1 files changed, 2 insertions, 114 deletions

diff --git a/web/api/queries/stddev/stddev.c b/web/api/queries/stddev/stddev.c
index 92a67b42..8f543119 100644
--- a/web/api/queries/stddev/stddev.c
+++ b/web/api/queries/stddev/stddev.c
@@ -6,123 +6,11 @@
 // ----------------------------------------------------------------------------
 // stddev
 
-// this implementation comes from:
-// https://www.johndcook.com/blog/standard_deviation/
-
-struct grouping_stddev {
-    long count;
-    NETDATA_DOUBLE m_oldM, m_newM, m_oldS, m_newS;
-};
-
-void grouping_create_stddev(RRDR *r, const char *options __maybe_unused) {
-    r->internal.grouping_data = onewayalloc_callocz(r->internal.owa, 1, sizeof(struct grouping_stddev));
-}
-
-// resets when switches dimensions
-// so, clear everything to restart
-void grouping_reset_stddev(RRDR *r) {
-    struct grouping_stddev *g = (struct grouping_stddev *)r->internal.grouping_data;
-    g->count = 0;
-}
-
-void grouping_free_stddev(RRDR *r) {
-    onewayalloc_freez(r->internal.owa, r->internal.grouping_data);
-    r->internal.grouping_data = NULL;
-}
-
-void grouping_add_stddev(RRDR *r, NETDATA_DOUBLE value) {
-    struct grouping_stddev *g = (struct grouping_stddev *)r->internal.grouping_data;
-
-    g->count++;
-
-    // See Knuth TAOCP vol 2, 3rd edition, page 232
-    if (g->count == 1) {
-        g->m_oldM = g->m_newM = value;
-        g->m_oldS = 0.0;
-    }
-    else {
-        g->m_newM = g->m_oldM + (value - g->m_oldM) / g->count;
-        g->m_newS = g->m_oldS + (value - g->m_oldM) * (value - g->m_newM);
-
-        // set up for next iteration
-        g->m_oldM = g->m_newM;
-        g->m_oldS = g->m_newS;
-    }
-}
-
-static inline NETDATA_DOUBLE mean(struct grouping_stddev *g) {
-    return (g->count > 0) ? g->m_newM : 0.0;
-}
-
-static inline NETDATA_DOUBLE variance(struct grouping_stddev *g) {
-    return ( (g->count > 1) ? g->m_newS/(NETDATA_DOUBLE)(g->count - 1) : 0.0 );
-}
-static inline NETDATA_DOUBLE stddev(struct grouping_stddev *g) {
-    return sqrtndd(variance(g));
-}
-
-NETDATA_DOUBLE grouping_flush_stddev(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
-    struct grouping_stddev *g = (struct grouping_stddev *)r->internal.grouping_data;
-
-    NETDATA_DOUBLE value;
-
-    if(likely(g->count > 1)) {
-        value = stddev(g);
-
-        if(!netdata_double_isnumber(value)) {
-            value = 0.0;
-            *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
-        }
-    }
-    else if(g->count == 1) {
-        value = 0.0;
-    }
-    else {
-        value = 0.0;
-        *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
-    }
-
-    grouping_reset_stddev(r);
-
-    return  value;
-}
-
-// https://en.wikipedia.org/wiki/Coefficient_of_variation
-NETDATA_DOUBLE grouping_flush_coefficient_of_variation(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
-    struct grouping_stddev *g = (struct grouping_stddev *)r->internal.grouping_data;
-
-    NETDATA_DOUBLE value;
-
-    if(likely(g->count > 1)) {
-        NETDATA_DOUBLE m = mean(g);
-        value = 100.0 * stddev(g) / ((m < 0)? -m : m);
-
-        if(unlikely(!netdata_double_isnumber(value))) {
-            value = 0.0;
-            *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
-        }
-    }
-    else if(g->count == 1) {
-        // one value collected
-        value = 0.0;
-    }
-    else {
-        // no values collected
-        value = 0.0;
-        *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
-    }
-
-    grouping_reset_stddev(r);
-
-    return  value;
-}
-
-
 /*
  * Mean = average
  *
 NETDATA_DOUBLE grouping_flush_mean(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
-    struct grouping_stddev *g = (struct grouping_stddev *)r->internal.grouping_data;
+    struct grouping_stddev *g = (struct grouping_stddev *)r->grouping.grouping_data;
 
     NETDATA_DOUBLE value;
 
@@ -149,7 +37,7 @@ NETDATA_DOUBLE grouping_flush_mean(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options
  * It is not advised to use this version of variance directly
  *
 NETDATA_DOUBLE grouping_flush_variance(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
-    struct grouping_stddev *g = (struct grouping_stddev *)r->internal.grouping_data;
+    struct grouping_stddev *g = (struct grouping_stddev *)r->grouping.grouping_data;
 
     NETDATA_DOUBLE value;