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@emeeks
Last active August 13, 2018 08:40
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Brush Snapping
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
font-family: sans-serif;
color: #000;
text-rendering: optimizeLegibility;
}
.barchart {
z-index: 30;
display: block;
visibility: visible;
position: relative;
padding-top: 15px;
margin-top: 15px;
}
.axis {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.x.axis path {
display: none;
}
.resize path {
fill: #666;
fill-opacity: .8;
stroke: #000;
stroke-width: 1.5px;
}
.brush .extent {
stroke: #fff;
stroke-opacity: .6;
stroke-width: 2px;
fill-opacity: .1;
shape-rendering: crispEdges;
}
</style>
<body>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="http://d3js.org/d3.geo.projection.v0.min.js"></script>
<script src="http://d3js.org/topojson.v1.min.js"></script>
<script>
var margin = {top: 20, right: 20, bottom: 30, left: 40},
width = 960 - margin.left - margin.right,
height = 200 - margin.top - margin.bottom;
brushYearStart = 1848;
brushYearEnd = 1905;
// Scales
var x = d3.scale.ordinal().rangeRoundBands([0, width - 60], .1);
var y = d3.scale.linear().range([height, 0]);
// Prepare the barchart canvas
var barchart = d3.select("body").append("svg")
.attr("class", "barchart")
.attr("width", "100%")
.attr("height", height + margin.top + margin.bottom)
.attr("y", height - height - 100)
.append("g");
var z = d3.scale.ordinal().range(["steelblue", "indianred"]);
var brushYears = barchart.append("g")
brushYears.append("text")
.attr("id", "brushYears")
.classed("yearText", true)
.text(brushYearStart + " - " + brushYearEnd)
.attr("x", 35)
.attr("y", 12);
d3.csv("years_count.csv", function (error, post) {
// Coercion since CSV is untyped
post.forEach(function (d) {
d["frequency"] = +d["frequency"];
d["frequency_discontinued"] = +d["frequency_discontinued"];
d["year"] = d3.time.format("%Y").parse(d["year"]).getFullYear();
});
var freqs = d3.layout.stack()(["frequency", "frequency_discontinued"].map(function (type) {
return post.map(function (d) {
return {
x: d["year"],
y: +d[type]
};
});
}));
x.domain(freqs[0].map(function (d) {
return d.x;
}));
y.domain([0, d3.max(freqs[freqs.length - 1], function (d) {
return d.y0 + d.y;
})]);
// Axis variables for the bar chart
x_axis = d3.svg.axis().scale(x).tickValues([1850, 1855, 1860, 1865, 1870, 1875, 1880, 1885, 1890, 1895, 1900]).orient("bottom");
y_axis = d3.svg.axis().scale(y).orient("right");
// x axis
barchart.append("g")
.attr("class", "x axis")
.style("fill", "#000")
.attr("transform", "translate(0," + height + ")")
.call(x_axis);
// y axis
barchart.append("g")
.attr("class", "y axis")
.style("fill", "#000")
.attr("transform", "translate(" + (width - 85) + ",0)")
.call(y_axis);
// Add a group for each cause.
var freq = barchart.selectAll("g.freq")
.data(freqs)
.enter().append("g")
.attr("class", "freq")
.style("fill", function (d, i) {
return z(i);
})
.style("stroke", "#CCE5E5");
// Add a rect for each date.
rect = freq.selectAll("rect")
.data(Object)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function (d) {
return x(d.x);
})
.attr("y", function (d) {
return y(d.y0) + y(d.y) - height;
})
.attr("height", function (d) {
return height - y(d.y);
})
.attr("width", x.rangeBand())
.attr("id", function (d) {
return d["year"];
});
// Draw the brush
brush = d3.svg.brush()
.x(x)
.on("brush", brushmove)
.on("brushend", brushend);
var arc = d3.svg.arc()
.outerRadius(height / 15)
.startAngle(0)
.endAngle(function(d, i) { return i ? -Math.PI : Math.PI; });
brushg = barchart.append("g")
.attr("class", "brush")
.call(brush);
brushg.selectAll(".resize").append("path")
.attr("transform", "translate(0," + height / 2 + ")")
.attr("d", arc);
brushg.selectAll("rect")
.attr("height", height);
});
// ****************************************
// Brush functions
// ****************************************
function brushmove() {
y.domain(x.range()).range(x.domain());
b = brush.extent();
var localBrushYearStart = (brush.empty()) ? brushYearStart : Math.ceil(y(b[0])),
localBrushYearEnd = (brush.empty()) ? brushYearEnd : Math.ceil(y(b[1]));
// Snap to rect edge
d3.select("g.brush").call((brush.empty()) ? brush.clear() : brush.extent([y.invert(localBrushYearStart), y.invert(localBrushYearEnd)]));
// Fade all years in the histogram not within the brush
d3.selectAll("rect.bar").style("opacity", function(d, i) {
return d.x >= localBrushYearStart && d.x < localBrushYearEnd || brush.empty() ? "1" : ".4";
});
}
function brushend() {
var localBrushYearStart = (brush.empty()) ? brushYearStart : Math.ceil(y(b[0])),
localBrushYearEnd = (brush.empty()) ? brushYearEnd : Math.floor(y(b[1]));
d3.selectAll("rect.bar").style("opacity", function(d, i) {
return d.x >= localBrushYearStart && d.x <= localBrushYearEnd || brush.empty() ? "1" : ".4";
});
// Additional calculations happen here...
// filterPoints();
// colorPoints();
// styleOpacity();
// Update start and end years in upper right-hand corner of the map
d3.select("#brushYears").text(localBrushYearStart == localBrushYearEnd ? localBrushYearStart : localBrushYearStart + " - " + localBrushYearEnd);
}
function resetBrush() {
brush
.clear()
.event(d3.select(".brush"));
}
</script>
<div id="resetMap">
<button
id="returnBrush"
class="btn btn-default"
onclick="resetBrush()"/>Remove Brush
</div>
</body>
</html>
year frequency frequency_discontinued
1847 2 0
1848 0 0
1849 14 0
1850 46 6
1851 113 8
1852 83 23
1853 54 20
1854 98 16
1855 81 24
1856 58 17
1857 73 25
1858 101 33
1859 54 24
1860 77 40
1861 90 23
1862 80 31
1863 71 31
1864 122 38
1865 71 26
1866 121 44
1867 124 44
1868 140 54
1869 153 52
1870 190 45
1871 222 65
1872 205 53
1873 205 60
1874 225 69
1875 204 92
1876 181 89
1877 186 66
1878 296 98
1879 350 138
1880 372 135
1881 406 202
1882 428 196
1883 367 210
1884 371 157
1885 212 117
1886 298 135
1887 396 172
1888 525 189
1889 404 101
1890 573 196
1891 420 169
1892 508 198
1893 249 181
1894 375 227
1895 345 266
1896 345 145
1897 184 99
1898 386 174
1899 297 192
1900 475 212
1901 369 246
1902 358 276
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