quantium.cpp

   1 #include <iostream>
   2 #include <string>
   3 #include <math.h>
   4 #include <fstream>
   5 #define PI 3.141592653
   6
   7 class Complex{
   8 public:
   9 Complex();                                        //Default constructor~Complex();//Default destructor.
  10 void Set(double new_real,double new_imaginary);    //Set data members.
  11 double Real();                                    //Return the real part.
  12 double Imaginary();//Return the imaginary part.
  13 Complex operator+(Complex);//Overloaded+operator
  14 Complex operator*(Complex);//Overloaded*operator
  15 Complex operator=(Complex);//Overloaded=operator
  16 int operator==(Complex);//Overloaded==operator
  17 private:
  18 double real;
  19 double imaginary;
  20 };
  21
  22
  23 class Qubit{
  24 public:
  25 Qubit();//Default constructor.
  26 ~Qubit();//Default destructor.
  27 int Measure();//Returns zero_state=0 or one_state=1 in accordanc
  28 //with the probabilities of zero_state and one_state
  29 void Dump();//Prints our zero_state,and one_state,without
  30 //disturbing anything,this operation has no physic
  31 //realization,it is only for information and debugin
  32 //It should never be used in an algorithm for
  33 //information.
  34 void SetState(Complex zero_prob,Complex one_prob);
  35 //Takes two complex numbers and sets the states t
  36 //those values.
  37 void SetAverage();//Sets the state to 2^(1/2)zero_state,2^(1/2)
  38 //one_state.No imaginary/phase component.
  39 double MCC(int state);//Multiply the zero or one state by its complex
  40 //conjugate,and return the value.This valu
  41 //will always be a real number,with no imagi
  42 //component.
  43 private:
  44 Complex zero_state;
  45 //The probability of finding the Qubit in the zero or all imarinary
  46 //state.I currently use only the real portion.
  47 Complex one_state;
  48 //The probability of finding the Qubit in the one or all real state.//I currently use only the real portion.
  49 //|zero_state|^2+|one_state|^2 should always be 1.
  50 //This notation means z_s*ComplexConjugate(z_s)+o_s*
  51 //ComplexConjugate(o_s)=1.
  52 };
  53
  54 class QuReg{
  55 public:
  56 QuReg(int size);
  57 QuReg();//Default Constructor
  58 QuReg(const QuReg&);//Copy constructor
  59 ~QuReg();//Default destructor.
  60 int DecMeasure();//Measures our quantum register,and returns the
  61 void Dump(int verbose);
  62 void SetState(Complex new_state[]);
  63 void SetAverage(int number);
  64 void Norm();
  65 Complex GetProb(int state);
  66 //Return the size of the register.
  67 int Size();
  68 private:
  69 int reg_size;
  70 Complex*State;
  71 };
  72
  73 int GetQ(int n)
  74 {
  75 int power=8;//265 is the smallest q ever is.
  76 while(pow(2,power)<pow(n,2))
  77 {
  78 power=power+1;
  79 }
  80 return((int)pow(2,power));
  81 }
  82
  83
  84
  85 int modexp(int x,int a,int n)
  86 {
  87 int value=1;int tmp;
  88 tmp=x%n;
  89 while(a>0)
  90 {
  91 if(a&1)
  92 {
  93 value=(value*tmp)%n;
  94 }
  95 tmp=tmp*tmp%n;
  96 a=a>>1;
  97 }
  98 return value;
  99 }
 100
 101
 102 int RegSize(int a){
 103 int size=0;
 104 while(a!=0){
 105 a=a>>1;
 106 size++;
 107 }
 108 return(size);
 109 }
 110
 111
 112
 113 int Max(int a,int b)
 114 {
 115 return(a>b?a:b);
 116 }
 117
 118
 119
 120 int GCD(int a,int b)
 121 {
 122 int d;
 123 if(b!=0)
 124 {
 125 while(a%b!=0)
 126 {
 127 d=a%b;
 128 a=b;
 129 b=d;
 130 }
 131 }
 132 else
 133 {
 134 return-1;
 135 }
 136 return(b);
 137 }
 138
 139
 140 void DFT(QuReg*reg,int q)
 141 {
 142 Complex*init=new Complex[q];
 143 Complex tmpcomp;
 144 tmpcomp.Set(0,0);
 145 int count=0;
 146 double tmpreal=0;
 147 double tmpimag=0;
 148 double tmpprob=0;
 149 for(int a=0;a<q;a++){
 150 if((pow(reg->GetProb(a).Real(),2)+pow(reg->GetProb(a).Imaginary(),2))>pow(10,-14))
 151 {
 152 for(int c=0;c<q;c++)
 153 {
 154 tmpcomp.Set(pow(q,-.5)*cos(2*PI*a*c/q),pow(q,-.5)*sin(2*PI*a*c/q));
 155 init[c]=init[c]+(reg->GetProb(a)*tmpcomp);
 156 }
 157 }
 158 count++;
 159 if(count==100)
 160 {
 161
 162
 163 cout<<"Making progress in Fourier transform,"<<100*((double)a/(double)(q-1))
 164 <<"%done!"<<endl<<flush;
 165 count=0;
 166 }
 167 }
 168 reg->SetState(init);
 169 reg->Norm();
 170 delete[]init;
 171 }