Storage and fast transpose of matrices

#include <iostream> #include <vector> #include <string>using namespace std;// Ternary Group template<class t>struct triple{size_t _row;size_t _col; t _value;}; Template<class t>class sparsematrix{public:sparsematrix (); Sparsematrix (T* a,size_t row,size_t col,const t& invalid); Sparsematrix (CONST&NBSP;SPARSEMATRIX&LT;T&GT;&AMP;&NBSP;SM); Sparsematrix<t>& operator= (CONST&NBSP;SPARSEMATRIX&LT;T&GT;&AMP;&NBSP;SM); ~SparseMatrix (); void  display (); Sparsematrix& transpose (); Sparsematrix& fasttranspose ();p rivate:vector<triple<t>> _array;size_t _rowsize; size_t _colsize; t _invalid;}; Template<class t>sparsematrix<t>::sparsematrix (): _rowsize (0), _colsize (0), _invalid (0) {} Template<class t>sparsematrix<t>::sparsematrix (T* a,size_t row,size_t col, Const t& invalid): _rowsize (Row), _colsize (col), _Invalid (invalid) {for (size_t i=0;i<_rowsize;i++) {for (size_t j=0;j<_colsize;j++) {if (a[i*_colsize +j]!=_invalid) {triple<t> t;t._row=i;t._col=j;t._value=a[i*_colsize+j];_array.push_back (T);}}}} Template<class t>sparsematrix<t>::sparsematrix (CONST&NBSP;SPARSEMATRIX&LT;T&GT;&AMP;&NBSP;SM) : _rowsize (Sm._rowsize), _colsize (sm._colsize), _invalid (Sm._invalid) {for (size_t i=0;i<sm._array.size (); I + +) {_array.push_back (sm._array[i]);}} Template<class t>sparsematrix<t>& sparsematrix<t>::operator= (const  SPARSEMATRIX&LT;T&GT;&AMP;&NBSP;SM) {_rowsize=sm._rowsize;_colsize=sm._colsize;_invalid=sm._invalid;for (size_t  i=0;i<_sm.array.size (; i++)) {_array.push_back (sm._array[i]);} Return *this;} Template<class t>sparsematrix<t>::~sparsematrix () {}template<class t>void  Sparsematrix<t>::D isplay () {size_t index=0;for (size_t i=0;i<_rowsize;i++) {for (size_t j= 0;j<_colsize;j++) {if (Index<_array.size () && (_array[index]._row==i) && (_array[index]._col==j)) {cout <<_array[index]._value;index++;} Else{cout<<_invalid;} cout<< " ";} Cout<<endl;} Cout<<endl;} General Transpose Template<class t>sparsematrix<t>& sparsematrix<t>::transpose () { Sparsematrix<t> sm; for (size_t i=0;i<_colsize;i++)  {for (size_t index=0;index <_array.size (); index++) {if (_array[index]._col==i) {triple<t> t;t._row=_array[index]._col;t._col=_ Array[index]._row;t._value=_array[index]._value;sm._array.push_back (t);}}  }swap (Sm._array,_array); swap (_rowsize,_colsize); return *this;} Quick Transpose Template<class t>sparsematrix<t>& sparsematrix<t>:: fasttranspose () { int* rowcounts=new int[_colsize];//counts the number of data per row after transpose  //2 0 2 0 2 int*  rowstart=new int[_colsize];//statistics the size of the starting position of each row of data after the transpose//  new  whyIt's _colsize, must it be him?   //Yes, explain  0 2 2 4 4 memset in the following example (Rowcounts,0,sizeof ( int) *_colsize);  //Initialize  rowcounts memset (rowstart,0,sizeof (int) *_colsize);  for (size_t  Index=0;index<_array.size (); index++)  { rowcounts[_array[index]._col]++; }  //initialization  rowstart rowstart[0]=0; for (size_t index=1;index<_colsize;index++)  {  Rowstart[index]= rowstart[index-1]+rowcounts[index-1]; } rowstart[0]=0; for (Int index =0;index<_array.size (); index++)  { triple<t> t; t._row=_array[index]._col; t. _col=_array[index]._row; t._value=_array[index]._value; }return *this;} Void test1 () {int a[]={1,0,3,0,5,0,0,0,0,0,0,0,0,0,0,1,0,3,0,5,0,0,0,0,0,0,0,0,0,0,0,}; SPARSEMATRIX&LT;INT&GT;&NBSP;SM1 (a,6,5,0); sm1. Display (); SPARSEMATRIX&LT;INT&GT;SM2 (SM1); sm2. Display (); SPARSEMATRIX&LT;INT&GT;SM3=SM1;SM3. Display ();} Void test2 () {int a[6][5]={{1,0,3,0,5},{0,0,0,0,0},{0,0,0,0,0},{1,0,3,0,5},{0,0,0,0,0},{0,0,0,0,0}}; SPARSEMATRIX&LT;INT&GT;&NBSP;SM1 (a[0],6,5,0); sm1. Display (); Sparsematrix<int> sm2=sm1. Transpose (); sm2. Display (); Sparsematrix<int> sm3=sm1. Fasttranspose (); sm3. Display ();} Int main () {//test1 (); Test2 (); System ("pause"); return 0;}

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Storage and fast transpose of matrices