int takeStep(int i, int j, F2D* a, float C, F2D* e, F2D* Y, F2D* X, float eps, float* b, int N, int dim)
{
int ret=1;
float s;
int m, n, k;
float Ei, Ej, gamma, L, H;
F2D *a_old;
float k11, k12, k22, eta;
F2D *temp, *temp1, *temp2;
float t, t1, t2;
float bnew, delta_b;
float c1, c2, Lobj, Hobj;
if(i==j)
return 0;
a_old = fDeepCopy(a);
if( asubsref(a_old,i)>0 && asubsref(a_old,i)<C )
Ei = asubsref(e,i);
else
Ei = cal_learned_func(i, a, b, N, Y, X, dim) - asubsref(Y,i);
if( asubsref(a_old,j)>0 && asubsref(a_old,j)<C )
Ej = asubsref(e,j);
else
Ej = cal_learned_func(j, a, b, N, Y, X, dim) - asubsref(Y,j);
s = asubsref(Y,i) * asubsref(Y,j);
if( asubsref(Y,i) == asubsref(Y,j) )
{
gamma = asubsref(a_old,i) + asubsref(a_old,j);
if(gamma > C)
{
L = gamma - C;
H = C;
}
else
{
L = 0;
H = gamma;
}
}
else
{
gamma = asubsref(a_old,i) - asubsref(a_old,j);
if(gamma > 0)
{
L = 0;
H = C - gamma;
}
else
{
L = -gamma;
H = C;
}
}
if(L==H)
{
fFreeHandle(a_old);
return 0;
}
temp = fMallocHandle(1, X->width);
temp1 = fMallocHandle(1, X->width);
for(m=0; m<X->width; m++)
{
asubsref(temp,m) = subsref(X,i,m);
asubsref(temp1,m) = subsref(X,j,m);
}
k11 = polynomial(3, temp, temp, dim);
k12 = polynomial(3, temp, temp1, dim);
k22 = polynomial(3, temp1, temp1, dim);
eta = 2 * k12 - k11 - k22;
fFreeHandle(temp1);
fFreeHandle(temp);
if(eta<0)
{
asubsref(a,j) = asubsref(a_old,j) + asubsref(Y,j) * (Ej-Ei)/eta;
if( asubsref(a,j) < L)
asubsref(a,j) = L;
else if( asubsref(a,j) > H )
asubsref(a,j) = H;
}
else
{
c1 = eta/2;
c2 = asubsref(Y,j) * (Ei-Ej) - eta * asubsref(a_old,j);
Lobj = c1 * L * L + c2 * L;
Hobj = c1 * H * H + c2 * H;
if (Lobj > (Hobj+eps))
asubsref(a,j) = L;
else if (Lobj < (Hobj-eps))
asubsref(a,j) = H;
else
asubsref(a,j) = asubsref(a_old,j);
}
if( fabsf( asubsref(a,j)- asubsref(a_old,j) ) < (eps* (asubsref(a,j) + asubsref(a_old,j) +eps)) )
{
fFreeHandle(a_old);
return 0;
}
asubsref(a,i) = asubsref(a_old,i) - s * ( asubsref(a,j) - asubsref(a_old,j) );
if( asubsref(a,i) < 0)
{
asubsref(a,j) = asubsref(a,j) + s * asubsref(a,i);
asubsref(a,i) = 0;
}
else if (asubsref(a,i) > C)
{
t = asubsref(a,i) - C;
asubsref(a,j) = asubsref(a,j) + s * t;
asubsref(a,i) = C;
}
/** Update threshold to react change in Lagrange multipliers **/
if( asubsref(a,i) > 0 && asubsref(a,i) < C )
bnew = arrayref(b,0) + Ei + asubsref(Y,i) * (asubsref(a,i) - asubsref(a_old,i)) * k11 + asubsref(Y,j) * (asubsref(a,j) - asubsref(a_old,j)) * k12;
else
{
if( asubsref(a,j) > 0 && asubsref(a,j) < C )
bnew = arrayref(b,0) + Ej + asubsref(Y,i) * (asubsref(a,i) - asubsref(a_old,i)) * k12 + asubsref(Y,j) * (asubsref(a,j) - asubsref(a_old,j)) * k22;
else
{
float b1, b2;
b1 = arrayref(b,0) + Ei + asubsref(Y,i) * (asubsref(a,i) - asubsref(a_old,i)) * k11 + asubsref(Y,j) * (asubsref(a,j) - asubsref(a_old,j)) * k12;
