#include "test.h"

#include "iqtensor.h"

using namespace itensor;

using namespace std;

TEST_CASE("Homepage")

{

Index a("a",2), b("b",2), c("c",2);

ITensor Z(a,b), X(b,c);

commaInit(Z,a,b) << 1, 0,

0, -1;

commaInit(X,b,c) << 0, 1,

1, 0;

ITensor R = Z * X;

CHECK_CLOSE(R(a(1),c(1)),0,1E-10);

CHECK_CLOSE(R(a(1),c(2)),+1,1E-10);

CHECK_CLOSE(R(a(2),c(1)),-1,1E-10);

CHECK_CLOSE(R(a(2),c(2)),0,1E-10);

}

TEST_CASE("TutorialIntro")

{

//cout << "Begin: TutorialIntro -----------------------" << endl;

Index i("i",10), j("j",20), k("k",30);

ITensor A(i,j), B(j,k), C;

A(i(2),j(1)) = 0.5;

A(i(1),j(2)) = 0.5;

B(j(1),k(1)) = 1;

B(j(1),k(1)) = -1;

C = A * B;

//PrintDat(C);

//cout << "End: TutorialIntro -----------------------" << endl;

}

TEST_CASE("TutorialSimpleMeasurement")

{

Index s("s",2,Site);

ITensor ket(s);

Real theta = Pi/4;

ket(s(1)) = cos(theta/2);

ket(s(2)) = sin(theta/2);

ITensor Sz(s,prime(s)),

Sx(s,prime(s));

commaInit(Sz,s,prime(s)) << 0.5, 0,

0, -0.5;

commaInit(Sx,s,prime(s)) << 0, 0.5,

0.5, 0;

ITensor bra = dag(prime(ket));

Real zz = (bra * Sz * ket).toReal();

Real xx = (bra * Sx * ket).toReal();

CHECK_CLOSE(zz,0.5*sin(Pi/4),1E-5);

CHECK_CLOSE(xx,0.5*sin(Pi/4),1E-5);

//println("<Sz> = ",zz);

//println("<Sx> = ",xx);

}