X-Git-Url: https://ginac.de/ginac.git//ginac.git?a=blobdiff_plain;f=ginac%2Fbasic.cpp;h=a2e10f715531d286c0d3fef0a0a13a4e5cc8d18a;hb=caabe6ff752d0343caff4340725352e7fbd6dc56;hp=2414c92971e99c07a8f4e91377d9afd9829d28ab;hpb=094911eb78cacb6f2877a70c9ac74766df58ccea;p=ginac.git

diff --git a/ginac/basic.cpp b/ginac/basic.cpp
index 2414c929..a2e10f71 100644
--- a/ginac/basic.cpp
+++ b/ginac/basic.cpp
@@ -21,8 +21,10 @@
  */
 
 #include <iostream>
-#include <typeinfo>
 #include <stdexcept>
+#ifdef DO_GINAC_ASSERT
+#  include <typeinfo>
+#endif
 
 #include "basic.h"
 #include "ex.h"
@@ -31,6 +33,8 @@
 #include "symbol.h"
 #include "lst.h"
 #include "ncmul.h"
+#include "relational.h"
+#include "print.h"
 #include "archive.h"
 #include "utils.h"
 #include "debugmsg.h"
@@ -89,10 +93,7 @@ basic::basic(const archive_node &n, const lst &sym_lst) : flags(0), refcount(0)
 }
 
 /** Unarchive the object. */
-ex basic::unarchive(const archive_node &n, const lst &sym_lst)
-{
-	return (new basic(n, sym_lst))->setflag(status_flags::dynallocated);
-}
+DEFAULT_UNARCHIVE(basic)
 
 /** Archive the object. */
 void basic::archive(archive_node &n) const
@@ -112,67 +113,52 @@ void basic::archive(archive_node &n) const
 
 // public
 
-/** Output to ostream formatted as parsable (as in ginsh) input.
- *  Generally, superfluous parenthesis should be avoided as far as possible. */
-void basic::print(std::ostream & os, unsigned upper_precedence) const
+/** Output to stream.
+ *  @param c print context object that describes the output formatting
+ *  @param level value that is used to identify the precedence or indentation
+ *               level for placing parentheses and formatting */
+void basic::print(const print_context & c, unsigned level) const
 {
-	debugmsg("basic print",LOGLEVEL_PRINT);
-	os << "[" << class_name() << " object]";
-}
+	debugmsg("basic print", LOGLEVEL_PRINT);
 
-/** Output to ostream in ugly raw format, so brave developers can have a look
- *  at the underlying structure. */
-void basic::printraw(std::ostream & os) const
-{
-	debugmsg("basic printraw",LOGLEVEL_PRINT);
-	os << "[" << class_name() << " object]";
-}
+	if (is_of_type(c, print_tree)) {
 
-/** Output to ostream formatted in tree- (indented-) form, so developers can
- *  have a look at the underlying structure. */
-void basic::printtree(std::ostream & os, unsigned indent) const
-{
-	debugmsg("basic printtree",LOGLEVEL_PRINT);
-	os << std::string(indent,' ') << "type=" << class_name()
-	   << ", hash=" << hashvalue
-	   << " (0x" << std::hex << hashvalue << std::dec << ")"
-	   << ", flags=" << flags
-	   << ", nops=" << nops() << std::endl;
-	for (unsigned i=0; i<nops(); ++i) {
-		op(i).printtree(os,indent+delta_indent);
-	}
-}
+		c.s << std::string(level, ' ') << class_name()
+		    << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
+		    << ", nops=" << nops()
+		    << std::endl;
+		for (unsigned i=0; i<nops(); ++i)
+			op(i).print(c, level + static_cast<const print_tree &>(c).delta_indent);
 
-/** Output to ostream formatted as C-source.
- *
- *  @param os a stream for output
- *  @param type variable type (one of the csrc_types)
- *  @param upper_precedence operator precedence of caller
- *  @see ex::printcsrc */
-void basic::printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence) const
-{
-	debugmsg("basic print csrc", LOGLEVEL_PRINT);
+	} else
+		c.s << "[" << class_name() << " object]";
 }
 
