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+/**
+ *    Copyright (C) 2022-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include "mongo/db/exec/sbe/abt/sbe_abt_test_util.h"
+#include "mongo/db/exec/sbe/values/value.h"
+#include "mongo/db/query/ce/histogram_predicate_estimation.h"
+#include "mongo/db/query/stats/array_histogram.h"
+#include "mongo/db/query/stats/scalar_histogram.h"
+#include "mongo/db/query/stats/value_utils.h"
+
+namespace mongo::stats {
+
+/**
+    Given a list of SBE values and a query, create a collection containing the data,
+    and count the results from the supplied query.
+ */
+size_t getActualCard(OperationContext* opCtx,
+                     const std::vector<SBEValue>& input,
+                     const std::string& query);
+
+/**
+    Given a value and a comparison operator, generate a match expression reflecting
+    x cmpOp val.
+*/
+std::string makeMatchExpr(const SBEValue& val, optimizer::ce::EstimationType cmpOp);
+
+/**
+    Given a vector of values, create a histogram reflection the distribution of the vector
+    with the supplied number of buckets.
+*/
+ScalarHistogram makeHistogram(std::vector<SBEValue>& randData, size_t nBuckets);
+
+/**
+    Serialize a vector of values.
+*/
+std::string printValueArray(const std::vector<SBEValue>& values);
+
+/**
+    Plot a set of statistics as stored in ArrayHistogram.
+*/
+std::string plotArrayEstimator(const ArrayHistogram& estimator, const std::string& header);
+
+}  // namespace mongo::stats