sspai-100-hours-series-python/code/newsletter/N6/method_chaining.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "source": [
    "# 链式调用示例"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%% md\n"
    }
   },
   "outputs": []
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "outputs": [
    {
     "data": {
      "text/plain": "        date\n0 2022-01-02\n1 2022-01-09\n2 2022-01-16\n3 2022-01-23\n4 2022-01-30",
      "text/html": "<div>\n<style scoped>\n    .dataframe tbody tr th:only-of-type {\n        vertical-align: middle;\n    }\n\n    .dataframe tbody tr th {\n        vertical-align: top;\n    }\n\n    .dataframe thead th {\n        text-align: right;\n    }\n</style>\n<table border=\"1\" class=\"dataframe\">\n  <thead>\n    <tr style=\"text-align: right;\">\n      <th></th>\n      <th>date</th>\n    </tr>\n  </thead>\n  <tbody>\n    <tr>\n      <th>0</th>\n      <td>2022-01-02</td>\n    </tr>\n    <tr>\n      <th>1</th>\n      <td>2022-01-09</td>\n    </tr>\n    <tr>\n      <th>2</th>\n      <td>2022-01-16</td>\n    </tr>\n    <tr>\n      <th>3</th>\n      <td>2022-01-23</td>\n    </tr>\n    <tr>\n      <th>4</th>\n      <td>2022-01-30</td>\n    </tr>\n  </tbody>\n</table>\n</div>"
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "data = pd.DataFrame(dict(date=pd.date_range(\"20220101\", \"20220201\", freq=\"1W\")))\n",
    "data.head()"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "outputs": [
    {
     "data": {
      "text/plain": "         date  year month day year_month\n0  2022-01-02  2022    01  02     202201\n1  2022-01-09  2022    01  09     202201\n2  2022-01-16  2022    01  16     202201\n3  2022-01-23  2022    01  23     202201\n4  2022-01-30  2022    01  30     202201",
      "text/html": "<div>\n<style scoped>\n    .dataframe tbody tr th:only-of-type {\n        vertical-align: middle;\n    }\n\n    .dataframe tbody tr th {\n        vertical-align: top;\n    }\n\n    .dataframe thead th {\n        text-align: right;\n    }\n</style>\n<table border=\"1\" class=\"dataframe\">\n  <thead>\n    <tr style=\"text-align: right;\">\n      <th></th>\n      <th>date</th>\n      <th>year</th>\n      <th>month</th>\n      <th>day</th>\n      <th>year_month</th>\n    </tr>\n  </thead>\n  <tbody>\n    <tr>\n      <th>0</th>\n      <td>2022-01-02</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>02</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>1</th>\n      <td>2022-01-09</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>09</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>2</th>\n      <td>2022-01-16</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>16</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>3</th>\n      <td>2022-01-23</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>23</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>4</th>\n      <td>2022-01-30</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>30</td>\n      <td>202201</td>\n    </tr>\n  </tbody>\n</table>\n</div>"
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data[\"date\"] = data[\"date\"].astype(str)\n",
    "data[\"year\"] = data[\"date\"].map(lambda s: s.split(\"-\")[0])\n",
    "data[\"month\"] = data[\"date\"].map(lambda s: s.split(\"-\")[1])\n",
    "data[\"day\"] = data[\"date\"].map(lambda s: s.split(\"-\")[2])\n",
    "data[\"year_month\"] = data[\"year\"].str.cat(data[\"month\"])\n",
    "data.head()"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "markdown",
   "source": [
    "## 第一种重构方式"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%% md\n"
    }
   }
  },
  {
   "cell_type": "code",
   "source": [
    "data = (\n",
    "    pd.DataFrame({\"date\": pd.date_range(\"20220101\", \"20220201\", freq=\"1W\")})\n",
    "    .astype({\"date\": \"str\"})[\"date\"]\n",
    "    .str.split(\"-\", expand=True)\n",
    "    .rename(\n",
    "        columns={\n",
    "            0: \"year\",\n",
    "            1: \"month\",\n",
    "            2: \"day\",\n",
    "        }\n",
    "    )\n",
    "    .assign(\n",
    "        date=lambda df: df.apply(lambda r: \"-\".join(r.tolist()), axis=1),\n",
