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color = d3.scaleSequential(d3.interpolateYlOrRd).domain([d3.min(data, d => d.value), d3.max(data, d => d.value)])
data = dailyCounts
dataTable = loadData(dataUrl).then(buffer => arrow.Table.from(new Uint8Array(buffer)))
dailyData = groupByDay(dataTable, crimeType)
dailyCounts = Object.keys(dailyData)
.map(day => {
return {date: new Date(new Date(day).getTime() + timezoneOffset), value: dailyData[day].length};
})
timezoneOffset = (new Date().getTimezoneOffset() + 60) * 60 * 1000 // note: +60 for daylight saving time
function groupByDay(dataTable, crimeType) {
let groupData, date, location, arrested, info, results = {};
const dataFilter = arrow.predicate.custom(i => {
const date = toDate(dataTable.getColumn('Date').get(i));
const primaryType = dataTable.getColumn('PrimaryType').get(i);
return ((crimeType === '' || primaryType === crimeType) &&
date.getMonth() <= 8); // through August
}, b => 1);
dataTable.filter(dataFilter)
.scan((index) => {
const day = toDate(date(index)).toISOString().substring(0, 10); // ISO date string
if (!results[day]) {
results[day] = [];
}
const dataRecord = {};
dataRecord['date'] = toDate(date(index));
dataRecord['location'] = location(index);
dataRecord['arrested'] = arrested(index);
dataRecord['info'] = info(index);
results[day].push(dataRecord);
}, (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;
}
import {loadData, toDate} from '@randomfractals/apache-arrow'
arrow = require('apache-arrow@0.3.1')
import {select} from "@jashkenas/inputs"
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