rtc_tools/rtc_event_log_visualizer/plot_base.cc - src - Git at Google

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */

 #include "rtc_tools/rtc_event_log_visualizer/plot_base.h"

 #include <algorithm>
 #include <memory>

 #include "rtc_base/checks.h"

 namespace webrtc {

 void Plot::SetXAxis(float min_value,
                     float max_value,
                     std::string label,
                     float left_margin,
                     float right_margin) {
   RTC_DCHECK_LE(min_value, max_value);
   xaxis_min_ = min_value - left_margin * (max_value - min_value);
   xaxis_max_ = max_value + right_margin * (max_value - min_value);
   xaxis_label_ = label;
 }

 void Plot::SetSuggestedXAxis(float min_value,
                              float max_value,
                              std::string label,
                              float left_margin,
                              float right_margin) {
   for (const auto& series : series_list_) {
     for (const auto& point : series.points) {
       min_value = std::min(min_value, point.x);
       max_value = std::max(max_value, point.x);
     }
   }
   SetXAxis(min_value, max_value, label, left_margin, right_margin);
 }

 void Plot::SetYAxis(float min_value,
                     float max_value,
                     std::string label,
                     float bottom_margin,
                     float top_margin) {
   RTC_DCHECK_LE(min_value, max_value);
   yaxis_min_ = min_value - bottom_margin * (max_value - min_value);
   yaxis_max_ = max_value + top_margin * (max_value - min_value);
   yaxis_label_ = label;
 }

 void Plot::SetSuggestedYAxis(float min_value,
                              float max_value,
                              std::string label,
                              float bottom_margin,
                              float top_margin) {
   for (const auto& series : series_list_) {
     for (const auto& point : series.points) {
       min_value = std::min(min_value, point.y);
       max_value = std::max(max_value, point.y);
     }
   }
   SetYAxis(min_value, max_value, label, bottom_margin, top_margin);
 }

 void Plot::SetYAxisTickLabels(
     const std::vector<std::pair<float, std::string>>& labels) {
   yaxis_tick_labels_ = labels;
 }

 void Plot::SetTitle(const std::string& title) {
   title_ = title;
 }

 void Plot::SetId(const std::string& id) {
   id_ = id;
 }

 void Plot::AppendTimeSeries(TimeSeries&& time_series) {
   series_list_.emplace_back(std::move(time_series));
 }

 void Plot::AppendIntervalSeries(IntervalSeries&& interval_series) {
   interval_list_.emplace_back(std::move(interval_series));
 }

 void Plot::AppendTimeSeriesIfNotEmpty(TimeSeries&& time_series) {
   if (!time_series.points.empty()) {
     series_list_.emplace_back(std::move(time_series));
   }
 }

 void Plot::PrintPythonCode() const {
   // Write python commands to stdout. Intended program usage is
   // ./event_log_visualizer event_log160330.dump | python

   if (!series_list_.empty()) {
     printf("color_count = %zu\n", series_list_.size());
     printf(
         "hls_colors = [(i*1.0/color_count, 0.25+i*0.5/color_count, 0.8) for i "
         "in range(color_count)]\n");
     printf("colors = [colorsys.hls_to_rgb(*hls) for hls in hls_colors]\n");

     for (size_t i = 0; i < series_list_.size(); i++) {
       printf("\n# === Series: %s ===\n", series_list_[i].label.c_str());
       // List x coordinates
       printf("x%zu = [", i);
       if (!series_list_[i].points.empty())
         printf("%.3f", series_list_[i].points[0].x);
       for (size_t j = 1; j < series_list_[i].points.size(); j++)
         printf(", %.3f", series_list_[i].points[j].x);
       printf("]\n");

       // List y coordinates
       printf("y%zu = [", i);
       if (!series_list_[i].points.empty())
         printf("%G", series_list_[i].points[0].y);
       for (size_t j = 1; j < series_list_[i].points.size(); j++)
         printf(", %G", series_list_[i].points[j].y);
       printf("]\n");

