1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/utilities/numberSeq.cpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,262 @@
1.4 +/*
1.5 + * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#include "precompiled.hpp"
1.29 +#include "memory/allocation.inline.hpp"
1.30 +#include "utilities/debug.hpp"
1.31 +#include "utilities/globalDefinitions.hpp"
1.32 +#include "utilities/numberSeq.hpp"
1.33 +
1.34 +AbsSeq::AbsSeq(double alpha) :
1.35 + _num(0), _sum(0.0), _sum_of_squares(0.0),
1.36 + _davg(0.0), _dvariance(0.0), _alpha(alpha) {
1.37 +}
1.38 +
1.39 +void AbsSeq::add(double val) {
1.40 + if (_num == 0) {
1.41 + // if the sequence is empty, the davg is the same as the value
1.42 + _davg = val;
1.43 + // and the variance is 0
1.44 + _dvariance = 0.0;
1.45 + } else {
1.46 + // otherwise, calculate both
1.47 + _davg = (1.0 - _alpha) * val + _alpha * _davg;
1.48 + double diff = val - _davg;
1.49 + _dvariance = (1.0 - _alpha) * diff * diff + _alpha * _dvariance;
1.50 + }
1.51 +}
1.52 +
1.53 +double AbsSeq::avg() const {
1.54 + if (_num == 0)
1.55 + return 0.0;
1.56 + else
1.57 + return _sum / total();
1.58 +}
1.59 +
1.60 +double AbsSeq::variance() const {
1.61 + if (_num <= 1)
1.62 + return 0.0;
1.63 +
1.64 + double x_bar = avg();
1.65 + double result = _sum_of_squares / total() - x_bar * x_bar;
1.66 + if (result < 0.0) {
1.67 + // due to loss-of-precision errors, the variance might be negative
1.68 + // by a small bit
1.69 +
1.70 + // guarantee(-0.1 < result && result < 0.0,
1.71 + // "if variance is negative, it should be very small");
1.72 + result = 0.0;
1.73 + }
1.74 + return result;
1.75 +}
1.76 +
1.77 +double AbsSeq::sd() const {
1.78 + double var = variance();
1.79 + guarantee( var >= 0.0, "variance should not be negative" );
1.80 + return sqrt(var);
1.81 +}
1.82 +
1.83 +double AbsSeq::davg() const {
1.84 + return _davg;
1.85 +}
1.86 +
1.87 +double AbsSeq::dvariance() const {
1.88 + if (_num <= 1)
1.89 + return 0.0;
1.90 +
1.91 + double result = _dvariance;
1.92 + if (result < 0.0) {
1.93 + // due to loss-of-precision errors, the variance might be negative
1.94 + // by a small bit
1.95 +
1.96 + guarantee(-0.1 < result && result < 0.0,
1.97 + "if variance is negative, it should be very small");
1.98 + result = 0.0;
1.99 + }
1.100 + return result;
1.101 +}
1.102 +
1.103 +double AbsSeq::dsd() const {
1.104 + double var = dvariance();
1.105 + guarantee( var >= 0.0, "variance should not be negative" );
1.106 + return sqrt(var);
1.107 +}
1.108 +
1.109 +NumberSeq::NumberSeq(double alpha) :
1.110 + AbsSeq(alpha), _maximum(0.0), _last(0.0) {
1.111 +}
1.112 +
1.113 +bool NumberSeq::check_nums(NumberSeq *total, int n, NumberSeq **parts) {
1.114 + for (int i = 0; i < n; ++i) {
1.115 + if (parts[i] != NULL && total->num() != parts[i]->num())
1.116 + return false;
1.117 + }
1.118 + return true;
1.119 +}
1.120 +
1.121 +void NumberSeq::add(double val) {
1.122 + AbsSeq::add(val);
1.123 +
1.124 + _last = val;
1.125 + if (_num == 0) {
1.126 + _maximum = val;
1.127 + } else {
1.128 + if (val > _maximum)
1.129 + _maximum = val;
1.130 + }
1.131 + _sum += val;
1.132 + _sum_of_squares += val * val;
1.133 + ++_num;
1.134 +}
1.135 +
1.136 +
1.137 +TruncatedSeq::TruncatedSeq(int length, double alpha):
1.138 + AbsSeq(alpha), _length(length), _next(0) {
1.139 + _sequence = NEW_C_HEAP_ARRAY(double, _length, mtInternal);
1.140 + for (int i = 0; i < _length; ++i)
1.141 + _sequence[i] = 0.0;
1.142 +}
1.143 +
1.144 +TruncatedSeq::~TruncatedSeq() {
1.145 + FREE_C_HEAP_ARRAY(double, _sequence, mtGC);
1.146 +}
1.147 +
1.148 +void TruncatedSeq::add(double val) {
1.149 + AbsSeq::add(val);
1.150 +
1.151 + // get the oldest value in the sequence...
