25 using namespace shogun;
27 #ifndef DOXYGEN_SHOULD_SKIP_THIS
28 struct LTSA_THREAD_PARAM
45 const int32_t* neighborhood_matrix;
62 PTHREAD_LOCK_T* W_matrix_lock;
78 return "LocalTangentSpaceAlignment";
91 pthread_t* threads =
SG_MALLOC(pthread_t, num_threads);
92 LTSA_THREAD_PARAM* parameters =
SG_MALLOC(LTSA_THREAD_PARAM, num_threads);
94 int32_t num_threads = 1;
108 PTHREAD_LOCK_T W_matrix_lock;
110 PTHREAD_LOCK_INIT(&W_matrix_lock);
111 pthread_attr_init(&attr);
112 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
114 for (t=0; t<num_threads; t++)
116 parameters[t].idx_start = t;
117 parameters[t].idx_step = num_threads;
118 parameters[t].idx_stop = N;
119 parameters[t].m_k =
m_k;
121 parameters[t].dim = dim;
123 parameters[t].neighborhood_matrix = neighborhood_matrix.
matrix;
125 parameters[t].mean_vector = mean_vector + dim*t;
126 parameters[t].local_feature_matrix = local_feature_matrix + (
m_k*dim)*t;
127 parameters[t].feature_matrix = feature_matrix.
matrix;
128 parameters[t].s_values_vector = s_values_vector + dim*t;
129 parameters[t].q_matrix = q_matrix + (
m_k*
m_k)*t;
130 parameters[t].W_matrix = W_matrix;
131 parameters[t].W_matrix_lock = &W_matrix_lock;
132 pthread_create(&threads[t], &attr,
run_ltsa_thread, (
void*)¶meters[t]);
134 for (t=0; t<num_threads; t++)
135 pthread_join(threads[t], NULL);
136 PTHREAD_LOCK_DESTROY(&W_matrix_lock);
140 LTSA_THREAD_PARAM single_thread_param;
141 single_thread_param.idx_start = 0;
142 single_thread_param.idx_step = 1;
143 single_thread_param.idx_stop = N;
144 single_thread_param.m_k =
m_k;
146 single_thread_param.dim = dim;
147 single_thread_param.N = N;
148 single_thread_param.neighborhood_matrix = neighborhood_matrix.
matrix;
149 single_thread_param.G_matrix = G_matrix;
150 single_thread_param.mean_vector = mean_vector;
151 single_thread_param.local_feature_matrix = local_feature_matrix;
152 single_thread_param.feature_matrix = feature_matrix.
matrix;
153 single_thread_param.s_values_vector = s_values_vector;
154 single_thread_param.q_matrix = q_matrix;
155 single_thread_param.W_matrix = W_matrix;
166 for (int32_t i=0; i<N; i++)
168 for (int32_t j=0; j<
m_k; j++)
169 W_matrix[N*neighborhood_matrix[j*N+i]+neighborhood_matrix[j*N+i]] += 1.0;
177 LTSA_THREAD_PARAM* parameters = (LTSA_THREAD_PARAM*)p;
178 int32_t idx_start = parameters->idx_start;
179 int32_t idx_step = parameters->idx_step;
180 int32_t idx_stop = parameters->idx_stop;
181 int32_t
m_k = parameters->m_k;
182 int32_t target_dim = parameters->target_dim;
183 int32_t dim = parameters->dim;
184 int32_t N = parameters->N;
185 const int32_t* neighborhood_matrix = parameters->neighborhood_matrix;
186 float64_t* G_matrix = parameters->G_matrix;
187 float64_t* mean_vector = parameters->mean_vector;
188 float64_t* local_feature_matrix = parameters->local_feature_matrix;
189 const float64_t* feature_matrix = parameters->feature_matrix;
190 float64_t* s_values_vector = parameters->s_values_vector;
191 float64_t* q_matrix = parameters->q_matrix;
192 float64_t* W_matrix = parameters->W_matrix;
194 PTHREAD_LOCK_T* W_matrix_lock = parameters->W_matrix_lock;
199 for (j=0; j<
m_k; j++)
202 for (i=idx_start; i<idx_stop; i+=idx_step)
205 memset(mean_vector,0,
sizeof(
float64_t)*dim);
208 for (j=0; j<
m_k; j++)
210 for (k=0; k<dim; k++)
211 local_feature_matrix[j*dim+k] = feature_matrix[neighborhood_matrix[j*N+i]*dim+k];
213 cblas_daxpy(dim,1.0,local_feature_matrix+j*dim,1,mean_vector,1);
217 cblas_dscal(dim,1.0/m_k,mean_vector,1);
220 for (j=0; j<
m_k; j++)
221 cblas_daxpy(dim,-1.0,mean_vector,1,local_feature_matrix+j*dim,1);
225 wrap_dgesvd(
'N',
'O',dim,m_k,local_feature_matrix,dim,
226 s_values_vector,NULL,1, NULL,1,&info);
229 for (j=0; j<target_dim; j++)
231 for (k=0; k<
m_k; k++)
232 G_matrix[(j+1)*m_k+k] = local_feature_matrix[k*dim+j];
236 cblas_dgemm(CblasColMajor,CblasNoTrans,CblasTrans,
237 m_k,m_k,1+target_dim,
244 PTHREAD_LOCK(W_matrix_lock);
246 for (j=0; j<
m_k; j++)
248 for (k=0; k<
m_k; k++)
249 W_matrix[N*neighborhood_matrix[k*N+i]+neighborhood_matrix[j*N+i]] -= q_matrix[j*m_k+k];
252 PTHREAD_UNLOCK(W_matrix_lock);