       if (series_list_[i].line_style == LineStyle::kBar) {
         // There is a plt.bar function that draws bar plots,
         // but it is *way* too slow to be useful.
         printf(
             "plt.vlines(x%zu, [min(t,0) for t in y%zu], [max(t,0) for t in "
             "y%zu], color=colors[%zu], label=\'%s\')\n",
             i, i, i, i, series_list_[i].label.c_str());
         if (series_list_[i].point_style == PointStyle::kHighlight) {
           printf(
               "plt.plot(x%zu, y%zu, color=colors[%zu], "
               "marker='.', ls=' ')\n",
               i, i, i);
         }
       } else if (series_list_[i].line_style == LineStyle::kLine) {
         if (series_list_[i].point_style == PointStyle::kHighlight) {
           printf(
               "plt.plot(x%zu, y%zu, color=colors[%zu], label=\'%s\', "
               "marker='.')\n",
               i, i, i, series_list_[i].label.c_str());
         } else {
           printf("plt.plot(x%zu, y%zu, color=colors[%zu], label=\'%s\')\n", i,
                  i, i, series_list_[i].label.c_str());
         }
       } else if (series_list_[i].line_style == LineStyle::kStep) {
         // Draw lines from (x[0],y[0]) to (x[1],y[0]) to (x[1],y[1]) and so on
         // to illustrate the "steps". This can be expressed by duplicating all
         // elements except the first in x and the last in y.
         printf("xd%zu = [dup for v in x%zu for dup in [v, v]]\n", i, i);
         printf("yd%zu = [dup for v in y%zu for dup in [v, v]]\n", i, i);
         printf(
             "plt.plot(xd%zu[1:], yd%zu[:-1], color=colors[%zu], "
             "label=\'%s\')\n",
             i, i, i, series_list_[i].label.c_str());
         if (series_list_[i].point_style == PointStyle::kHighlight) {
           printf(
               "plt.plot(x%zu, y%zu, color=colors[%zu], "
               "marker='.', ls=' ')\n",
               i, i, i);
         }
       } else if (series_list_[i].line_style == LineStyle::kNone) {
         printf(
             "plt.plot(x%zu, y%zu, color=colors[%zu], label=\'%s\', "
             "marker='o', ls=' ')\n",
             i, i, i, series_list_[i].label.c_str());
       } else {
         printf("raise Exception(\"Unknown graph type\")\n");
       }
     }

     // IntervalSeries
     printf("interval_colors = ['#ff8e82','#5092fc','#c4ffc4','#aaaaaa']\n");
     RTC_CHECK_LE(interval_list_.size(), 4);
     // To get the intervals to show up in the legend we have to create patches
     // for them.
     printf("legend_patches = []\n");
     for (size_t i = 0; i < interval_list_.size(); i++) {
       // List intervals
       printf("\n# === IntervalSeries: %s ===\n",
              interval_list_[i].label.c_str());
       printf("ival%zu = [", i);
       if (!interval_list_[i].intervals.empty()) {
         printf("(%G, %G)", interval_list_[i].intervals[0].begin,
                interval_list_[i].intervals[0].end);
       }
       for (size_t j = 1; j < interval_list_[i].intervals.size(); j++) {
         printf(", (%G, %G)", interval_list_[i].intervals[j].begin,
                interval_list_[i].intervals[j].end);
       }
       printf("]\n");

       printf("for i in range(0, %zu):\n", interval_list_[i].intervals.size());
       if (interval_list_[i].orientation == IntervalSeries::kVertical) {
         printf(
             "  plt.axhspan(ival%zu[i][0], ival%zu[i][1], "
             "facecolor=interval_colors[%zu], "
             "alpha=0.3)\n",
             i, i, i);
       } else {
         printf(
             "  plt.axvspan(ival%zu[i][0], ival%zu[i][1], "
             "facecolor=interval_colors[%zu], "
             "alpha=0.3)\n",
             i, i, i);
       }
       printf(
           "legend_patches.append(mpatches.Patch(ec=\'black\', "
           "fc=interval_colors[%zu], label='%s'))\n",
           i, interval_list_[i].label.c_str());
     }
   }

