this is of the form (numeric,ex(1)). */
+       bool is_canonical_numeric() const
+       {
+               GINAC_ASSERT(is_exactly_a<numeric>(coeff));
+               return (is_exactly_a<numeric>(rest) && (coeff.is_equal(1)));
+       }
+
+       /** Swap contents with other expair. */
+       void swap(expair & other)
+       {
+               rest.swap(other.rest);
+               coeff.swap(other.coeff);
+       }
+
+       const expair conjugate() const;
+
+       ex rest;    ///< first member of pair, an arbitrary expression
+       ex coeff;   ///< second member of pair, must be numeric
 };
 
-class expair_is_less
-{
-public:
-    bool operator()(const expair & lh, const expair & rh) const
-    {
-        return lh.is_less(rh);
-    }
+/** Function object for insertion into third argument of STL's sort() etc. */
+struct expair_is_less : public std::binary_function<expair, expair, bool> {
+       bool operator()(const expair &lh, const expair &rh) const { return lh.is_less(rh); }
 };
 
-class expair_is_less_old
-{
-public:
-    bool operator()(const expair & lh, const expair & rh) const
-    {
-        return lh.is_less_old(rh);
-    }
+/** Function object not caring about the numerical coefficients for insertion
+ *  into third argument of STL's sort().  Note that this does not define a
+ *  strict weak ordering since for any symbol x we have neither 3*x<2*x or
+ *  2*x<3*x.  Handle with care! */
+struct expair_rest_is_less : public std::binary_function<expair, expair, bool> {
+       bool operator()(const expair &lh, const expair &rh) const { return (lh.rest.compare(rh.rest)<0); }
+};
+
+struct expair_swap : public std::binary_function<expair, expair, void> {
+       void operator()(expair &lh, expair &rh) const { lh.swap(rh); }
 };
 
-#ifndef NO_GINAC_NAMESPACE
+inline void swap(expair & e1, expair & e2)
+{ e1.swap(e2); }
+
+// This makes STL algorithms use the more efficient swap operation for ex objects
+inline void iter_swap(std::vector<expair>::iterator i1, std::vector<expair>::iterator i2)
+{ i1->swap(*i2); }
+
 } // namespace GiNaC
-#endif // ndef NO_GINAC_NAMESPACE
 
-#endif // ndef __GINAC_EXPAIR_H__
+#endif // ndef GINAC_EXPAIR_H