-/** Little wrapper arount print to be called within a debugger.
+/** Little wrapper around print to be called within a debugger.
  *  This is needed because you cannot call foo.print(cout) from within the
  *  debugger because it might not know what cout is.  This method can be
  *  invoked with no argument and it will simply print to stdout.
  *
- *  @see basic::print*/
+ *  @see basic::print */
 void basic::dbgprint(void) const
 {
 	this->print(std::cerr);
 	std::cerr << std::endl;
 }
 
-/** Little wrapper arount printtree to be called within a debugger.
+/** Little wrapper around printtree to be called within a debugger.
  *
  *  @see basic::dbgprint
  *  @see basic::printtree */
 void basic::dbgprinttree(void) const
 {
-	this->printtree(std::cerr,0);
+	this->print(print_tree(std::cerr));
+}
+
+/** Return relative operator precedence (for parenthizing output). */
+unsigned basic::precedence(void) const
+{
+	return 70;
 }
 
 /** Create a new copy of this on the heap.  One can think of this as simulating
@@ -227,50 +213,140 @@ ex basic::operator[](int i) const
 	return op(i);
 }
 
-/** Search ocurrences.  An object  'has' an expression if it is the expression
+/** Search ocurrences.  An object 'has' an expression if it is the expression
  *  itself or one of the children 'has' it.  As a consequence (according to
  *  the definition of children) given e=x+y+z, e.has(x) is true but e.has(x+y)
- *  is false. */
+ *  is false.  The expression can also contain wildcards. */
 bool basic::has(const ex & other) const
 {
 	GINAC_ASSERT(other.bp!=0);
-	if (is_equal(*other.bp)) return true;
-	if (nops()>0) {
-		for (unsigned i=0; i<nops(); i++)
-			if (op(i).has(other))
-				return true;
-	}
+	lst repl_lst;
+	if (match(*other.bp, repl_lst))
+		return true;
+	for (unsigned i=0; i<nops(); i++)
+		if (op(i).has(other))
+			return true;
 	
 	return false;
 }
 
-/** Return degree of highest power in symbol s. */
-int basic::degree(const symbol & s) const
+/** Construct new expression by applying the specified function to all
+ *  sub-expressions (one level only, not recursively). */
+ex basic::map(map_func f) const
+{
+	unsigned num = nops();
+	if (num == 0)
+		return *this;
+
+	basic *copy = duplicate();
+	copy->setflag(status_flags::dynallocated);
+	copy->clearflag(status_flags::hash_calculated);
+	ex e(*copy);
+	for (unsigned i=0; i<num; i++)
+		e.let_op(i) = f(e.op(i));
+	return e.eval();
+}
+
+/** Return degree of highest power in object s. */
+int basic::degree(const ex & s) const
 {
 	return 0;
 }
 
-/** Return degree of lowest power in symbol s. */
-int basic::ldegree(const symbol & s) const
+/** Return degree of lowest power in object s. */
+int basic::ldegree(const ex & s) const
 {
 	return 0;
 }
 
-/** Return coefficient of degree n in symbol s. */
-ex basic::coeff(const symbol & s, int n) const
+/** Return coefficient of degree n in object s. */
+ex basic::coeff(const ex & s, int n) const
 {
 	return n==0 ? *this : _ex0();
 }
 