b2 = arrayref(b,0) + Ej + asubsref(Y,i) * (asubsref(a,i) - asubsref(a_old,i)) * k12 + asubsref(Y,j) * (asubsref(a,j) - asubsref(a_old,j)) * k22;
bnew = (b1 + b2) / 2;
}
}
delta_b = bnew - arrayref(b,0);
arrayref(b,0) = bnew;
/** Update error cache using new Lagrange multipliers 24ai **/
t1 = asubsref(Y,i) * (asubsref(a,i)-asubsref(a_old,i));
t2 = asubsref(Y,j) * (asubsref(a,j)-asubsref(a_old,j));
temp = fMallocHandle(1, X->width);
temp1 = fMallocHandle(1, X->width);
temp2 = fMallocHandle(1, X->width);
for (k=0; k<N; k++)
{
if (0 < asubsref(a_old,i) && asubsref(a_old,i) < C )
{
for(m=0; m<X->width; m++)
{
asubsref(temp,m) = subsref(X,i,m);
asubsref(temp1,m) = subsref(X,k,m);
asubsref(temp2,m) = subsref(X,j,m);
}
asubsref(e,k) = asubsref(e,k)+t1 * polynomial(3, temp, temp1, dim) + t2 * polynomial(3, temp2, temp1, dim) - delta_b;
asubsref(e,i) = 0;
asubsref(e,j) = 0;
}
}
fFreeHandle(a_old);
fFreeHandle(temp);
fFreeHandle(temp1);
fFreeHandle(temp2);
ret = 1;
return ret;
}
alphaRet* getAlphaFromTrainSet(int N, F2D* trn1, F2D* trn2, int iterations)
{
float tolerance, C, eps, *b;
F2D *a_result, *b_result;
int NumChanged, r, ExamineAll, cnt, d, dim, ret, iter, i;
F2D *X, *Y;
F2D *a, *e;
b = malloc(sizeof(float));
alphaRet* alpha;
alpha = (alphaRet*)malloc(sizeof(alphaRet));
tolerance = 0.001;
C = 0.05;
d = -1;
dim = 256;
eps = 0.001;
a_result = fSetArray(iterations, N, 0);
b_result = fSetArray(iterations, 1, 0);
ret = 0;
X = usps_read_partial( trn1, trn2, 0, 1, (N/iterations), iterations);
for(iter=0; iter<iterations; iter++)
{
Y = usps_read_partial( trn1, trn2, iter, 0, N/iterations, iterations);
a = fSetArray(N, 1, 0);
arrayref(b,0) = 0; /** check if ptr **/
e = fSetArray(N, 1, 0);
ExamineAll = 1;
cnt = 0;
NumChanged = 0;
while(NumChanged>0 || ExamineAll == 1)
{
cnt = cnt + 1;
NumChanged = 0;
if(ExamineAll == 1)
{
for(i=0; i<N; i++)
{
ret = examineExample(i, a, b, C, e, X, Y, tolerance, N, eps, dim);
NumChanged = NumChanged + ret;
}
}
else
{
for(i=0; i<N; i++)
{
if( asubsref(a,i) > 0 && asubsref(a,i) <C )
{
ret = examineExample(i, a, b, C, e, X, Y, tolerance, N, eps, dim);
NumChanged = NumChanged + ret;
}
}
}
if(ExamineAll == 1)
ExamineAll = 0;
else if(NumChanged == 0)
ExamineAll = 1;
}
for(r=0; r<N; r++)
subsref(a_result,iter,r) = asubsref(a,r); /** a_result has size iteration,N .. Check **/
asubsref(b_result,iter) = arrayref(b,0);
fFreeHandle(Y);
fFreeHandle(e);
fFreeHandle(a);
}
alpha->C = C;
alpha->d = d;
alpha->dim = dim;
alpha->eps = eps;
alpha->a_result = a_result;
alpha->b_result = b_result;
alpha->a = a;
alpha->b = arrayref(b,0);
alpha->X = X;
alpha->tolerance = tolerance;
alpha->ret;
free(b);
return alpha;
}
ArrayConstRef result_uref() final {
compute();
return arrayref(std17::as_const(_result));
}
