@@ 129-155 (lines=27) @@ | ||
126 | @see get_clusters() |
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127 | ||
128 | """ |
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129 | ||
130 | return self.__medians; |
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131 | ||
132 | ||
133 | def get_cluster_encoding(self): |
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134 | """! |
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135 | @brief Returns clustering result representation type that indicate how clusters are encoded. |
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136 | ||
137 | @return (type_encoding) Clustering result representation. |
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138 | ||
139 | @see get_clusters() |
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140 | ||
141 | """ |
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142 | ||
143 | return type_encoding.CLUSTER_INDEX_LIST_SEPARATION; |
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144 | ||
145 | ||
146 | def __update_clusters(self): |
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147 | """! |
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148 | @brief Calculate Manhattan distance to each point from the each cluster. |
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149 | @details Nearest points are captured by according clusters and as a result clusters are updated. |
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150 | ||
151 | @return (list) updated clusters as list of clusters where each cluster contains indexes of objects from data. |
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152 | ||
153 | """ |
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154 | ||
155 | clusters = [[] for i in range(len(self.__medians))]; |
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156 | for index_point in range(len(self.__pointer_data)): |
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157 | index_optim = -1; |
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158 | dist_optim = 0.0; |
@@ 361-394 (lines=34) @@ | ||
358 | ||
359 | Kw = (1.0 - K / N) * sigma_sqrt; |
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360 | Ks = ( 2.0 * alpha * sigma / (N ** 0.5) ) * ( (alpha ** 2.0) * sigma_sqrt / N + W - Kw / 2.0 ) ** 0.5; |
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361 | ||
362 | scores = sigma_sqrt * (2 * K)**0.5 * ((2 * K)**0.5 + betta) / N + W - sigma_sqrt + Ks + 2 * alpha**0.5 * sigma_sqrt / N |
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363 | ||
364 | return scores; |
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365 | ||
366 | ||
367 | def __bayesian_information_criterion(self, clusters, centers): |
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368 | """! |
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369 | @brief Calculates splitting criterion for input clusters using bayesian information criterion. |
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370 | ||
371 | @param[in] clusters (list): Clusters for which splitting criterion should be calculated. |
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372 | @param[in] centers (list): Centers of the clusters. |
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373 | ||
374 | @return (double) Splitting criterion in line with bayesian information criterion. |
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375 | High value of splitting criterion means that current structure is much better. |
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376 | ||
377 | @see __minimum_noiseless_description_length(clusters, centers) |
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378 | ||
379 | """ |
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380 | ||
381 | scores = [float('inf')] * len(clusters) # splitting criterion |
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382 | dimension = len(self.__pointer_data[0]); |
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383 | ||
384 | # estimation of the noise variance in the data set |
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385 | sigma_sqrt = 0.0; |
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386 | K = len(clusters); |
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387 | N = 0.0; |
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388 | ||
389 | for index_cluster in range(0, len(clusters), 1): |
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390 | for index_object in clusters[index_cluster]: |
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391 | sigma_sqrt += euclidean_distance_sqrt(self.__pointer_data[index_object], centers[index_cluster]); |
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392 | ||
393 | N += len(clusters[index_cluster]); |
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394 | ||
395 | if (N - K > 0): |
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396 | sigma_sqrt /= (N - K); |
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397 | p = (K - 1) + dimension * K + 1; |
@@ 126-152 (lines=27) @@ | ||
123 | #changes = max([euclidean_distance(self.__centers[index], updated_centers[index]) for index in range(len(self.__centers))]); # Slow solution |
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124 | changes = max([euclidean_distance_sqrt(self.__centers[index], updated_centers[index]) for index in range(len(updated_centers))]); # Fast solution |
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125 | ||
126 | self.__centers = updated_centers; |
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127 | ||
128 | ||
129 | def get_clusters(self): |
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130 | """! |
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131 | @brief Returns list of allocated clusters, each cluster contains indexes of objects in list of data. |
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132 | ||
133 | @see process() |
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134 | @see get_centers() |
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135 | ||
136 | """ |
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137 | ||
138 | return self.__clusters; |
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139 | ||
140 | ||
141 | def get_centers(self): |
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142 | """! |
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143 | @brief Returns list of centers of allocated clusters. |
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144 | ||
145 | @see process() |
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146 | @see get_clusters() |
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147 | ||
148 | """ |
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149 | ||
150 | return self.__centers; |
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151 | ||
152 | ||
153 | def get_cluster_encoding(self): |
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154 | """! |
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155 | @brief Returns clustering result representation type that indicate how clusters are encoded. |
@@ 146-175 (lines=30) @@ | ||
143 | return type_encoding.CLUSTER_INDEX_LIST_SEPARATION; |
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144 | ||
145 | ||
146 | def __update_clusters(self): |
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147 | """! |
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148 | @brief Calculate distance to each point from the each cluster. |
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149 | @details Nearest points are captured by according clusters and as a result clusters are updated. |
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150 | ||
151 | @return (list) updated clusters as list of clusters where each cluster contains indexes of objects from data. |
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152 | ||
153 | """ |
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154 | ||
155 | clusters = [[self.__medoid_indexes[i]] for i in range(len(self.__medoids))]; |
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156 | for index_point in range(len(self.__pointer_data)): |
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157 | if (index_point in self.__medoid_indexes): |
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158 | continue; |
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159 | ||
160 | index_optim = -1; |
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161 | dist_optim = float('Inf'); |
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162 | ||
163 | for index in range(len(self.__medoids)): |
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164 | dist = euclidean_distance_sqrt(self.__pointer_data[index_point], self.__medoids[index]); |
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165 | ||
166 | if ( (dist < dist_optim) or (index is 0)): |
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167 | index_optim = index; |
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168 | dist_optim = dist; |
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169 | ||
170 | clusters[index_optim].append(index_point); |
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171 | ||
172 | # If cluster is not able to capture object it should be removed |
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173 | clusters = [cluster for cluster in clusters if len(cluster) > 0]; |
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174 | ||
175 | return clusters; |
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176 | ||
177 | ||
178 | def __update_medoids(self): |