diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/km-solve.c | 37 | ||||
| -rw-r--r-- | src/km.h | 5 |
2 files changed, 9 insertions, 33 deletions
diff --git a/src/km-solve.c b/src/km-solve.c index f579a41..4730eb4 100644 --- a/src/km-solve.c +++ b/src/km-solve.c @@ -5,7 +5,7 @@ #include "util.h" #include "km.h" -#define MIN_CLUSTER_DISTANCE 0.00001 +#define MIN_DELTA 0.00001 // alloc and initialize row map static km_row_map_t * @@ -142,38 +142,21 @@ km_solve( if (cbs && cbs->on_stats) { float sum = 0, - silouette = 0, - mean_dists[num_clusters], - mean_nears[num_clusters]; - - memset(mean_dists, 0, sizeof(mean_dists)); - memset(mean_nears, 0, sizeof(mean_nears)); - - // calculate sum of distances across all clusters - for (size_t i = 0; i < set->num_rows; i++) { - sum += row_map[i].d2; - } + silouette = 0; // calculate mean numerators and silouette for (size_t i = 0; i < set->num_rows; i++) { - // distance squared (d2) to center of this cluster - mean_dists[row_map[i].cluster] += row_map[i].d2; - - // distance squared (d2) to center of nearest cluster - mean_nears[row_map[i].cluster] += row_map[i].d2_near; + // sum distances + sum += row_map[i].d2; // calculate silouette denominator // (https://en.wikipedia.org/wiki/Silhouette_%28clustering%29) - const float delta = row_map[i].d2_near - row_map[i].d2; - if (fabsf(delta) > MIN_CLUSTER_DISTANCE) { - silouette += delta / MAX(row_map[i].d2, row_map[i].d2_near); - } - } + const float delta = (row_map[i].d2_near - row_map[i].d2); - // finalize means (divide by row count) - for (size_t i = 0; i < num_clusters; i++) { - mean_dists[i] = (cs->ints[i]) ? (sqrt(mean_dists[i]) / cs->ints[i]) : 0; - mean_nears[i] = (cs->ints[i]) ? (sqrt(mean_nears[i]) / cs->ints[i]) : 0; + // sum silouette + silouette += (delta < -MIN_DELTA || delta > MIN_DELTA) + ? (delta / MAX(row_map[i].d2, row_map[i].d2_near)) + : 0.0; } // finalize silouette @@ -183,8 +166,6 @@ km_solve( const km_solve_stats_t stats = { .sum = sum, .silouette = silouette, - .mean_dists = mean_dists, - .mean_nears = mean_nears, .num_clusters = num_clusters, }; @@ -94,12 +94,7 @@ typedef struct { typedef struct { const float sum; - const float silouette; - - const float *mean_dists; - const float *mean_nears; - const size_t num_clusters; } km_solve_stats_t; |