Zabbix

/*

** Copyright (C) 2001-2025 Zabbix SIA

**

** This program is free software: you can redistribute it and/or modify it under the terms of

** the GNU Affero General Public License as published by the Free Software Foundation, version 3.

**

** This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

** without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

** See the GNU Affero General Public License for more details.

**

** You should have received a copy of the GNU Affero General Public License along with this program.

** If not, see <https://www.gnu.org/licenses/>.

**/

​

#include "anomalystl.h"

​

#include "zbxnum.h"

#include "zbxeval.h"

#include "zbxtime.h"

​

ZBX_PTR_VECTOR_DECL(VV, zbx_vector_history_record_t *)

ZBX_PTR_VECTOR_IMPL(VV, zbx_vector_history_record_t *)

​

/*******************************************************************************

 *                                                                             *

 * Purpose: finds how many values in stl remainder are outliers.               *

 *                                                                             *

 * Parameters:  remainder        - [IN] stl remainder values vector            *

 *              deviations_count - [IN] how much a value can be away from the  *

 *                                      (mad, stdevsamp or stdevpop) to get    *

 *                                      counted as an outlier                  *

 *                        devalg - [IN] function (mad, stdevsamp or stdevpop)  *

 *                                      to evaluate a single deviation unit    *

 *           detect_period_start - [IN] evaluate number of deviations in       *

 *                                      remainder starting from this time      *

 *                 detect_period - [IN] evaluate number of deviations in       *

 *                                      remainder until this time              *

 *                        result - [OUT] result - double, a percentage how     *

 *                                       many outliers are in remainder        *

 *                         error - [OUT] the error message                     *

 *                                                                             *

 * Return value: SUCCEED - evaluated successfully, 'result' contains new value *

 *               FAIL - evaluation failed, 'result' contains old value         *

 *                                                                             *

 *******************************************************************************/

int zbx_get_percentage_of_deviations_in_stl_remainder(const zbx_vector_history_record_t *remainder,

        double deviations_count, const char* devalg, int detect_period_start, int detect_period_end,

        double *result, char **error)

{

    int         i, total_values_count = 0, deviations_detected_count = 0, ret = FAIL;

    double          remainder_deviation, deviation_limit;

    zbx_statistical_func_t  stat_func;

    zbx_vector_dbl_t    remainder_values_dbl;

​

    zbx_vector_dbl_create(&remainder_values_dbl);

​

    if (0 == remainder->values_num)

    {

        *error = zbx_strdup(*error, "empty remainder");

        goto out;

    }

​

    if (0 == strcmp("mad", devalg))

    {

        stat_func = zbx_eval_calc_mad;

    }

    else if (0 == strcmp("stddevpop", devalg))

    {

        stat_func = zbx_eval_calc_stddevpop;

    }

    else if (0 == strcmp("stddevsamp", devalg))

    {

        stat_func = zbx_eval_calc_stddevsamp;

    }

    else

    {

        *error = zbx_dsprintf(*error, "undefined devalg parameter: \"%s\"", devalg);

        THIS_SHOULD_NEVER_HAPPEN;

        goto out;

    }

​

    zbx_vector_dbl_reserve(&remainder_values_dbl, (size_t)remainder->values_num);

​

    for (i = 0; i < remainder->values_num; i++)

        zbx_vector_dbl_append(&remainder_values_dbl, remainder->values[i].value.dbl);

​

    if (SUCCEED != (ret = stat_func(&remainder_values_dbl, &remainder_deviation, error)))

        goto out;

​

    deviation_limit = remainder_deviation * deviations_count;

​