jiri/LA_library
1
0 Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

bugfixes in permutation

Browse Source
This commit is contained in:
jiri committed 2026-10-28 21:53:40 +01:00
1 parent 420eeedd8e
commit 63b9e8c92e
3 files changed
+28 -19
Download Patch File Download Diff File Expand all files Collapse all files

No files matched your search

permutation.cc
+20 -13
View File
@@ -110,6 +110,7 @@ return smallest;
template <typename T>
void NRPerm<T>::inverseme()
{
this->copyonwrite();
for(int i=1; i<=size(); ++i) if(cycle_leader(i)==i) reverse_cycle(i);
}
@@ -365,7 +366,7 @@ while (i < j) {
return true;
}
//Algorithm L from Knuth's volume 4
//Algorithm P (plain changes) from Knuth's volume 4; parity of the permutations alternates
template <typename T>
PERM_RANK_TYPE NRPerm<T>::generate_all(void (*callback)(const NRPerm<T>&), int select)
{
@@ -381,7 +382,7 @@ PERM_RANK_TYPE sumperm=0;
p2:
sumperm++;
if(callback) {if(!select || (select&1) == (sumperm&1)) {(*callback)(*this); this->copyonwrite();}}
if(callback) {if(!select || (select>0) == (sumperm&1)) {(*callback)(*this); this->copyonwrite();}} //odd sumperm = even permutation
j=n; s=0;
p4:
q=c[j]+d[j];
@@ -409,11 +410,12 @@ template <typename T>
static PermutationAlgebra<T,T> *list_all_return;
static PERM_RANK_TYPE list_all_index;
static int list_all_parity;
template <typename T>
static void list_all_callback(const NRPerm<T> &p)
{
(*list_all_return<T>)[list_all_index].weight= (list_all_index&1)?-1:1;
(*list_all_return<T>)[list_all_index].weight= list_all_parity? list_all_parity : ((list_all_index&1)?-1:1); //weight = parity
(*list_all_return<T>)[list_all_index].perm=p;
(*list_all_return<T>)[list_all_index].perm.copyonwrite();
++list_all_index;
@@ -427,6 +429,7 @@ if(parity_sel) number/=2;
PermutationAlgebra<T,T> ret(number);
list_all_return<T> = &ret;
list_all_index=0;
list_all_parity=parity_sel>0?1:(parity_sel<0?-1:0);
this->generate_all(list_all_callback,parity_sel);
return ret;
}
@@ -460,7 +463,7 @@ while(1)
T t;
sumperm++;
if(callback) (*callback)(*this);
if(callback) {(*callback)(*this); this->copyonwrite();}
j=this->size()-1;
while(j>0 && (*this)[j]>=(*this)[j+1]) j--;
if(j==0) break; /*finished*/
@@ -509,7 +512,7 @@ if(n<= _n<T>)
else
{
_sumperm++;
if(_callback<T>) (*_callback<T>)(*_perm<T>);
if(_callback<T>) {(*_callback<T>)(*_perm<T>); _perm<T>->copyonwrite();}
}
}
@@ -549,7 +552,7 @@ PERM_RANK_TYPE np=0;
this->identity();
do{
ret[np].perm = *this; ret[np].perm.copyonwrite();
ret[np].weight=0;
ret[np].weight=1; //unnormalized symmetrizer
++np;
}while(this->next());
return ret;
@@ -731,18 +734,19 @@ for(j=1;j<=n;++j) /*number of elements left from j bigger >j*/
}
break;
default: laerror("illegal type in inversions");
}
if(prank)
{
if(type!=3) laerror("rank can be computed from inversions only for type 3");
l=1;
*prank=0;
PERM_RANK_TYPE f=1;
for(j=1;j<n;++j)
{
l*= j;
*prank += l*i[n-j];
f*= j;
*prank += f*i[n-j];
}
}
}
return i;
}
@@ -1019,7 +1023,7 @@ CyclePerm<T> CyclePerm<T>::operator*(const CyclePerm &q) const
{
int m=this->max();
int mm=q.max();
if(mm>m) mm=m;
if(mm>m) m=mm;
NRPerm<T> qq(q,m);
NRPerm<T> pp(*this,m);
NRPerm<T> rr=pp*qq;
@@ -1045,6 +1049,7 @@ return tt*r;
template <typename T>
void CyclePerm<T>::simplify(bool keep1)
{
this->copyonwrite();
int j=0;
for(int i=1; i<=this->size(); ++i)
{
@@ -1365,7 +1370,7 @@ template <typename T>
void partgen(int remain, int pos)
{
int hi,lo;
if(remain==0) {++partitioncount; if(_pcallback<T>) (*_pcallback<T>)(*partition<T>); return;}
if(remain==0) {++partitioncount; if(_pcallback<T>) {(*_pcallback<T>)(*partition<T>); partition<T>->copyonwrite();} return;}
if(partitiontyp) lo=(remain+partitiontypabs-pos)/(partitiontypabs-pos+1); else lo=1;
hi=remain;
if(partitiontyp>0) hi -= partitiontypabs-pos;
@@ -1764,7 +1769,7 @@ if(ncyc> _ncycles<T>)
{
if(_callyoung)
{
if(_young_callback<T>) _young_callback<T>(*_tchi<T>);
if(_young_callback<T>) {_young_callback<T>(*_tchi<T>); _tchi<T>->copyonwrite();}
