1 files changed, 49 insertions, 0 deletions
diff --git a/src/util.h b/src/util.h
new file mode 100644
index 0000000..821c3e6
--- /dev/null
+++ b/src/util.h
@@ -0,0 +1,49 @@
+#ifndef UTIL_H
+#define UTIL_H
+
+#include <stdio.h> // fprintf()
+#include <stdlib.h> // exit()
+
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define UNUSED(a) ((void) (a))
+
+#define D(...) do { \
+  fprintf(stderr, "DEBUG: %s(): ", __func__); \
+  fprintf(stderr, __VA_ARGS__); \
+  fputs("\n", stderr); \
+} while (0)
+
+#define die(...) do { \
+  fputs("FATAL: ", stderr); \
+  fprintf(stderr, __VA_ARGS__); \
+  fputs("\n", stderr); \
+  exit(EXIT_FAILURE); \
+} while (0)
+
+// calculate squared euclidean distance between two points
+static inline float
+distance_squared(
+  const size_t num_floats,
+  const float * const a,
+  const float * const b
+) {
+  float r = 0.0;
+
+  for (size_t i = 0; i < num_floats; i++) {
+    r += (b[i] - a[i]) * (b[i] - a[i]);
+  }
+
+  // return squared distance
+  return r;
+}
+
+static inline float
+km_score(
+  const float mean_distance,
+  const size_t num_empty
+) {
+  return 1.0 / (mean_distance + num_empty);
+}
+
+#endif /* UTIL_H */