   printf("plt.xlim(%f, %f)\n", xaxis_min_, xaxis_max_);
   printf("plt.ylim(%f, %f)\n", yaxis_min_, yaxis_max_);
   printf("plt.xlabel(\'%s\')\n", xaxis_label_.c_str());
   printf("plt.ylabel(\'%s\')\n", yaxis_label_.c_str());
   printf("plt.title(\'%s\')\n", title_.c_str());
   printf("fig = plt.gcf()\n");
   printf("fig.canvas.set_window_title(\'%s\')\n", id_.c_str());
   if (!yaxis_tick_labels_.empty()) {
     printf("yaxis_tick_labels = [");
     for (const auto& kv : yaxis_tick_labels_) {
       printf("(%f,\"%s\"),", kv.first, kv.second.c_str());
     }
     printf("]\n");
     printf("yaxis_tick_labels = list(zip(*yaxis_tick_labels))\n");
     printf("plt.yticks(*yaxis_tick_labels)\n");
   }
   if (!series_list_.empty() || !interval_list_.empty()) {
     printf("handles, labels = plt.gca().get_legend_handles_labels()\n");
     printf("for lp in legend_patches:\n");
     printf("   handles.append(lp)\n");
     printf("   labels.append(lp.get_label())\n");
     printf("plt.legend(handles, labels, loc=\'best\', fontsize=\'small\')\n");
   }
 }

 void Plot::ExportProtobuf(webrtc::analytics::Chart* chart) const {
   for (size_t i = 0; i < series_list_.size(); i++) {
     webrtc::analytics::DataSet* data_set = chart->add_data_sets();
     for (const auto& point : series_list_[i].points) {
       data_set->add_x_values(point.x);
     }
     for (const auto& point : series_list_[i].points) {
       data_set->add_y_values(point.y);
     }

     if (series_list_[i].line_style == LineStyle::kBar) {
       data_set->set_style(webrtc::analytics::ChartStyle::BAR_CHART);
     } else if (series_list_[i].line_style == LineStyle::kLine) {
       data_set->set_style(webrtc::analytics::ChartStyle::LINE_CHART);
     } else if (series_list_[i].line_style == LineStyle::kStep) {
       data_set->set_style(webrtc::analytics::ChartStyle::LINE_STEP_CHART);
     } else if (series_list_[i].line_style == LineStyle::kNone) {
       data_set->set_style(webrtc::analytics::ChartStyle::SCATTER_CHART);
     } else {
       data_set->set_style(webrtc::analytics::ChartStyle::UNDEFINED);
     }

     if (series_list_[i].point_style == PointStyle::kHighlight)
       data_set->set_highlight_points(true);

     data_set->set_label(series_list_[i].label);
   }

   chart->set_xaxis_min(xaxis_min_);
   chart->set_xaxis_max(xaxis_max_);
   chart->set_yaxis_min(yaxis_min_);
   chart->set_yaxis_max(yaxis_max_);
   chart->set_xaxis_label(xaxis_label_);
   chart->set_yaxis_label(yaxis_label_);
   chart->set_title(title_);
   chart->set_id(id_);

   for (const auto& kv : yaxis_tick_labels_) {
     webrtc::analytics::TickLabel* tick = chart->add_yaxis_tick_labels();
     tick->set_value(kv.first);
     tick->set_label(kv.second);
   }
 }

 void PlotCollection::PrintPythonCode(bool shared_xaxis) const {
   printf("import matplotlib.pyplot as plt\n");
   printf("plt.rcParams.update({'figure.max_open_warning': 0})\n");
   printf("import matplotlib.patches as mpatches\n");
   printf("import matplotlib.patheffects as pe\n");
   printf("import colorsys\n");
   for (size_t i = 0; i < plots_.size(); i++) {
     printf("plt.figure(%zu)\n", i);
     if (shared_xaxis) {
       // Link x-axes across all figures for synchronized zooming.
       if (i == 0) {
         printf("axis0 = plt.subplot(111)\n");
       } else {
         printf("plt.subplot(111, sharex=axis0)\n");
       }
     }
     plots_[i]->PrintPythonCode();
   }
   printf("plt.show()\n");
 }

 void PlotCollection::ExportProtobuf(
     webrtc::analytics::ChartCollection* collection) const {
   for (const auto& plot : plots_) {
     // TODO(terelius): Ensure that there is no way to insert plots other than
     // ProtobufPlots in a ProtobufPlotCollection. Needed to safely static_cast
     // here.
     webrtc::analytics::Chart* protobuf_representation =
         collection->add_charts();
     plot->ExportProtobuf(protobuf_representation);
   }
 }

 Plot* PlotCollection::AppendNewPlot() {
   plots_.push_back(std::make_unique<Plot>());
   return plots_.back().get();
 }