-/** Sort expression in terms of powers of some symbol.
- *  @param s symbol to sort in. */
-ex basic::collect(const symbol & s) const
+/** Sort expanded expression in terms of powers of some object(s).
+ *  @param s object(s) to sort in
+ *  @param distributed recursive or distributed form (only used when s is a list) */
+ex basic::collect(const ex & s, bool distributed) const
 {
 	ex x;
-	for (int n=this->ldegree(s); n<=this->degree(s); n++)
-		x += this->coeff(s,n)*power(s,n);
+	if (is_ex_of_type(s, lst)) {
+
+		// List of objects specified
+		if (s.nops() == 1)
+			return collect(s.op(0));
+
+		else if (distributed) {
+
+			// Get lower/upper degree of all symbols in list
+			int 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 (int 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 (int i=0; i<num; i++) {
+					int cnt = si[i].cnt;
+					y *= power(si[i].sym, cnt);
+				}
+				x += y * si[num - 1].coeff;
+
+				// Increment counters
+				int 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 (int 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--;
+				}
+			}
+
+done:		delete[] si;
+
+		} else {
+
+			// Recursive form
+			x = *this;
+			for (int n=s.nops()-1; n>=0; n--)
+				x = x.collect(s[n]);
+		}
+
+	} else {
+
+		// Only one object specified
+		for (int n=this->ldegree(s); n<=this->degree(s); ++n)
+			x += this->coeff(s,n)*power(s,n);
+	}
 	
-	return x;
+	// correct for lost fractional arguments and return
+	return x + (*this - x).expand();
 }
 
 /** Perform automatic non-interruptive symbolic evaluation on expression. */
@@ -287,6 +363,15 @@ ex basic::evalf(int level) const
 	return *this;
 }
 
+/** Evaluate sums, products and integer powers of matrices. */
+ex basic::evalm(void) const
+{
+	if (nops() == 0)
+		return *this;
+	else
+		return map(GiNaC::evalm);
+}
+
 /** Perform automatic symbolic evaluations on indexed expression that
  *  contains this object as the base expression. */
 ex basic::eval_indexed(const basic & i) const
@@ -297,25 +382,126 @@ ex basic::eval_indexed(const basic & i) const
 	return i.hold();
 }
 
-/** Try to contract two indexed expressions. If a contraction exists, the
- *  function overwrites one or both arguments and returns true. Otherwise it
- *  returns false. It is guaranteed that both expressions are of class
- *  indexed (or a subclass) and that at least one dummy index has been
- *  found.
+/** Add two indexed expressions. They are guaranteed to be of class indexed
+ *  (or a subclass) and their indices are compatible. This function is used
+ *  internally by simplify_indexed().
  *
- *  @param self The first indexed expression; it's base object is *this
- *  @param other The second indexed expression
- *  @return true if the contraction was successful, false otherwise */
-bool basic::contract_with(ex & self, ex & other) const
+ *  @param self First indexed expression; it's base object is *this
+ *  @param other Second indexed expression
+ *  @return sum of self and other 
+ *  @see ex::simplify_indexed() */
+ex basic::add_indexed(const ex & self, const ex & other) const
+{
+	return self + other;
+}
+
+/** Multiply an indexed expression with a scalar. This function is used
+ *  internally by simplify_indexed().
+ *
+ *  @param self Indexed expression; it's base object is *this
+ *  @param other Numeric value
+ *  @return product of self and other
+ *  @see ex::simplify_indexed() */
+ex basic::scalar_mul_indexed(const ex & self, const numeric & other) const
+{
+	return self * other;
+}
+
+/** Try to contract two indexed expressions that appear in the same product. 
+ *  If a contraction exists, the function overwrites one or both of the
+ *  expressions and returns true. Otherwise it returns false. It is
+ *  guaranteed that both expressions are of class indexed (or a subclass)
+ *  and that at least one dummy index has been found. This functions is
+ *  used internally by simplify_indexed().
+ *
+ *  @param self Pointer to first indexed expression; it's base object is *this
+ *  @param other Pointer to second indexed expression
+ *  @param v The complete vector of factors
+ *  @return true if the contraction was successful, false otherwise
+ *  @see ex::simplify_indexed() */
+bool basic::contract_with(exvector::iterator self, exvector::iterator other, exvector & v) const
 {
 	// Do nothing
 	return false;
 }
 
