Grabbing census tracts around Oakland, messing with Turf

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	<title>Untitled</title>
	<script src="https://code.jquery.com/jquery-1.11.2.min.js" charset="utf-8"></script>
	<script src="modestmaps.min.js" charset="utf-8"></script>
	<script src="turf.min.js" charset="utf-8"></script>
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<ul>
	<li><a href="https://github.com/censusreporter/census-api/blob/master/API.md">Census Reporter API docs</a></li>
	<li><a href="https://censusreporter.org/profiles/16000US0653000-oakland-ca/">Page for single feature</a></li>
	<li><a href="https://api.censusreporter.org/1.0/geo/tiger2013/16000US0653000">JSON for single feature</a></li>
	<li><a href="https://api.censusreporter.org/1.0/geo/tiger2013/tiles/140/12/656/1582.geojson">Tile of tracts</a></li>
	<li><a href="https://api.censusreporter.org/1.0/geo/show/tiger2013?geo_ids=14000US06001401000,14000US06001401400">Pair of selected features</a></li>
	<li><a href="https://api.censusreporter.org/1.0/data/show/acs2013_5yr?table_ids=B13016&amp;geo_ids=04000US55">Data for one feature</a></li>
</ul>

// Basic GMaps projection
    var π = Math.PI,
        zoom = 12,
        xform = MM.deriveTransformation(-π,  π, 0, 0, π,  π, 1, 0, -π, -π, 0, 1),
        proj = new MM.MercatorProjection(0, xform),
        api_base_href = 'https://api.censusreporter.org/1.0';
    
    function announce(xhr, settings)
    {
        console.log('Getting ' + settings.url);
    }

console.log('Yo');
    
    var geoid = '16000US0653000', // city of Oakland
        url = api_base_href+'/geo/tiger2013/'+geoid+'?geom=true';
    
    console.log('...');
    
    var result = jQuery.ajax(url, {async: false, beforeSend: announce}),
        display_name = result.responseJSON.properties.display_name,
        extent = turf.extent(result.responseJSON);
    
    console.log(extent);
    
    var nw = new MM.Location(extent[3], extent[0]),
        se = new MM.Location(extent[1], extent[2]),
        ul = proj.locationCoordinate(nw).zoomTo(zoom).container(),
        lr = proj.locationCoordinate(se).zoomTo(zoom).container();
        
    var tiles = [],
        tracts = {},
        count = 0;
    
    for(var y = ul.row; y <= lr.row; y += 1)
    {
        for(var x = ul.column; x <= lr.column; x += 1)
        {
            var tile = zoom+'/'+x+'/'+y;
            tiles[tile] = api_base_href+'/geo/tiger2013/tiles/140/'+tile+'.geojson';
        }
    }
    
    for(var tile in tiles)
    {
        var url = tiles[tile],
            result = jQuery.ajax(url, {async: false, beforeSend: announce});
        
        console.log('There are ' + result.responseJSON.features.length + ' tracts');
        
        for(var i = 0; i < result.responseJSON.features.length; i += 1)
        {
            var feature = result.responseJSON.features[i],
                properties = feature.properties;
            
            if(tracts[properties.geoid] != undefined)
            {
                continue;
            }

tracts[properties.geoid] = feature;
            count += 1;
        }
    }
    
    document.write('<p>Loaded ' + count + ' census tracts in and around ' + display_name + ' (' + geoid + ').</p>');
    
    function number(value)
    {
        var string = value.toString();
        
        while(string.match(/^\d+\d\d\d\b/))
        {
            string = string.replace(/^(\d+)(\d\d\d\b)/, '$1,$2');
        }
        
        return string;
    }
    
    function percent(numerator, denominator, precision)
    {
        return parseFloat((100 * numerator / denominator).toPrecision(precision));
    }
    
    function show_population(estimate, error)
    {
        if(error == undefined)
            return number(estimate);

return number(estimate) + ' ± ' + number(error) + ' (' + percent(error, estimate, 2) + '%)';
    }
    
    function show_income(estimate, error)
    {
        if(error == undefined)
            return '$' + number(estimate);

return '$' + number(estimate) + ' ± $' + number(error) + ' (' + percent(error, estimate, 2) + '%)';
    }
    
