*** empty log message ***

bitvector.cc

@@ -10,8 +10,131 @@ return s;
 istream & operator>>(istream  &s, bitvector &x)
 {
 bool a;
+x.copyonwrite();
 for(unsigned int i=0; i<x.size(); ++i) {s >>a; x.assign(i,a);}
 return s;
 }
 
 
+//implemented so that vectors of different length are considered different automatically
+bool bitvector::operator!=(const bitvector &rhs) const
+{
+if(nn!=rhs.nn || modulo!=rhs.modulo) return 1;
+if(v==rhs.v) return 0;
+if(!modulo) return memcmp(v,rhs.v,nn*sizeof(bitvector_block));
+if(memcmp(v,rhs.v,(nn-1)*sizeof(bitvector_block))) return 1;
+bitvector_block a=v[nn-1];
+bitvector_block b=rhs.v[nn-1];
+//zero out the irrelevant bits
+bitvector_block mask= ~((bitvector_block)0);
+mask <<=modulo;
+mask = ~mask;
+a&=mask; b&=mask;
+return a!=b;
+}
+
+
+bool bitvector::operator>(const bitvector &rhs) const
+{
+if(nn!=rhs.nn || modulo!=rhs.modulo) laerror("at the moment only bitvectors of the same length comparable");
+if(v==rhs.v) return 0;
+if(!modulo) return memcmp(v,rhs.v,nn*sizeof(bitvector_block)>0);
+int r;
+if((r=memcmp(v,rhs.v,(nn-1)*sizeof(bitvector_block)))) return r>0;
+bitvector_block a=v[nn-1];
+bitvector_block b=rhs.v[nn-1];
+//zero out the irrelevant bits
+bitvector_block mask= ~((bitvector_block)0);
+mask <<=modulo;
+mask = ~mask;
+a&=mask; b&=mask;
+return a>b;
+}
+
+bool bitvector::operator<(const bitvector &rhs) const
+{
+if(nn!=rhs.nn || modulo!=rhs.modulo) laerror("at the moment only bitvectors of the same length comparable");
+if(v==rhs.v) return 0;
+if(!modulo) return memcmp(v,rhs.v,nn*sizeof(bitvector_block)<0);
+int r;
+if((r=memcmp(v,rhs.v,(nn-1)*sizeof(bitvector_block)))) return r<0;
+bitvector_block a=v[nn-1];
+bitvector_block b=rhs.v[nn-1];
+//zero out the irrelevant bits
+bitvector_block mask= ~((bitvector_block)0);
+mask <<=modulo;
+mask = ~mask;
+a&=mask; b&=mask;
+return a<b;
+}
+
+
+
+bitvector bitvector::operator~() const
+{
+bitvector r((*this).size());
+for(int i=0; i<nn; ++i) r.v[i] = ~v[i];
+return r;
+}
+
+bitvector& bitvector::operator&=(const bitvector &rhs)
+{
+#ifdef DEBUG
+if(nn!=rhs.nn || modulo!=rhs.modulo) laerror("operation on incompatible bitvectors");
+#endif
+copyonwrite();
+for(int i=0; i<nn; ++i) v[i] &= rhs.v[i];
+return *this;
+}
+
+bitvector& bitvector::operator|=(const bitvector &rhs)
+{
+#ifdef DEBUG
+if(nn!=rhs.nn || modulo!=rhs.modulo) laerror("operation on incompatible bitvectors");
+#endif
+copyonwrite();
+for(int i=0; i<nn; ++i) v[i] |= rhs.v[i];
+return *this;
+}
+
+bitvector& bitvector::operator^=(const bitvector &rhs)
+{
+#ifdef DEBUG
+if(nn!=rhs.nn || modulo!=rhs.modulo) laerror("operation on incompatible bitvectors");
+#endif
+copyonwrite();
+for(int i=0; i<nn; ++i) v[i] ^= rhs.v[i];
+return *this;
+}
+
+
+/*number of ones in a binary number, from "Hacker's delight" book*/
+#ifdef LONG_IS_32 
+static unsigned long word_popul(unsigned long x) 
+{
+x -= ((x>>1)&0x55555555);
+x = (x&0x33333333) + ((x>>2)&0x33333333);
+x=(x + (x>>4))&0x0f0f0f0f;
+x+= (x>>8);
+x+= (x>>16);
+return x&0x3f;
+}
+#endif
+
+
+unsigned int bitvector::population(const unsigned int before) const
+{
+//@@@before
+int i;
+unsigned int s=0;
+for(i=0; i<nn-1; ++i) s+=word_popul(v[i]);
+bitvector_block a=v[nn-1];
+if(modulo)
+	{
+	bitvector_block mask= ~((bitvector_block)0);
+	mask <<=modulo;
+	a &= ~mask;
+	}
+return s+word_popul(a);
+}
+

bitvector.h

@@ -23,7 +23,8 @@ public:
 	bitvector() : NRVec<bitvector_block>() {};
 	explicit bitvector (const unsigned int n):NRVec<bitvector_block>((n+blockbits-1)/blockbits) {modulo=n%blockbits;};
 	bitvector (const bitvector_block a, const unsigned int n):NRVec<bitvector_block>(a,(n+blockbits-1)/blockbits) {modulo=n%blockbits;};
-	bitvector(const bitvector &rhs) : NRVec<bitvector_block>(rhs) {};
+	bitvector(const bitvector &rhs) : NRVec<bitvector_block>(rhs) {modulo=rhs.modulo;};
+	//operator= seems to be correctly synthetized by the compiler
 	//override dereferencing to address single bits, is however possible
 	//only in the const context (otherwise we would have to define a type which, when assigned to, changes a single bit - possible but probably inefficient)
 	void resize(const unsigned int n) {NRVec<bitvector_block>::resize((n+blockbits-1)/blockbits); modulo=n%blockbits;};
@@ -36,8 +37,23 @@ public:
 	const bool assign(const unsigned int i, const bool r) {if(r) set(i); else reset(i); return r;};
 	void clear() {memset(v,0,nn*sizeof(bitvector_block));};
 	void fill() {memset(v,0xff,nn*sizeof(bitvector_block));};
-	const bool operator!=(const bitvector &rhs) const {};
-	const bool operator==(const bitvector &rhs) const {return !(*this != rhs);};
+	bool operator!=(const bitvector &rhs) const;
+	bool operator==(const bitvector &rhs) const {return !(*this != rhs);};
+	bool operator>(const bitvector &rhs) const;
+	bool operator<(const bitvector &rhs) const;
+	bool operator>=(const bitvector &rhs) const {return !(*this < rhs);};
+	bool operator<=(const bitvector &rhs) const {return !(*this > rhs);};
+	bitvector operator~() const;
+	bitvector& operator&=(const bitvector &rhs);
+	bitvector& operator|=(const bitvector &rhs);
+	bitvector& operator^=(const bitvector &rhs);
+	bitvector operator&(const bitvector &rhs) const {return bitvector(*this) &= rhs;};
+	bitvector operator|(const bitvector &rhs) const {return bitvector(*this) |= rhs;};
+	bitvector operator^(const bitvector &rhs) const {return bitvector(*this) ^= rhs;};
+	unsigned int population(const unsigned int before=0) const; //@@@number of 1's
+	//extended, truncated const i.e. not on *this but return new entity, take care of modulo's bits
+	//logical shifts  <<= >>= << >> not implemented yet
+	//logical rotations not implemented yet
 	};