-/** Substitute a set of symbols by arbitrary expressions. The ex returned
+/** 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
+{
+/*
+	Sweet sweet shapes, sweet sweet shapes,
+	That's the key thing, right right.
+	Feed feed face, feed feed shapes,
+	But who is the king tonight?
+	Who is the king tonight?
+	Pattern is the thing, the key thing-a-ling,
+	But who is the king of pattern?
+	But who is the king, the king thing-a-ling,
+	Who is the king of Pattern?
+	Bog is the king, the king thing-a-ling,
+	Bog is the king of Pattern.
+	Ba bu-bu-bu-bu bu-bu-bu-bu-bu-bu bu-bu
+	Bog is the king of Pattern.
+*/
+
+	if (is_ex_exactly_of_type(pattern, wildcard)) {
+
+		// Wildcard matches anything, but check whether we already have found
+		// a match for that wildcard first (if so, it the earlier match must
+		// be the same expression)
+		for (unsigned i=0; i<repl_lst.nops(); i++) {
+			if (repl_lst.op(i).op(0).is_equal(pattern))
+				return is_equal(*repl_lst.op(i).op(1).bp);
+		}
+		repl_lst.append(pattern == *this);
+		return true;
+
+	} else {
+
+		// Expression must be of the same type as the pattern
+		if (tinfo() != pattern.bp->tinfo())
+			return false;
+
+		// Number of subexpressions must match
+		if (nops() != pattern.nops())
+			return false;
+
+		// No subexpressions? Then just compare the objects (there can't be
+		// wildcards in the pattern)
+		if (nops() == 0)
+			return is_equal(*pattern.bp);
+
+		// Otherwise the subexpressions must match one-to-one
+		for (unsigned i=0; i<nops(); i++)
+			if (!op(i).match(pattern.op(i), repl_lst))
+				return false;
+
+		// Looks similar enough, match found
+		return true;
+	}
+}
+
+/** Substitute a set of objects by arbitrary expressions. The ex returned
  *  will already be evaluated. */
-ex basic::subs(const lst & ls, const lst & lr) const
+ex basic::subs(const lst & ls, const lst & lr, bool no_pattern) const
 {
+	GINAC_ASSERT(ls.nops() == lr.nops());
+
+	if (no_pattern) {
+		for (unsigned i=0; i<ls.nops(); i++) {
+			if (is_equal(*ls.op(i).bp))
+				return lr.op(i);
+		}
+	} else {
+		for (unsigned i=0; i<ls.nops(); i++) {
+			lst repl_lst;
+			if (match(*ls.op(i).bp, repl_lst))
+				return lr.op(i).bp->subs(repl_lst, true); // avoid infinite recursion when re-substituting the wildcards
+		}
+	}
+
 	return *this;
 }
 
@@ -370,7 +556,8 @@ ex basic::derivative(const symbol & s) const
 /** Returns order relation between two objects of same type.  This needs to be
  *  implemented by each class. It may never return anything else than 0,
  *  signalling equality, or +1 and -1 signalling inequality and determining
- *  the canonical ordering. */
+ *  the canonical ordering.  (Perl hackers will wonder why C++ doesn't feature
+ *  the spaceship operator <=> for denoting just this.) */
 int basic::compare_same_type(const basic & other) const
 {
 	return compare_pointers(this, &other);
@@ -436,15 +623,15 @@ ex basic::expand(unsigned options) const
 
