Add DSP code to filter data, allowing for integration/differentiation

[fw/altos] / ao-tools / lib / cc-analyse.c

diff --git a/ao-tools/lib/cc-analyse.c b/ao-tools/lib/cc-analyse.c
index fc8a8417bd3d6cba210be05eccea23ac0ede12d9..0e020115affe54ca6017bb010785808ee21bce0c 100644 (file)
--- a/ao-tools/lib/cc-analyse.c
+++ b/ao-tools/lib/cc-analyse.c
@@ -16,6 +16,7 @@
  */
 
 #include "cc.h"
+#include <math.h>
 
 int
 cc_timedata_min(struct cc_timedata *d, double min_time, double max_time)
@@ -56,3 +57,59 @@ cc_timedata_max(struct cc_timedata *d, double min_time, double max_time)
                        }
        return max_i;
 }
+
+int
+cc_perioddata_min(struct cc_perioddata *d, double min_time, double max_time)
+{
+       int     start, stop;
+       int     i;
+       double  min;
+       int     min_i;
+
+       if (d->num == 0)
+               return -1;
+       start = (int) ceil((min_time - d->start) / d->step);
+       if (start < 0)
+               start = 0;
+       stop = (int) floor((max_time - d->start) / d->step);
+       if (stop >= d->num)
+               stop = d->num - 1;
+       if (stop < start)
+               return -1;
+       min = d->data[start];
+       min_i = start;
+       for (i = start + 1; i <= stop; i++)
+               if (d->data[i] < min) {
+                       min = d->data[i];
+                       min_i = i;
+               }
+       return min_i;
+}
+
+int
+cc_perioddata_max(struct cc_perioddata *d, double min_time, double max_time)
+{
+       int     start, stop;
+       int     i;
+       double  max;
+       int     max_i;
+
+       if (d->num == 0)
+               return -1;
+       start = (int) ceil((min_time - d->start) / d->step);
+       if (start < 0)
+               start = 0;
+       stop = (int) floor((max_time - d->start) / d->step);
+       if (stop >= d->num)
+               stop = d->num - 1;
+       if (stop < start)
+               return -1;
+       max = d->data[start];
+       max_i = start;
+       for (i = start + 1; i <= stop; i++)
+               if (fabs(d->data[i]) > max) {
+                       max = fabs(d->data[i]);
+                       max_i = i;
+               }
+       return max_i;
+}