1.152 + double old_val = _sequence[_next];
1.153 + // ...remove it from the sum and sum of squares
1.154 + _sum -= old_val;
1.155 + _sum_of_squares -= old_val * old_val;
1.156 +
1.157 + // ...and update them with the new value
1.158 + _sum += val;
1.159 + _sum_of_squares += val * val;
1.160 +
1.161 + // now replace the old value with the new one
1.162 + _sequence[_next] = val;
1.163 + _next = (_next + 1) % _length;
1.164 +
1.165 + // only increase it if the buffer is not full
1.166 + if (_num < _length)
1.167 + ++_num;
1.168 +
1.169 + guarantee( variance() > -1.0, "variance should be >= 0" );
1.170 +}
1.171 +
1.172 +// can't easily keep track of this incrementally...
1.173 +double TruncatedSeq::maximum() const {
1.174 + if (_num == 0)
1.175 + return 0.0;
1.176 + double ret = _sequence[0];
1.177 + for (int i = 1; i < _num; ++i) {
1.178 + double val = _sequence[i];
1.179 + if (val > ret)
1.180 + ret = val;
1.181 + }
1.182 + return ret;
1.183 +}
1.184 +
1.185 +double TruncatedSeq::last() const {
1.186 + if (_num == 0)
1.187 + return 0.0;
1.188 + unsigned last_index = (_next + _length - 1) % _length;
1.189 + return _sequence[last_index];
1.190 +}
1.191 +
1.192 +double TruncatedSeq::oldest() const {
1.193 + if (_num == 0)
1.194 + return 0.0;
1.195 + else if (_num < _length)
1.196 + // index 0 always oldest value until the array is full
1.197 + return _sequence[0];
1.198 + else {
1.199 + // since the array is full, _next is over the oldest value
1.200 + return _sequence[_next];
1.201 + }
1.202 +}
1.203 +
1.204 +double TruncatedSeq::predict_next() const {
1.205 + if (_num == 0)
1.206 + return 0.0;
1.207 +
1.208 + double num = (double) _num;
1.209 + double x_squared_sum = 0.0;
1.210 + double x_sum = 0.0;
1.211 + double y_sum = 0.0;
1.212 + double xy_sum = 0.0;
1.213 + double x_avg = 0.0;
1.214 + double y_avg = 0.0;
1.215 +
1.216 + int first = (_next + _length - _num) % _length;
1.217 + for (int i = 0; i < _num; ++i) {
1.218 + double x = (double) i;
1.219 + double y = _sequence[(first + i) % _length];
1.220 +
1.221 + x_squared_sum += x * x;
1.222 + x_sum += x;
1.223 + y_sum += y;
1.224 + xy_sum += x * y;
1.225 + }
1.226 + x_avg = x_sum / num;
1.227 + y_avg = y_sum / num;
1.228 +
1.229 + double Sxx = x_squared_sum - x_sum * x_sum / num;
1.230 + double Sxy = xy_sum - x_sum * y_sum / num;
1.231 + double b1 = Sxy / Sxx;
1.232 + double b0 = y_avg - b1 * x_avg;
1.233 +
1.234 + return b0 + b1 * num;
1.235 +}
1.236 +
1.237 +
1.238 +// Printing/Debugging Support
1.239 +
1.240 +void AbsSeq::dump() { dump_on(gclog_or_tty); }
1.241 +
1.242 +void AbsSeq::dump_on(outputStream* s) {
1.243 + s->print_cr("\t _num = %d, _sum = %7.3f, _sum_of_squares = %7.3f",
1.244 + _num, _sum, _sum_of_squares);
1.245 + s->print_cr("\t _davg = %7.3f, _dvariance = %7.3f, _alpha = %7.3f",
1.246 + _davg, _dvariance, _alpha);
1.247 +}
1.248 +
1.249 +void NumberSeq::dump_on(outputStream* s) {
1.250 + AbsSeq::dump_on(s);
1.251 + s->print_cr("\t\t _last = %7.3f, _maximum = %7.3f", _last, _maximum);
1.252 +}
1.253 +
1.254 +void TruncatedSeq::dump_on(outputStream* s) {
1.255 + AbsSeq::dump_on(s);
1.256 + s->print_cr("\t\t _length = %d, _next = %d", _length, _next);
1.257 + for (int i = 0; i < _length; i++) {
1.258 + if (i%5 == 0) {
1.259 + s->cr();
1.260 + s->print("\t");
1.261 + }
1.262 + s->print("\t[%d]=%7.3f", i, _sequence[i]);
1.263 + }
1.264 + s->cr();
1.265 +}