 }  // namespace webrtc
	/*
	* Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
	*
	* Use of this source code is governed by a BSD-style license
	* that can be found in the LICENSE file in the root of the source
	* tree. An additional intellectual property rights grant can be found
	* in the file PATENTS. All contributing project authors may
	* be found in the AUTHORS file in the root of the source tree.
	*/

	#include "rtc_tools/rtc_event_log_visualizer/plot_base.h"

	#include <algorithm>
	#include <memory>

	#include "rtc_base/checks.h"

	namespace webrtc {

	void Plot::SetXAxis(float min_value,
	float max_value,
	std::string label,
	float left_margin,
	float right_margin) {
	RTC_DCHECK_LE(min_value, max_value);
	xaxis_min_ = min_value - left_margin * (max_value - min_value);
	xaxis_max_ = max_value + right_margin * (max_value - min_value);
	xaxis_label_ = label;
	}

	void Plot::SetSuggestedXAxis(float min_value,
	float max_value,
	std::string label,
	float left_margin,
	float right_margin) {
	for (const auto& series : series_list_) {
	for (const auto& point : series.points) {
	min_value = std::min(min_value, point.x);
	max_value = std::max(max_value, point.x);
	}
	}
	SetXAxis(min_value, max_value, label, left_margin, right_margin);
	}

	void Plot::SetYAxis(float min_value,
	float max_value,
	std::string label,
	float bottom_margin,
	float top_margin) {
	RTC_DCHECK_LE(min_value, max_value);
	yaxis_min_ = min_value - bottom_margin * (max_value - min_value);
	yaxis_max_ = max_value + top_margin * (max_value - min_value);
	yaxis_label_ = label;
	}

	void Plot::SetSuggestedYAxis(float min_value,
	float max_value,
	std::string label,
	float bottom_margin,
	float top_margin) {
	for (const auto& series : series_list_) {
	for (const auto& point : series.points) {
	min_value = std::min(min_value, point.y);
	max_value = std::max(max_value, point.y);
	}
	}
	SetYAxis(min_value, max_value, label, bottom_margin, top_margin);
	}

	void Plot::SetYAxisTickLabels(
	const std::vector<std::pair<float, std::string>>& labels) {
	yaxis_tick_labels_ = labels;
	}

	void Plot::SetTitle(const std::string& title) {
	title_ = title;
	}

	void Plot::SetId(const std::string& id) {
	id_ = id;
	}

	void Plot::AppendTimeSeries(TimeSeries&& time_series) {
	series_list_.emplace_back(std::move(time_series));
	}

	void Plot::AppendIntervalSeries(IntervalSeries&& interval_series) {
	interval_list_.emplace_back(std::move(interval_series));
	}

	void Plot::AppendTimeSeriesIfNotEmpty(TimeSeries&& time_series) {
	if (!time_series.points.empty()) {
	series_list_.emplace_back(std::move(time_series));
	}
	}

	void Plot::PrintPythonCode() const {
	// Write python commands to stdout. Intended program usage is
	// ./event_log_visualizer event_log160330.dump \| python

	if (!series_list_.empty()) {
	printf("color_count = %zu\n", series_list_.size());
	printf(
	"hls_colors = [(i1.0/color_count, 0.25+i0.5/color_count, 0.8) for i "
	"in range(color_count)]\n");
	printf("colors = [colorsys.hls_to_rgb(*hls) for hls in hls_colors]\n");

	for (size_t i = 0; i < series_list_.size(); i++) {
	printf("\n# === Series: %s ===\n", series_list_[i].label.c_str());
	// List x coordinates
	printf("x%zu = [", i);
	if (!series_list_[i].points.empty())
	printf("%.3f", series_list_[i].points[0].x);
	for (size_t j = 1; j < series_list_[i].points.size(); j++)
	printf(", %.3f", series_list_[i].points[j].x);
	printf("]\n");

