series排序取前十

您可以使用Python中的pandas库来对系列进行排序并提取前十个元素。首先，确保您已经安装了pandas库，然后按照以下步骤操作：

1. 导入pandas库：

import pandas as pd

2. 创建一个Series对象：

series = pd.Series([5, 10, 15, 20, 25, 30, 35, 40, 45, 50])

3. 对Series进行排序：

sorted_series = series.sort_values(ascending=False)

4. 提取排序后的前十个元素：

top_ten = sorted_series.head(10)

现在，变量`top_ten`将包含排序后的前十个元素。您可以打印或进一步处理这个变量来满足您的需求。

相关问题

series取最后一条记录

假设你的数据已经按照某个字段排序，可以使用以下 SQL 语句来取最后一条记录：

SELECT * FROM your_table ORDER BY your_field DESC LIMIT 1;

其中 `your_table` 是你要查询的表名，`your_field` 是你要排序的字段名。`DESC` 表示降序排序，也就是从大到小排序，这样最后一条记录就是最小的。`LIMIT 1` 表示只取一条记录。

如果你不确定数据是否已经排序，或者想要按照自己的规则排序，可以先将所有记录按照自己的规则排序，然后再取最后一条记录。例如，按照 ID 字段排序：

SELECT * FROM your_table ORDER BY id DESC LIMIT 1;

这样就可以取到 ID 最大的记录，也就是最后一条记录。

用C++实现16、运动会计分系统 [问题描述] 假设参加运动会有 n 个系，系编号为 1 n。比赛分成 m个男子项目，和 w 个女子项目。项目编号为男子 1……m，女子 m+1……m+w。不同的项目取前 五名或前三名积分；取前五名的积分分别为：7、5、3、2、1，前三名的积分分 别为：5、3、2；哪些取前五名或前三名由学生自己设定。（m<=10,n<=15） [基本要求] 系统功能要求： （1）可以输入各个项目的前三名或前五名的成绩； （2）能统计各系总分； （3）可以按系编号、系总分、男女团体总分排序输出； （4）可以按系编号查询学校某个项目的情况；可以按项目编号查询取得前 三或前五名的系。 [实现提示] （1）输入数据形式和范围：系或运行项目可以用 20 以内的整数表示；也可 以直接输入系的名称或运动项目的名称； （2）界面要求：有合理的提示，每个功能可以设立菜单，根据提示，可以 完成相关的功能要求

以下是一个 C++ 实现的运动会计分系统的代码，实现了上述基本要求：

#include <iostream>
#include <map>
#include <vector>
#include <algorithm>
using namespace std;

const int MAX_M = 10, MAX_N = 15;

struct Score {
    string name;
    int points;
    Score(string n = "", int p = 0) : name(n), points(p) {}
    bool operator<(const Score& other) const {
        return points > other.points;
    }
};

struct Event {
    string name;
    int type; // 0: male, 1: female
    int top; // top 3 or top 5
    map<int, vector<Score>> scores; // key: series number, value: scores
    Event(string n = "", int t = 0, int tp = 5) : name(n), type(t), top(tp) {}
};

struct Series {
    string name;
    int points;
    map<int, Event> events; // key: event number, value: event
    Series(string n = "") : name(n), points(0) {}
};

struct School {
    string name;
    int points;
    map<int, Series> series; // key: series number, value: series
    School(string n = "") : name(n), points(0) {}
};

void print_menu() {
    cout << "1. Input scores\n";
    cout << "2. Calculate scores\n";
    cout << "3. Sort and output\n";
    cout << "4. Query by series\n";
    cout << "5. Query by event\n";
    cout << "6. Quit\n";
}

void input_scores(map<int, Event>& events, int top) {
    cout << "Input scores:\n";
    for (auto& kv : events) {
        auto& event = kv.second;
        cout << "Event " << event.name << ":\n";
        for (int i = 1; i <= MAX_N; i++) {
            cout << "Series " << i << ":\n";
            for (int j = 1; j <= top; j++) {
                string name;
                int score;
                cout << "Score " << j << ": ";
                cin >> name >> score;
                event.scores[i].push_back({name, score});
            }
        }
    }
}

void calculate_scores(map<int, Series>& series, int top) {
    for (auto& kv : series) {
        auto& s = kv.second;
        s.points = 0;
        for (auto& kv2 : s.events) {
            auto& e = kv2.second;
            for (auto& kv3 : e.scores) {
                auto& scores = kv3.second;
                int n = min((int)scores.size(), top);
                for (int i = 0; i < n; i++) {
                    int points = (top == 5) ? (i < 3 ? (i == 0 ? 5 : (i == 1 ? 3 : 2)) : (i == 3 ? 1 : 0))
                                             : (i == 0 ? 5 : (i == 1 ? 3 : 2));
                    s.points += points;
                    e.points += points;
                    scores[i].points = points;
                }
            }
        }
    }
}

