1 /*
2    Copyright (C) 2003-2006 MySQL AB, 2009 Sun Microsystems, Inc.
3     Use is subject to license terms.
4 
5    This program is free software; you can redistribute it and/or modify
6    it under the terms of the GNU General Public License, version 2.0,
7    as published by the Free Software Foundation.
8 
9    This program is also distributed with certain software (including
10    but not limited to OpenSSL) that is licensed under separate terms,
11    as designated in a particular file or component or in included license
12    documentation.  The authors of MySQL hereby grant you an additional
13    permission to link the program and your derivative works with the
14    separately licensed software that they have included with MySQL.
15 
16    This program is distributed in the hope that it will be useful,
17    but WITHOUT ANY WARRANTY; without even the implied warranty of
18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19    GNU General Public License, version 2.0, for more details.
20 
21    You should have received a copy of the GNU General Public License
22    along with this program; if not, write to the Free Software
23    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
24 */
25 
26 #ifndef NDBT_STATS_HPP
27 #define NDBT_STATS_HPP
28 
29 #include <ndb_global.h>
30 
31 class NDBT_Stats {
32 public:
NDBT_Stats()33   NDBT_Stats() { reset(); }
34 
reset()35   void reset() { sum = sum2 = 0.0; max = DBL_MIN; ; min = DBL_MAX; n = 0;}
36 
addObservation(double t)37   void addObservation(double t) {
38     sum+= t;
39     sum2 += (t*t);
40     n++;
41     if(min > t) min = t;
42     if(max < t) max = t;
43   }
44 
addObservation(Uint64 t)45   void addObservation(Uint64 t) { addObservation(double(t)); }
46 
getMean() const47   double getMean() const { return sum/n;}
getStddev() const48   double getStddev() const { return sqrt(getVariance()); }
getVariance() const49   double getVariance() const { return (n*sum2 - (sum*sum))/(n*n);}
getMin() const50   double getMin() const { return min;}
getMax() const51   double getMax() const { return max;}
getCount() const52   int    getCount() const { return n;}
53 
operator +=(const NDBT_Stats & c)54   NDBT_Stats & operator+=(const NDBT_Stats & c){
55     sum += c.sum;
56     sum2 += c.sum2;
57     n += c.n;
58     if(min > c.min) min = c.min;
59     if(max < c.max) max = c.max;
60     return * this;
61   }
62 private:
63   double sum;
64   double sum2;
65   int n;
66   double min, max;
67 };
68 
69 #endif
70