A simple timer for C++ based programs

Timer.cpp

//
// Created by Jip J. Dekker on 05/10/15.
//

#include "Timer.h"

void Timer::start() {
    if (output) cout << "\t Start Application"<< endl;
    app.start = high_resolution_clock::now();
}

void Timer::start(string event) {
    if (output) cout << "\t\t Start: " << event << endl;
    TimeEvent* t = &timers[event];
    t->start = high_resolution_clock::now();
}

void Timer::stop() {
    app.stop = high_resolution_clock::now();
    app.time_span[0] = duration_cast<duration<double, milli>>(app.stop - app.start);
    app.runs = 1;

    if (output) cout << "\t Stop Application"<< endl;
}

void Timer::stop(string event, int run) {
    TimeEvent* t = &timers[event];
    t->stop = high_resolution_clock::now();
    t->time_span[run] = duration_cast<duration<double, milli>>(t->stop - t->start);
    t->runs = t->runs < run ? run : t->runs;

    if (output) cout << "\t\t Stop: " << event << endl;
}

void Timer::dump(ostream& s, bool group_runs) {
    s.width(10);
    s << "-++== " << title << " ==++-" << endl;
    if (group_runs) {
        dump_runs(s);
    } else {
        dump_events(s);
    }
}

void Timer::dump_runs(ostream& s) {
    int max_runs = 0; // We assume at least one run.
    for (int i = 0; i <= max_runs; ++i) {
        s << endl;
        s.width(20);
        s << "=== Run " << i << ": ===" << endl;
        for (auto &t : timers) {
            s.width(30);
            max_runs = max_runs < t.second.runs ? t.second.runs : max_runs;
            if(t.second.time_span.find(i) != t.second.time_span.end()) {
                s << left << t.first + ":";
                s << right << t.second.time_span[i].count() << " ms" << endl;
            }
        }
    }

    s << endl;
    s.width(30);
    s << "=== Total Times: ===" << endl;
    for (auto &t : timers) {
        duration<double, milli> total = high_resolution_clock::duration::zero();
        for (auto &time : t.second.time_span) {
            total += time.second;
        }
        s.width(30);
        s << left << t.first + ":";
        s << total.count() << " ms" << endl;
    }

    s << endl;
    s.width(30);
    s << internal << "=== Average Times: ===" << endl;
    for (auto &t : timers) {
        duration<double, milli> total = high_resolution_clock::duration::zero();
        for (auto &time : t.second.time_span) {
            total += time.second;
        }
        s.width(30);
        s << left << t.first + ":";
        s << right << total.count()/t.second.time_span.size() << " ms" << endl;
    }

    s << endl << endl;
    s.width(30);
    s << left<< "Total runtime:";
    s << right << app.time_span[0].count() << " ms" << endl;
}

void Timer::dump_events(ostream& s) {
    for (auto &t : timers) {
        s << endl;
        s.width(10);
        s << "=== " << t.first << ": ===" << endl;
        duration<double, milli> total = high_resolution_clock::duration::zero();
        for (auto &time : t.second.time_span) {
            s.width(20);
            s << left << "Run " + to_string(time.first) + ":";
            s << right << time.second.count() << " ms" << endl;
            total += time.second;
        }
        s.width(20);
        s << left<< "Total:";
        s << right << total.count() << " ms" << endl;
        s.width(20);
        s << left << "Average:";
        s << right << total.count()/t.second.time_span.size() << " ms" << endl;
    }

    s << endl << endl;
    s.width(20);
    s << left<< "Total runtime:";
    s << right << app.time_span[0].count() << " ms" << endl;
}

Timer.h

//
// Created by Jip J. Dekker on 05/10/15.
//

#ifndef PROJECT_TIMER_H
#define PROJECT_TIMER_H

#include <chrono>
#include <string>
#include <map>
#include <vector>
#include <iostream>

using namespace std;
using namespace std::chrono;

class Timer {
public:
    Timer(string title, bool output = false){this->output = output; this->title = title;};
    virtual ~Timer(){};
    // Start Application
    virtual void start();
    // Start the timer for (new) event with name |event|
    virtual void start(string event);
    // Stop Application
    virtual void stop();
    // Stop the timer for event with name |event| and save time with run number
    virtual void stop(string event, int run);
    // Output all timed events to the ostream.
    virtual void dump(ostream& s, bool group_runs = false);
protected:
    class TimeEvent {
    public:
        TimeEvent(){runs = 0;}
        high_resolution_clock::time_point start, stop;
        map<int, duration<double, milli>> time_span;
        int runs;
    };
    map<string, TimeEvent> timers;
    TimeEvent app;
    bool output;
    string title;
private:
    void dump_runs(ostream& s);
    void dump_events(ostream& s);
};

#endif //PROJECT_TIMER_H