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shimizukawa/Pandas, __getitem__, loc, iloc, ix.ipynb

Created August 8, 2017 04:46
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Pandas, __getitem__, loc, iloc, ix.ipynb
{
"cells": [
{
"cell_type": "code",
"execution_count": 1,
"metadata": {
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},
"outputs": [],
"source": [
"import pandas as pd"
]
},
{
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"execution_count": 2,
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},
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"source": [
"df = pd.DataFrame({'A': [1,2,3], 'B': [4,5,6], 'C': [7,8,9], 'D': [10,11,12]})"
]
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"<div>\n",
"<style>\n",
" .dataframe thead tr:only-child th {\n",
" text-align: right;\n",
" }\n",
"\n",
" .dataframe thead th {\n",
" text-align: left;\n",
" }\n",
"\n",
" .dataframe tbody tr th {\n",
" vertical-align: top;\n",
" }\n",
"</style>\n",
"<table border=\"1\" class=\"dataframe\">\n",
" <thead>\n",
" <tr style=\"text-align: right;\">\n",
" <th></th>\n",
" <th>A</th>\n",
" <th>B</th>\n",
" <th>C</th>\n",
" <th>D</th>\n",
" </tr>\n",
" </thead>\n",
" <tbody>\n",
" <tr>\n",
" <th>0</th>\n",
" <td>1</td>\n",
" <td>4</td>\n",
" <td>7</td>\n",
" <td>10</td>\n",
" </tr>\n",
" <tr>\n",
" <th>1</th>\n",
" <td>2</td>\n",
" <td>5</td>\n",
" <td>8</td>\n",
" <td>11</td>\n",
" </tr>\n",
" <tr>\n",
" <th>2</th>\n",
" <td>3</td>\n",
" <td>6</td>\n",
" <td>9</td>\n",
" <td>12</td>\n",
" </tr>\n",
" </tbody>\n",
"</table>\n",
"</div>"
],
"text/plain": [
" A B C D\n",
"0 1 4 7 10\n",
"1 2 5 8 11\n",
"2 3 6 9 12"
]
},
"execution_count": 3,
"metadata": {},
"output_type": "execute_result"
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"df"
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"outputs": [
{
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"<div>\n",
"<style>\n",
" .dataframe thead tr:only-child th {\n",
" text-align: right;\n",
" }\n",
"\n",
" .dataframe thead th {\n",
" text-align: left;\n",
" }\n",
"\n",
" .dataframe tbody tr th {\n",
" vertical-align: top;\n",
" }\n",
"</style>\n",
"<table border=\"1\" class=\"dataframe\">\n",
" <thead>\n",
" <tr style=\"text-align: right;\">\n",
" <th></th>\n",
" <th>B</th>\n",
" <th>D</th>\n",
" </tr>\n",
" </thead>\n",
" <tbody>\n",
" <tr>\n",
" <th>0</th>\n",
" <td>4</td>\n",
" <td>10</td>\n",
" </tr>\n",
" <tr>\n",
" <th>1</th>\n",
" <td>5</td>\n",
" <td>11</td>\n",
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" <tr>\n",
" <th>2</th>\n",
" <td>6</td>\n",
" <td>12</td>\n",
" </tr>\n",
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"</table>\n",
"</div>"
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"text/plain": [
" B D\n",
"0 4 10\n",
"1 5 11\n",
"2 6 12"
]
},
"execution_count": 4,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"# B列とD列のみ取り出したdataframe\n",
"df[['B', 'D']]"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {},
"outputs": [
{
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"<div>\n",
"<style>\n",
" .dataframe thead tr:only-child th {\n",
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" text-align: left;\n",
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"</style>\n",
"<table border=\"1\" class=\"dataframe\">\n",
" <thead>\n",
" <tr style=\"text-align: right;\">\n",
" <th></th>\n",
" <th>B</th>\n",
" <th>D</th>\n",
" </tr>\n",
" </thead>\n",
" <tbody>\n",
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" <th>0</th>\n",
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"</table>\n",
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"text/plain": [
" B D\n",
"0 4 10\n",
"1 5 11\n",
"2 6 12"
]
},
"execution_count": 7,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"# B列とD列のみ取り出したdataframe、行も指定がいる\n",
"df.loc[:, ['B', 'D']]"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {},
"outputs": [
{
"data": {
"text/html": [
"<div>\n",
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" .dataframe thead tr:only-child th {\n",
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" text-align: left;\n",
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"text/plain": [
" B D\n",
"0 4 10\n",
"1 5 11\n",
"2 6 12"
]
},
"execution_count": 9,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"# B列とD列のみ取り出したdataframe、列の名前じゃなく位置で指定。行も指定がいる\n",
"df.iloc[:, [1, 3]]"
]
},
{
"cell_type": "code",
"execution_count": 10,
"metadata": {},
"outputs": [
{
"name": "stderr",
"output_type": "stream",
"text": [
"/Users/shimizukawa/bp/triumph/ipynb/.venv/lib/python3.6/site-packages/ipykernel_launcher.py:2: DeprecationWarning: \n",
".ix is deprecated. Please use\n",
".loc for label based indexing or\n",
".iloc for positional indexing\n",
"\n",
"See the documentation here:\n",
"http://pandas.pydata.org/pandas-docs/stable/indexing.html#ix-indexer-is-deprecated\n",
" \n"
]
},
{
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"<div>\n",
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" text-align: left;\n",
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"\n",
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" vertical-align: top;\n",
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"</style>\n",
"<table border=\"1\" class=\"dataframe\">\n",
" <thead>\n",
" <tr style=\"text-align: right;\">\n",
" <th></th>\n",
" <th>B</th>\n",
" <th>D</th>\n",
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"text/plain": [
" B D\n",
"0 4 10\n",
"1 5 11\n",
"2 6 12"
]
},
"execution_count": 10,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"# ixは位置でも名前でも指定できるやつだけど、Deprecated\n",
"df.ix[:, [1, 3]]"
]
},
{
"cell_type": "code",
"execution_count": 11,
"metadata": {},
"outputs": [
{
"data": {
"text/html": [
"<div>\n",
"<style>\n",
" .dataframe thead tr:only-child th {\n",
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"\n",
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" text-align: left;\n",
" }\n",
"\n",
" .dataframe tbody tr th {\n",
" vertical-align: top;\n",
" }\n",
"</style>\n",
"<table border=\"1\" class=\"dataframe\">\n",
" <thead>\n",
" <tr style=\"text-align: right;\">\n",
" <th></th>\n",
" <th>B</th>\n",
" <th>D</th>\n",
" </tr>\n",
" </thead>\n",
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"</table>\n",
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"text/plain": [
" B D\n",
"0 4 10\n",
"1 5 11\n",
"2 6 12"
]
},
"execution_count": 11,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"# ixはDeprecated\n",
"df.ix[:, ['B', 'D']]"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
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},
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"display_name": "Python 3",
"language": "python",
"name": "python3"
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"version": 3
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"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.6.1"
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"nbformat_minor": 2
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