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-rw-r--r--web/api/queries/stddev/stddev.h120
1 files changed, 0 insertions, 120 deletions
diff --git a/web/api/queries/stddev/stddev.h b/web/api/queries/stddev/stddev.h
deleted file mode 100644
index f7a1a06c..00000000
--- a/web/api/queries/stddev/stddev.h
+++ /dev/null
@@ -1,120 +0,0 @@
-// SPDX-License-Identifier: GPL-3.0-or-later
-
-#ifndef NETDATA_API_QUERIES_STDDEV_H
-#define NETDATA_API_QUERIES_STDDEV_H
-
-#include "../query.h"
-#include "../rrdr.h"
-
-// this implementation comes from:
-// https://www.johndcook.com/blog/standard_deviation/
-
-struct tg_stddev {
- long count;
- NETDATA_DOUBLE m_oldM, m_newM, m_oldS, m_newS;
-};
-
-static inline void tg_stddev_create(RRDR *r, const char *options __maybe_unused) {
- r->time_grouping.data = onewayalloc_callocz(r->internal.owa, 1, sizeof(struct tg_stddev));
-}
-
-// resets when switches dimensions
-// so, clear everything to restart
-static inline void tg_stddev_reset(RRDR *r) {
- struct tg_stddev *g = (struct tg_stddev *)r->time_grouping.data;
- g->count = 0;
-}
-
-static inline void tg_stddev_free(RRDR *r) {
- onewayalloc_freez(r->internal.owa, r->time_grouping.data);
- r->time_grouping.data = NULL;
-}
-
-static inline void tg_stddev_add(RRDR *r, NETDATA_DOUBLE value) {
- struct tg_stddev *g = (struct tg_stddev *)r->time_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 tg_stddev_mean(struct tg_stddev *g) {
- return (g->count > 0) ? g->m_newM : 0.0;
-}
-
-static inline NETDATA_DOUBLE tg_stddev_variance(struct tg_stddev *g) {
- return ( (g->count > 1) ? g->m_newS/(NETDATA_DOUBLE)(g->count - 1) : 0.0 );
-}
-static inline NETDATA_DOUBLE tg_stddev_stddev(struct tg_stddev *g) {
- return sqrtndd(tg_stddev_variance(g));
-}
-
-static inline NETDATA_DOUBLE tg_stddev_flush(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
- struct tg_stddev *g = (struct tg_stddev *)r->time_grouping.data;
-
- NETDATA_DOUBLE value;
-
- if(likely(g->count > 1)) {
- value = tg_stddev_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;
- }
-
- tg_stddev_reset(r);
-
- return value;
-}
-
-// https://en.wikipedia.org/wiki/Coefficient_of_variation
-static inline NETDATA_DOUBLE tg_stddev_coefficient_of_variation_flush(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
- struct tg_stddev *g = (struct tg_stddev *)r->time_grouping.data;
-
- NETDATA_DOUBLE value;
-
- if(likely(g->count > 1)) {
- NETDATA_DOUBLE m = tg_stddev_mean(g);
- value = 100.0 * tg_stddev_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;
- }
-
- tg_stddev_reset(r);
-
- return value;
-}
-
-#endif //NETDATA_API_QUERIES_STDDEV_H