 // public
 
-/** Substitute symbols in expression and return the result as a new expression.
- *  There are two valid types of replacement arguments: 1) a relational like
- *  symbol==ex and 2) a list of relationals lst(symbol1==ex1,symbol2==ex2,...),
- *  which is converted to subs(lst(symbol1,symbol2,...),lst(ex1,ex2,...)).
- *  In addition, an object of class idx can be used instead of a symbol. */
-ex basic::subs(const ex & e) const
+/** Substitute objects in an expression (syntactic substitution) and return
+ *  the result as a new expression.  There are two valid types of
+ *  replacement arguments: 1) a relational like object==ex and 2) a list of
+ *  relationals lst(object1==ex1,object2==ex2,...), which is converted to
+ *  subs(lst(object1,object2,...),lst(ex1,ex2,...)). */
+ex basic::subs(const ex & e, bool no_pattern) const
 {
 	if (e.info(info_flags::relation_equal)) {
-		return subs(lst(e));
+		return subs(lst(e), no_pattern);
 	}
 	if (!e.info(info_flags::list)) {
 		throw(std::invalid_argument("basic::subs(ex): argument must be a list"));
@@ -452,18 +639,14 @@ ex basic::subs(const ex & e) const
 	lst ls;
 	lst lr;
 	for (unsigned i=0; i<e.nops(); i++) {
-		if (!e.op(i).info(info_flags::relation_equal)) {
-			throw(std::invalid_argument("basic::subs(ex): argument must be a list or equations"));
-		}
-		if (!e.op(i).op(0).info(info_flags::symbol)) {
-			if (!e.op(i).op(0).info(info_flags::idx)) {
-				throw(std::invalid_argument("basic::subs(ex): lhs must be a symbol or an idx"));
-			}
+		ex r = e.op(i);
+		if (!r.info(info_flags::relation_equal)) {
+			throw(std::invalid_argument("basic::subs(ex): argument must be a list of equations"));
 		}
-		ls.append(e.op(i).op(0));
-		lr.append(e.op(i).op(1));
+		ls.append(r.op(0));
+		lr.append(r.op(1));
 	}
-	return subs(ls,lr);
+	return subs(ls, lr, no_pattern);
 }
 
 /** Compare objects to establish canonical ordering.
@@ -483,34 +666,36 @@ int basic::compare(const basic & other) const
 	if (typeid_this<typeid_other) {
 // 		std::cout << "hash collision, different types: " 
 // 		          << *this << " and " << other << std::endl;
-// 		this->printraw(std::cout);
+// 		this->print(print_tree(std::cout));
 // 		std::cout << " and ";
-// 		other.printraw(std::cout);
+// 		other.print(print_tree(std::cout));
 // 		std::cout << std::endl;
 		return -1;
 	}
 	if (typeid_this>typeid_other) {
 // 		std::cout << "hash collision, different types: " 
 // 		          << *this << " and " << other << std::endl;
-// 		this->printraw(std::cout);
+// 		this->print(print_tree(std::cout));
 // 		std::cout << " and ";
-// 		other.printraw(std::cout);
+// 		other.print(print_tree(std::cout));
 // 		std::cout << std::endl;
 		return 1;
 	}
 	
 	GINAC_ASSERT(typeid(*this)==typeid(other));
 	
-	int cmpval = compare_same_type(other);
-	if ((cmpval!=0) && (hash_this<0x80000000U)) {
+// 	int cmpval = compare_same_type(other);
+// 	if ((cmpval!=0) && (hash_this<0x80000000U)) {
 // 		std::cout << "hash collision, same type: " 
 // 		          << *this << " and " << other << std::endl;
-// 		this->printraw(std::cout);
+// 		this->print(print_tree(std::cout));
 // 		std::cout << " and ";
-// 		other.printraw(std::cout);
+// 		other.print(print_tree(std::cout));
 // 		std::cout << std::endl;
-	}
-	return cmpval;
+// 	}
+// 	return cmpval;
+	
+	return compare_same_type(other);
 }
 
 /** Test for equality.
@@ -547,17 +732,9 @@ void basic::ensure_if_modifiable(void) const
 {
 	if (this->refcount>1)
 		throw(std::runtime_error("cannot modify multiply referenced object"));
+	clearflag(status_flags::hash_calculated);
 }
 
-//////////
-// static member variables
-//////////
-
-// protected
-
-unsigned basic::precedence = 70;
-unsigned basic::delta_indent = 4;
-
 //////////
 // global variables
 //////////