    function show_percentage(estimate, error)
    {
        if(error == undefined)
            return number(estimate) + '%';

return estimate + '% ± ' + error + '%';
    }
    
    var tracts = {'14000US06001401000': tracts['14000US06001401000']}; // Longfellow
    
    for(var geoid in tracts)
    {
        var url = api_base_href+'/data/show/acs2013_5yr?table_ids=B01003,B03002,B19013,B19301&geo_ids='+geoid,
            result = jQuery.ajax(url, {async: false, beforeSend: announce}),
            tables = result.responseJSON.tables,
            data = result.responseJSON.data;
        
        for(var geoid in data)
        {
            document.write('<h2><a href="https://censusreporter.org/profiles/'+geoid+'">'+tracts[geoid].properties.name+'</a></h2>');
            document.write('<ul>');
        
            var total_population = data[geoid]['B01003'].estimate['B01003001'],
                total_population_err = data[geoid]['B01003'].error['B01003001'],
                hispanic_population = data[geoid]['B03002'].estimate['B03002012'],
                hispanic_population_err = data[geoid]['B03002'].error['B03002012'],
                hispanic_percent = percent(hispanic_population, total_population, 2),
                hispanic_percent_err = percent(hispanic_population_err, total_population, 2),
                white_population = data[geoid]['B03002'].estimate['B03002003'],
                white_population_err = data[geoid]['B03002'].error['B03002003'],
                white_percent = percent(white_population, total_population, 2),
                white_percent_err = percent(white_population_err, total_population, 2),
                black_population = data[geoid]['B03002'].estimate['B03002004'],
                black_population_err = data[geoid]['B03002'].error['B03002004'],
                black_percent = percent(black_population, total_population, 2),
                black_percent_err = percent(black_population_err, total_population, 2),
                asian_population = data[geoid]['B03002'].estimate['B03002006'],
                asian_population_err = data[geoid]['B03002'].error['B03002006'],
                asian_percent = percent(asian_population, total_population, 2),
                asian_percent_err = percent(asian_population_err, total_population, 2),
                other_population = data[geoid]['B03002'].estimate['B03002005'] + data[geoid]['B03002'].estimate['B03002007'] + data[geoid]['B03002'].estimate['B03002008'] + data[geoid]['B03002'].estimate['B03002009'],
                other_population_err = undefined,
                other_percent = percent(other_population, total_population, 2),
                other_percent_err = undefined,
                medhouse_income = data[geoid]['B19013'].estimate['B19013001'],
                medhouse_income_err = data[geoid]['B19013'].error['B19013001'],
                percapita_income = data[geoid]['B19301'].estimate['B19301001'],
                percapita_income_err = data[geoid]['B19301'].error['B19301001'];
            
            document.write('<li>Total population: ' + show_population(total_population, total_population_err) + '</li>');
            document.write('<li>Hispanic population: ' + show_population(hispanic_population, hispanic_population_err) + '</li>');
            document.write('<li>White population: ' + show_population(white_population, white_population_err) + '</li>');
            document.write('<li>Black population: ' + show_population(black_population, black_population_err) + '</li>');
            document.write('<li>Asian population: ' + show_population(asian_population, asian_population_err) + '</li>');
            document.write('<li>Other population: ' + show_population(other_population, other_population_err) + '</li>');
            document.write('<li>Median household income: ' + show_income(medhouse_income, medhouse_income_err) + '</li>');
            document.write('<li>Per capita income: ' + show_income(percapita_income, percapita_income_err) + '</li>');
            document.write('<li>Hispanic percent: ' + show_percentage(hispanic_percent, hispanic_percent_err) + '</li>');
            document.write('<li>White percent: ' + show_percentage(white_percent, white_percent_err) + '</li>');
            document.write('<li>Black percent: ' + show_percentage(black_percent, black_percent_err) + '</li>');
            document.write('<li>Asian percent: ' + show_percentage(asian_percent, asian_percent_err) + '</li>');
            document.write('<li>Other percent: ' + show_percentage(other_percent, other_percent_err) + '</li>');

document.write('</ul>');
        }
        
        break;
    }
    
</script>

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