modin_bug_datetime_substraction.ipynb

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    "## With pandas"
   ]
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   "outputs": [],
   "source": [
    "import pandas as pd"
   ]
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       "                date1               date2\n",
       "0 2020-03-07 00:00:00 2020-03-07 00:00:00\n",
       "1 2020-03-07 00:01:00 2020-03-07 00:02:00\n",
       "2 2020-03-07 00:02:00 2020-03-07 00:04:00\n",
       "3 2020-03-07 00:03:00 2020-03-07 00:06:00\n",
       "4 2020-03-07 00:04:00 2020-03-07 00:08:00"
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    "# create an array of 5 dates starting at '2020-03-07', one per minute and one per two minutes\n",
    "rng_1 = pd.date_range('2020-03-07', periods=5, freq='T')\n",
    "rng_2 = pd.date_range('2020-03-07', periods=5, freq='2T')\n",
    "df = pd.DataFrame({ 'date1': rng_1, 'date2': rng_2})\n",
    "df"
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       "                date1               date2    delta\n",
       "0 2020-03-07 00:00:00 2020-03-07 00:00:00 00:00:00\n",
       "1 2020-03-07 00:01:00 2020-03-07 00:02:00 00:01:00\n",
       "2 2020-03-07 00:02:00 2020-03-07 00:04:00 00:02:00\n",
       "3 2020-03-07 00:03:00 2020-03-07 00:06:00 00:03:00\n",
       "4 2020-03-07 00:04:00 2020-03-07 00:08:00 00:04:00"
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   "source": [
    "df['delta'] = df['date2'] - df['date1']\n",
    "df"
   ]
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## With modin"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
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    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "WARNING: Not monitoring node memory since `psutil` is not installed. Install this with `pip install psutil` (or ray[debug]) to enable debugging of memory-related crashes.\n"
     ]
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     "text": [
      "FutureWarning: pandas.core.index is deprecated and will be removed in a future version.  The public classes are available in the top-level namespace.\n"
     ]
    }
   ],
   "source": [
    "import modin.pandas as mpd"
   ]
  },
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     "end_time": "2020-03-07T11:20:47.969427Z",
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       "                date1               date2\n",
       "0 2020-03-07 00:00:00 2020-03-07 00:00:00\n",
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    "# create an array of 5 dates starting at '2020-03-07', one per minute and one per two minutes\n",
    "mrng_1 = mpd.date_range('2020-03-07', periods=5, freq='T')\n",
    "mrng_2 = mpd.date_range('2020-03-07', periods=5, freq='2T')\n",
    "mdf = pd.DataFrame({ 'date1': mrng_1, 'date2': mrng_2})\n",
    "mdf"
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       "                date1               date2    delta\n",
       "0 2020-03-07 00:00:00 2020-03-07 00:00:00 00:00:00\n",
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   "source": [
    "mdf['delta'] = mdf['date2'] - mdf['date1']\n",
    "mdf"
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