void sort_and_output(const map<int, School>& schools) {
    vector<pair<int, School>> sorted_schools(schools.begin(), schools.end());
    sort(sorted_schools.begin(), sorted_schools.end(), [](auto& a, auto& b) {
        return a.second.points > b.second.points || (a.second.points == b.second.points && a.second.name < b.second.name);
    });
    cout << "School scores:\n";
    for (auto& kv : sorted_schools) {
        auto& s = kv.second;
        cout << s.name << ": " << s.points << "\n";
        vector<pair<int, Series>> sorted_series(s.series.begin(), s.series.end());
        sort(sorted_series.begin(), sorted_series.end(), [](auto& a, auto& b) {
            return a.second.points > b.second.points || (a.second.points == b.second.points && a.second.name < b.second.name);
        });
        for (auto& kv2 : sorted_series) {
            auto& ser = kv2.second;
            cout << "\t" << ser.name << ": " << ser.points << "\n";
            vector<pair<int, Event>> sorted_events(ser.events.begin(), ser.events.end());
            sort(sorted_events.begin(), sorted_events.end(), [](auto& a, auto& b) {
                return a.second.points > b.second.points || (a.second.points == b.second.points && a.second.name < b.second.name);
            });
            for (auto& kv3 : sorted_events) {
                auto& e = kv3.second;
                cout << "\t\t" << e.name << ": " << e.points << "\n";
                for (auto& kv4 : e.scores) {
                    auto& scores = kv4.second;
                    sort(scores.begin(), scores.end());
                    cout << "\t\t\tSeries " << kv4.first << ":\n";
                    for (auto& score : scores) {
                        cout << "\t\t\t\t" << score.name << ": " << score.points << "\n";
                    }
                }
            }
        }
    }
}

void query_by_series(const map<int, School>& schools) {
    int sn;
    cout << "Input series number: ";
    cin >> sn;
    for (auto& kv : schools) {
        auto& s = kv.second;
        for (auto& kv2 : s.series) {
            auto& ser = kv2.second;
            if (kv2.first == sn) {
                cout << "Series " << ser.name << ":\n";
                vector<pair<int, Event>> sorted_events(ser.events.begin(), ser.events.end());
                sort(sorted_events.begin(), sorted_events.end(), [](auto& a, auto& b) {
                    return a.second.points > b.second.points || (a.second.points == b.second.points && a.second.name < b.second.name);
                });
                for (auto& kv3 : sorted_events) {
                    auto& e = kv3.second;
                    cout << "\t" << e.name << ":\n";
                    for (auto& kv4 : e.scores) {
                        auto& scores = kv4.second;
                        sort(scores.begin(), scores.end());
                        cout << "\t\tSeries " << kv4.first << ":\n";
                        for (auto& score : scores) {
                            if (score.points > 0) {
                                cout << "\t\t\t" << s.name << ": " << score.points << "\n";
                            }
                        }
                    }
                }
            }
        }
    }
}

void query_by_event(const map<int, School>& schools) {
    int en, top;
    cout << "Input event number: ";
    cin >> en;
    cout << "Input top: ";
    cin >> top;
    for (auto& kv : schools) {
        auto& s = kv.second;
        for (auto& kv2 : s.series) {
            auto& ser = kv2.second;
            for (auto& kv3 : ser.events) {
                auto& e = kv3.second;
                if (kv3.first == en) {
                    cout << "Event " << e.name << ":\n";
                    vector<pair<int, Score>> sorted_scores;
                    for (auto& kv4 : e.scores) {
                        auto& scores = kv4.second;
                        for (auto& score : scores) {
                            if (score.points > 0) {
                                sorted_scores.emplace_back(kv4.first, score);
                            }
                        }
                    }
                    sort(sorted_scores.begin(), sorted_scores.end(), [](auto& a, auto& b) {
                        return a.second.points > b.second.points || (a.second.points == b.second.points && a.second.name < b.second.name);
                    });
                    for (auto& p : sorted_scores) {
                        if (p.second.points > 0 && (top == -1 || p.second.points <= top)) {
                            cout << "\t" << s.name << " Series " << p.first << " " << p.second.name << ": " << p.second.points << "\n";
                        }
                    }
                }
            }
        }
    }
}

int main() {
    int n, m, w;
    cout << "Input number of series: ";
    cin >> n;
    map<int, School> schools;
    for (int i = 1; i <= n; i++) {
        string name;
        cout << "Input name of series " << i << ": ";
        cin >> name;
        schools.emplace(i, School(name));
        auto& series = schools[i].series;
        int k;
        cout << "Input number of events: ";
        cin >> k;
        for (int j = 1; j <= k; j++) {
            string ename;
            int type, top;
            cout << "Input name of event " << j << ": ";
            cin >> ename;
            cout << "Input type (0 for male, 1 for female): ";
            cin >> type;
            cout << "Input top (3 or 5): ";
            cin >> top;
            series.emplace(j, Series(ename));
            series[j].events.emplace(1, Event(ename, type, top));
        }
    }

    while (true) {
        print_menu();
        int choice;
        cin >> choice;
        if (choice == 1) {
            input_scores(schools[1].series[1].events, schools[1].series[1].events[1].top);
        } else if (choice == 2) {
            calculate_scores(schools[1].series, schools[1].series[1].events[1].top);
        } else if (choice == 3) {
            sort_and_output(schools);
        } else if (choice == 4) {
            query_by_series(schools);
        } else if (choice == 5) {
            query_by_event(schools);
        } else if (choice == 6) {
            break;
        } else {
            cout << "Invalid choice\n";
        }
    }

    return 0;
}

运行时会提示输入系和项目的信息，然后进入主界面，输入数字选择对应的功能。可以不按顺序执行，每次执行前需要先输入数据或计算分数。其中第4、5个功能需要输入查询条件。