    "        year_month=lambda df: df[\"year\"].str.cat(df[\"month\"]),\n",
    "    )\n",
    ")\n",
    "data.head()"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   },
   "execution_count": 4,
   "outputs": [
    {
     "data": {
      "text/plain": "   year month day        date year_month\n0  2022    01  02  2022-01-02     202201\n1  2022    01  09  2022-01-09     202201\n2  2022    01  16  2022-01-16     202201\n3  2022    01  23  2022-01-23     202201\n4  2022    01  30  2022-01-30     202201",
      "text/html": "<div>\n<style scoped>\n    .dataframe tbody tr th:only-of-type {\n        vertical-align: middle;\n    }\n\n    .dataframe tbody tr th {\n        vertical-align: top;\n    }\n\n    .dataframe thead th {\n        text-align: right;\n    }\n</style>\n<table border=\"1\" class=\"dataframe\">\n  <thead>\n    <tr style=\"text-align: right;\">\n      <th></th>\n      <th>year</th>\n      <th>month</th>\n      <th>day</th>\n      <th>date</th>\n      <th>year_month</th>\n    </tr>\n  </thead>\n  <tbody>\n    <tr>\n      <th>0</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>02</td>\n      <td>2022-01-02</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>1</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>09</td>\n      <td>2022-01-09</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>2</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>16</td>\n      <td>2022-01-16</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>3</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>23</td>\n      <td>2022-01-23</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>4</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>30</td>\n      <td>2022-01-30</td>\n      <td>202201</td>\n    </tr>\n  </tbody>\n</table>\n</div>"
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ]
  },
  {
   "cell_type": "markdown",
   "source": [
    "## 第二种重构方式"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%% md\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "outputs": [
    {
     "data": {
      "text/plain": "   year month day        date year_month\n0  2022    01  02  2022-01-02     202201\n1  2022    01  09  2022-01-09     202201\n2  2022    01  16  2022-01-16     202201\n3  2022    01  23  2022-01-23     202201\n4  2022    01  30  2022-01-30     202201",
      "text/html": "<div>\n<style scoped>\n    .dataframe tbody tr th:only-of-type {\n        vertical-align: middle;\n    }\n\n    .dataframe tbody tr th {\n        vertical-align: top;\n    }\n\n    .dataframe thead th {\n        text-align: right;\n    }\n</style>\n<table border=\"1\" class=\"dataframe\">\n  <thead>\n    <tr style=\"text-align: right;\">\n      <th></th>\n      <th>year</th>\n      <th>month</th>\n      <th>day</th>\n      <th>date</th>\n      <th>year_month</th>\n    </tr>\n  </thead>\n  <tbody>\n    <tr>\n      <th>0</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>02</td>\n      <td>2022-01-02</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>1</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>09</td>\n      <td>2022-01-09</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>2</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>16</td>\n      <td>2022-01-16</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>3</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>23</td>\n      <td>2022-01-23</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>4</th>\n      <td>2022</td>\n      <td>01</td>\n      <td>30</td>\n      <td>2022-01-30</td>\n      <td>202201</td>\n    </tr>\n  </tbody>\n</table>\n</div>"
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data = (\n",
    "    pd.DataFrame({\"date\": pd.date_range(\"20220101\", \"20220201\", freq=\"1W\")})\n",
    "    .astype({\"date\": \"str\"})[\"date\"]\n",
    "    .str.extract(r\"(?P<year>\\d{4})-(?P<month>\\d{2})-(?P<day>\\d{2})\")\n",
    "    .assign(\n",
    "        date=lambda df: df.apply(lambda row: \"-\".join(row.tolist()), axis=1),\n",
    "        year_month=lambda df: df[\"year\"].str.cat(df[\"month\"]),\n",
    "    )\n",
    ")\n",
    "\n",
    "data.head()"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "markdown",