_character<T> ++;
}
else _character<T> += _tchi<T>->character_contribution(_ncycles<T>);
@@ -2208,11 +2213,13 @@ for(int i=1; i<ngroups; ++i) r= r&lists[i];
return r;
}
#if 0 //reminder how a member template of a class template is defined in .cc
//DOES NOT WORK template<typename T,typename U>
template<typename T> template <typename U> //this works
void NRPerm<T>::testik(U u)
{
}
#endif
/***************************************************************************//**
* forced instantization in the corresponding object file
permutation.h
+7 -5
View File
@@ -64,7 +64,7 @@ public:
bool is_identity() const;
CompressedPartition<T> cycles() const {return CyclePerm<T>(*this).cycles(size());};
NRPerm inverse() const;
void reverse_cycle(int i); //aux for inverseme
void reverse_cycle(int i); //aux for inverseme, no copyonwrite (caller's responsibility)
int cycle_leader(int i) const; //aux for inverseme
void inverseme(); //in-place
NRPerm reverse() const; //backward order
@@ -81,10 +81,12 @@ public:
int parity() const; //returns +/- 1
void randomize(void); //uniformly random by Fisher-Yates shuffle
bool next(); //generate next permutation in lex order
PERM_RANK_TYPE generate_all(void (*callback)(const NRPerm<T>&), int parity_select=0); //Algorithm L from Knuth's vol.4, efficient but not in lex order!
PERM_RANK_TYPE generate_all(void (*callback)(const NRPerm<T>&), int parity_select=0); //Algorithm P (plain changes) from Knuth's vol.4, efficient but not in lex order! parity_select +1 even, -1 odd permutations only
PermutationAlgebra<T,T> list_all(int parity_select=0);
PermutationAlgebra<T,T> list_all_lex();
#if 0 //reminder how a member template of a class template is defined in .cc
template <typename U> void testik(U u); //demostrate that in .cc one has to declare the nested templates separately
#endif
PERM_RANK_TYPE generate_all_multi(void (*callback)(const NRPerm<T>&)); //Algorithm L2 from Knuth's vol.4, for a multiset (repeated numbers, not really permutations)
PERM_RANK_TYPE generate_all2(void (*callback)(const NRPerm<T>&)); //recursive method, also not lexicographic
PERM_RANK_TYPE generate_all_lex(void (*callback)(const NRPerm<T>&)); //generate in lex order using next()
@@ -107,8 +109,8 @@ NRVec_from1<X> applypermutation(const NRPerm<T> &p, const NRVec_from1<X> &set, b
if(p.size()!=set.size()) laerror("size mismatch in applypermutation");
#endif
NRVec_from1<X> r(set.size());
if(inverse) for(int i=1; i<=p.size(); ++i) r[p[i]] = set[i];
else for(int i=1; i<=p.size(); ++i) r[i] = set[p[i]];
if(inverse) for(int i=1; i<=p.size(); ++i) r[i] = set[p[i]]; //same convention as NRVec::permuted
else for(int i=1; i<=p.size(); ++i) r[p[i]] = set[i];
return r;
}
@@ -208,7 +210,7 @@ public:
PermutationAlgebra operator|(const PermutationAlgebra &rhs) const; //each term with each
PermutationAlgebra operator*(const PermutationAlgebra &rhs) const; //each term with each
PermutationAlgebra operator+(const PermutationAlgebra &rhs) const;
PermutationAlgebra &operator*=(const R &x) {this->copyonwrite(); for(int i=1; i<=size(); ++i) (*this)[i].weight *= x; return *this;};
PermutationAlgebra &operator*=(const R &x) {this->copyonwrite(); for(int i=0; i<size(); ++i) (*this)[i].weight *= x; return *this;};
PermutationAlgebra operator*(const R &x) const {PermutationAlgebra r(*this); return r*=x;};
void simplify(const typename LA_traits<R>::normtype thr=0) {NRVec_simplify(*this,thr);};
bool operator==(PermutationAlgebra &rhs); //do NOT inherit from NRVec, as the underlying one ignores weights for the simplification; also we have to simplify before comparison
t.cc
+1 -1
View File
@@ -3157,7 +3157,7 @@ cout <<"PA = "<<a<<endl;
for(int i=0; i<a.size(); ++i)
{
cout << (a[i].weight==1?'+':'-');
NRVec_from1<INDEXNAME> pindices=applypermutation(a[i].perm,indices,false);
NRVec_from1<INDEXNAME> pindices=applypermutation(a[i].perm,indices,true);
for(int j=1; j<=pindices.size(); ++j) cout <<pindices[j];
cout <<endl;
}