{ "cells": [ { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "%matplotlib inline" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# Selection of data\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "import pandas as pd\nimport numpy as np\n\n\ndates = pd.date_range(\"20220501\", periods=6)\ndataFrame = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list(\"ABCD\"))" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "**Getting data**\n\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame[\"A\"]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame[0:3]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame[\"20220501\":\"20220502\"]" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "**Selection by label **\n\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.loc[dates[0]]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.loc[:, [\"A\", \"B\"]]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.loc[\"20220501\":\"20220502\", [\"A\", \"B\"]]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.loc[\"20220501\", [\"A\", \"B\"]]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.loc[dates[0], \"A\"]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.at[dates[0], \"A\"]" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "**Selection by position**\n\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iloc[3]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iloc[3:5, 0:2]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iloc[[1, 2, 4], [0, 2]]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iloc[1:3, :]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iloc[:, 1:3]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iloc[1, 1]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iat[1, 1]" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "**Boolean indexing**\n\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame[dataFrame[\"A\"] > 0]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame[dataFrame > 0]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame2 = dataFrame.copy()\ndataFrame2[\"E\"] = [\"one\", \"one\", \"two\", \"three\", \"four\", \"three\"]" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame2[dataFrame2[\"E\"].isin([\"two\", \"four\"])]" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "**Setting data**\n\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "series = pd.Series([1, 2, 3, 4, 5, 6], index=pd.date_range(\"20130102\", periods=6))\ndataFrame[\"F\"] = series" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.at[dates[0], \"A\"] = 0" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.iat[0, 1] = 0" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame.loc[:, \"D\"] = np.array([5] * len(dataFrame))" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "dataFrame2 = dataFrame.copy()\ndataFrame2[dataFrame2 > 0] = -dataFrame2" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.8.10" } }, "nbformat": 4, "nbformat_minor": 0 }