	// List y coordinates
	printf("y%zu = [", i);
	if (!series_list_[i].points.empty())
	printf("%G", series_list_[i].points[0].y);
	for (size_t j = 1; j < series_list_[i].points.size(); j++)
	printf(", %G", series_list_[i].points[j].y);
	printf("]\n");

	if (series_list_[i].line_style == LineStyle::kBar) {
	// There is a plt.bar function that draws bar plots,
	// but it is way too slow to be useful.
	printf(
	"plt.vlines(x%zu, [min(t,0) for t in y%zu], [max(t,0) for t in "
	"y%zu], color=colors[%zu], label=\'%s\')\n",
	i, i, i, i, series_list_[i].label.c_str());
	if (series_list_[i].point_style == PointStyle::kHighlight) {
	printf(
	"plt.plot(x%zu, y%zu, color=colors[%zu], "
	"marker='.', ls=' ')\n",
	i, i, i);
	}
	} else if (series_list_[i].line_style == LineStyle::kLine) {
	if (series_list_[i].point_style == PointStyle::kHighlight) {
	printf(
	"plt.plot(x%zu, y%zu, color=colors[%zu], label=\'%s\', "
	"marker='.')\n",
	i, i, i, series_list_[i].label.c_str());
	} else {
	printf("plt.plot(x%zu, y%zu, color=colors[%zu], label=\'%s\')\n", i,
	i, i, series_list_[i].label.c_str());
	}
	} else if (series_list_[i].line_style == LineStyle::kStep) {
	// Draw lines from (x[0],y[0]) to (x[1],y[0]) to (x[1],y[1]) and so on
	// to illustrate the "steps". This can be expressed by duplicating all
	// elements except the first in x and the last in y.
	printf("xd%zu = [dup for v in x%zu for dup in [v, v]]\n", i, i);
	printf("yd%zu = [dup for v in y%zu for dup in [v, v]]\n", i, i);
	printf(
	"plt.plot(xd%zu[1:], yd%zu[:-1], color=colors[%zu], "
	"label=\'%s\')\n",
	i, i, i, series_list_[i].label.c_str());
	if (series_list_[i].point_style == PointStyle::kHighlight) {
	printf(
	"plt.plot(x%zu, y%zu, color=colors[%zu], "
	"marker='.', ls=' ')\n",
	i, i, i);
	}
	} else if (series_list_[i].line_style == LineStyle::kNone) {
	printf(
	"plt.plot(x%zu, y%zu, color=colors[%zu], label=\'%s\', "
	"marker='o', ls=' ')\n",
	i, i, i, series_list_[i].label.c_str());
	} else {
	printf("raise Exception(\"Unknown graph type\")\n");
	}
	}

	// IntervalSeries
	printf("interval_colors = ['#ff8e82','#5092fc','#c4ffc4','#aaaaaa']\n");
	RTC_CHECK_LE(interval_list_.size(), 4);
	// To get the intervals to show up in the legend we have to create patches
	// for them.
	printf("legend_patches = []\n");
	for (size_t i = 0; i < interval_list_.size(); i++) {
	// List intervals
	printf("\n# === IntervalSeries: %s ===\n",
	interval_list_[i].label.c_str());
	printf("ival%zu = [", i);
	if (!interval_list_[i].intervals.empty()) {
	printf("(%G, %G)", interval_list_[i].intervals[0].begin,
	interval_list_[i].intervals[0].end);
	}
	for (size_t j = 1; j < interval_list_[i].intervals.size(); j++) {
	printf(", (%G, %G)", interval_list_[i].intervals[j].begin,
	interval_list_[i].intervals[j].end);
	}
	printf("]\n");

	printf("for i in range(0, %zu):\n", interval_list_[i].intervals.size());
	if (interval_list_[i].orientation == IntervalSeries::kVertical) {
	printf(
	" plt.axhspan(ival%zu[i][0], ival%zu[i][1], "
	"facecolor=interval_colors[%zu], "
	"alpha=0.3)\n",
	i, i, i);
	} else {
	printf(
	" plt.axvspan(ival%zu[i][0], ival%zu[i][1], "
	"facecolor=interval_colors[%zu], "
	"alpha=0.3)\n",
	i, i, i);
	}
	printf(
	"legend_patches.append(mpatches.Patch(ec=\'black\', "
	"fc=interval_colors[%zu], label='%s'))\n",
	i, interval_list_[i].label.c_str());
	}
	}

