31:T463,function groupByField(data, groupField) { let groupData, date, location, arrested, info, results = {}; const dateFilter = arrow.predicate.custom(i => { const date = toDate(data.getColumn('Date').get(i)); return (date.getMonth() <= months.length); }, b => 1); data.filter(dateFilter) .scan((index) => { const groupFieldData = groupData(index); const groupArray = results[groupFieldData]; if (!groupArray) { results[groupFieldData] = []; } const dataRecord = {}; dataRecord[groupField] = groupFieldData; dataRecord['date'] = toDate(date(index)); dataRecord['location'] = location(index); dataRecord['arrested'] = arrested(index); dataRecord['info'] = info(index); results[groupFieldData].push(dataRecord); }, (batch) => { groupData = arrow.predicate.col(groupField).bind(batch); date = arrow.predicate.col('Date').bind(batch); location = arrow.predicate.col('LocationDescription').bind(batch); arrested = arrow.predicate.col('Arrest').bind(batch); info = arrow.predicate.col('Description').bind(batch); }); return results; }32:[] 2f:{"title":"Chicago Crimes by Type","cells":[{"id":0,"value":"md`# Chicago Crimes by Type\n\nCompanion notebook for the\n[2018 Chicago Crimes Heatmap](https://beta.observablehq.com/@randomfractals/deck-gl-heatmap)\nand\n[Intro to Using Apache Arrow JS with Large Datasets](https://beta.observablehq.com/@randomfractals/apache-arrow)\n`","pinned":false,"hidden":false,"mode":"ojs"},{"id":45,"value":"html `\n

${Object.keys(crimeData)\n .map(crimeType => textCloud(crimeData, crimeType))\n .sort((a, b) => a.count - b.count)\n .map(c => c.html)}\n

Total Crimes: ${Object.keys(crimeData)\n .map(key => crimeData[key].length)\n .reduce((total, num) => total + num)\n .toLocaleString()}\n

\n`","pinned":true,"hidden":false,"mode":"ojs"},{"id":201,"value":"function textCloud(data, crimeType) {\n console.log('graphing', crimeType, '...');\n const count = data[crimeType].length;\n const div = html`

\n ${crimeType}\n (${count.toLocaleString()})\n

`; \n return {html: div, count};\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":274,"value":"monthlyCrimeData = Object.keys(crimeData)\n .map(crimeType => {\n return {'crimeType': crimeType, 'monthly': groupByMonth(crimeData, crimeType)};\n })","pinned":true,"hidden":false,"mode":"ojs"},{"id":326,"value":"months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'July', 'August']","pinned":false,"hidden":false,"mode":"ojs"},{"id":222,"value":"// note: this is monthly hacky AF! :(\nfunction groupByMonth(data, groupField) {\n let monthly = {};\n data[groupField].map(data => {\n const month = data.date.getMonth();\n if (month <= months.length) {\n if (!monthly[months[month]]) {\n monthly[months[month]] = [];\n }\n monthly[months[month]].push(data);\n }\n });\n return monthly;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":300,"value":"theft = plotMonthlyData(crimeData['THEFT'], 'theft')","pinned":true,"hidden":false,"mode":"ojs"},{"id":297,"value":"function plotMonthlyData(data, type, width=180, height=180) {\n return vegalite({\n data: {values: data},\n mark: 'bar',\n width: width,\n height: height,\n encoding: {\n x: {timeUnit: 'month', field: 'date', type: 'ordinal',\n axis: {title: `${type.toLowerCase()} (${data.length.toLocaleString()})`}\n },\n y: {aggregate: 'count', field: '*', type: 'quantitative',\n axis: {title: false}\n },\n color: {value: '#30a2da'} \n },\n });\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":163,"value":"md `## Crime Data`","pinned":false,"hidden":false,"mode":"ojs"},{"id":190,"value":"dataUrl = 'https://raw.githubusercontent.com/RandomFractals/ChicagoCrimes/master/data/2018/chicago-crimes-2018.arrow'","pinned":false,"hidden":false,"mode":"ojs"},{"id":193,"value":"dataTable = loadData(dataUrl).then(buffer => arrow.Table.from(new Uint8Array(buffer)))","pinned":false,"hidden":false,"mode":"ojs"},{"id":24,"value":"crimeData = groupByField(dataTable, 'PrimaryType')","pinned":true,"hidden":false,"mode":"ojs"},{"id":170,"value":"$31","pinned":true,"hidden":false,"mode":"ojs"},{"id":9,"value":"import {loadData, range, getMarkdown, toDate} from '@randomfractals/apache-arrow'","pinned":true,"hidden":false,"mode":"ojs"},{"id":185,"value":"arrow = require('apache-arrow@0.3.1')","pinned":true,"hidden":false,"mode":"ojs"},{"id":286,"value":"vegalite = require(\"@observablehq/vega-lite@0.1\")","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W32","stdlib":"1","titling":"auto"}