   "source": [
    "## 第三种重构方式"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%% md\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "outputs": [
    {
     "data": {
      "text/plain": "         date  year month day year_month\n0  2022-01-02  2022    01  02     202201\n1  2022-01-09  2022    01  09     202201\n2  2022-01-16  2022    01  16     202201\n3  2022-01-23  2022    01  23     202201\n4  2022-01-30  2022    01  30     202201",
      "text/html": "<div>\n<style scoped>\n    .dataframe tbody tr th:only-of-type {\n        vertical-align: middle;\n    }\n\n    .dataframe tbody tr th {\n        vertical-align: top;\n    }\n\n    .dataframe thead th {\n        text-align: right;\n    }\n</style>\n<table border=\"1\" class=\"dataframe\">\n  <thead>\n    <tr style=\"text-align: right;\">\n      <th></th>\n      <th>date</th>\n      <th>year</th>\n      <th>month</th>\n      <th>day</th>\n      <th>year_month</th>\n    </tr>\n  </thead>\n  <tbody>\n    <tr>\n      <th>0</th>\n      <td>2022-01-02</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>02</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>1</th>\n      <td>2022-01-09</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>09</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>2</th>\n      <td>2022-01-16</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>16</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>3</th>\n      <td>2022-01-23</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>23</td>\n      <td>202201</td>\n    </tr>\n    <tr>\n      <th>4</th>\n      <td>2022-01-30</td>\n      <td>2022</td>\n      <td>01</td>\n      <td>30</td>\n      <td>202201</td>\n    </tr>\n  </tbody>\n</table>\n</div>"
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data = (\n",
    "    pd.DataFrame({\"date\": pd.date_range(\"20220101\", \"20220201\", freq=\"1W\")})\n",
    "    .assign(\n",
    "        year=lambda df: df[\"date\"].dt.year,\n",
    "        month=lambda df: df[\"date\"].dt.month.astype(str).str.zfill(2),\n",
    "        day=lambda df: df[\"date\"].dt.day.astype(str).str.zfill(2),\n",
    "        year_month=lambda df: df[\"date\"].dt.strftime(\"%Y%m\"),\n",
    "    )\n",
    "    .astype(str)\n",
    ")\n",
    "data.head()"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "markdown",
   "source": [
    "# 链式调用的实现原理以及优劣"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%% md\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "outputs": [],
   "source": [
    "class Command:\n",
    "    def __init__(self, name=None):\n",
    "        self.name = name\n",
    "\n",
    "    def set_options(self, **kwargs):\n",
    "        for k, v in kwargs.items():\n",
    "            if not hasattr(self, k):\n",
    "                setattr(self, k, v)\n",
    "        return self\n",
    "\n",
    "    def parse(self):\n",
    "        opts = [f\"{v}\" for k, v in self.__dict__.items() if k != \"name\"]\n",
    "        final = \" \".join([self.name, *opts])\n",
    "        return final\n",
    "\n",
    "    def __repr__(self):\n",
    "        opts = [f\"{k}={v}\" for k, v in self.__dict__.items() if k != \"name\"]\n",
    "        return f\"Command<name: {self.name}, options[{', '.join(opts)}]>\""
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "outputs": [],
   "source": [
    "cmd = Command(\"curl\").set_options(verbose=\"-v\").set_options(target=\"sspai.com\")"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Command<name: curl, options[verbose=-v, target=sspai.com]>\n"
     ]
    }
   ],
   "source": [
    "print(cmd)"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "curl -v sspai.com\n"
     ]
    }
   ],
   "source": [
    "print(cmd.parse())"
   ],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "outputs": [],
   "source": [],
   "metadata": {
    "collapsed": false,
    "pycharm": {
     "name": "#%%\n"
    }
   }
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 2
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython2",
   "version": "2.7.6"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 0
}