	printf("plt.xlim(%f, %f)\n", xaxis_min_, xaxis_max_);
	printf("plt.ylim(%f, %f)\n", yaxis_min_, yaxis_max_);
	printf("plt.xlabel(\'%s\')\n", xaxis_label_.c_str());
	printf("plt.ylabel(\'%s\')\n", yaxis_label_.c_str());
	printf("plt.title(\'%s\')\n", title_.c_str());
	printf("fig = plt.gcf()\n");
	printf("fig.canvas.set_window_title(\'%s\')\n", id_.c_str());
	if (!yaxis_tick_labels_.empty()) {
	printf("yaxis_tick_labels = [");
	for (const auto& kv : yaxis_tick_labels_) {
	printf("(%f,\"%s\"),", kv.first, kv.second.c_str());
	}
	printf("]\n");
	printf("yaxis_tick_labels = list(zip(*yaxis_tick_labels))\n");
	printf("plt.yticks(*yaxis_tick_labels)\n");
	}
	if (!series_list_.empty() \|\| !interval_list_.empty()) {
	printf("handles, labels = plt.gca().get_legend_handles_labels()\n");
	printf("for lp in legend_patches:\n");
	printf(" handles.append(lp)\n");
	printf(" labels.append(lp.get_label())\n");
	printf("plt.legend(handles, labels, loc=\'best\', fontsize=\'small\')\n");
	}
	}

	void Plot::ExportProtobuf(webrtc::analytics::Chart* chart) const {
	for (size_t i = 0; i < series_list_.size(); i++) {
	webrtc::analytics::DataSet* data_set = chart->add_data_sets();
	for (const auto& point : series_list_[i].points) {
	data_set->add_x_values(point.x);
	}
	for (const auto& point : series_list_[i].points) {
	data_set->add_y_values(point.y);
	}

	if (series_list_[i].line_style == LineStyle::kBar) {
	data_set->set_style(webrtc::analytics::ChartStyle::BAR_CHART);
	} else if (series_list_[i].line_style == LineStyle::kLine) {
	data_set->set_style(webrtc::analytics::ChartStyle::LINE_CHART);
	} else if (series_list_[i].line_style == LineStyle::kStep) {
	data_set->set_style(webrtc::analytics::ChartStyle::LINE_STEP_CHART);
	} else if (series_list_[i].line_style == LineStyle::kNone) {
	data_set->set_style(webrtc::analytics::ChartStyle::SCATTER_CHART);
	} else {
	data_set->set_style(webrtc::analytics::ChartStyle::UNDEFINED);
	}

	if (series_list_[i].point_style == PointStyle::kHighlight)
	data_set->set_highlight_points(true);

	data_set->set_label(series_list_[i].label);
	}

	chart->set_xaxis_min(xaxis_min_);
	chart->set_xaxis_max(xaxis_max_);
	chart->set_yaxis_min(yaxis_min_);
	chart->set_yaxis_max(yaxis_max_);
	chart->set_xaxis_label(xaxis_label_);
	chart->set_yaxis_label(yaxis_label_);
	chart->set_title(title_);
	chart->set_id(id_);

	for (const auto& kv : yaxis_tick_labels_) {
	webrtc::analytics::TickLabel* tick = chart->add_yaxis_tick_labels();
	tick->set_value(kv.first);
	tick->set_label(kv.second);
	}
	}

	void PlotCollection::PrintPythonCode(bool shared_xaxis) const {
	printf("import matplotlib.pyplot as plt\n");
	printf("plt.rcParams.update({'figure.max_open_warning': 0})\n");
	printf("import matplotlib.patches as mpatches\n");
	printf("import matplotlib.patheffects as pe\n");
	printf("import colorsys\n");
	for (size_t i = 0; i < plots_.size(); i++) {
	printf("plt.figure(%zu)\n", i);
	if (shared_xaxis) {
	// Link x-axes across all figures for synchronized zooming.
	if (i == 0) {
	printf("axis0 = plt.subplot(111)\n");
	} else {
	printf("plt.subplot(111, sharex=axis0)\n");
	}
	}
	plots_[i]->PrintPythonCode();
	}
	printf("plt.show()\n");
	}

	void PlotCollection::ExportProtobuf(
	webrtc::analytics::ChartCollection* collection) const {
	for (const auto& plot : plots_) {
	// TODO(terelius): Ensure that there is no way to insert plots other than
	// ProtobufPlots in a ProtobufPlotCollection. Needed to safely static_cast
	// here.
	webrtc::analytics::Chart* protobuf_representation =
	collection->add_charts();
	plot->ExportProtobuf(protobuf_representation);
	}
	}

	Plot* PlotCollection::AppendNewPlot() {
	plots_.push_back(std::make_unique<Plot>());
	return plots_.back().get();
	}

	} // namespace webrtc