Working as Lead researcher @datavisyn on information visualization in life sciences. Lecturer. Web Developer.
viewof activeFilters = Inputs.checkbox(["US cities"], {label: "Filter"})
filteredData = (activeFilters.includes("US cities")) ? data.filter((d) => d.location.country === 'US') : data
chart = BarChart(filteredData, {chartHeight: 350})
function BarChart(data, {
chartWidth = 800,
chartHeight = 600,
marginTop = 40,
marginBottom = 10,
marginLeft = 120,
marginRight = 20,
barHeight = 25
} = {}) {
const width = chartWidth - marginLeft - marginRight;
const height = chartHeight - marginTop - marginBottom;
// Creates sources <svg> element
const svg = d3.create("svg")
.attr('width', width + marginLeft + marginRight)
.attr('height', height + marginTop + marginBottom);
// Group used to enforce margin
const g = svg.append('g').attr('transform', `translate(${marginLeft},${marginTop})`);
// Scales setup
const xScale = d3.scaleLinear().range([0, width]).domain([0, d3.max(data, (d) => d.temperature)]);
const yScale = d3.scaleBand().rangeRound([0, height]).paddingInner(0.1).domain(data.map((d) => d.location.city));
// Axis setup
const xAxis = d3.axisTop().scale(xScale);
g.append('g').attr('class','x axis').call(xAxis);
const yAxis = d3.axisLeft().scale(yScale);
g.append('g').attr('class','y axis').call(yAxis);
// Render the chart with new data
// DATA JOIN use the key argument for ensurign that the same DOM element is bound to the same data-item
const rect = g.selectAll('rect').data(data, (d) => d.location.city).join(
// ENTER
// new elements
(enter) => {
const rect_enter = enter.append('rect').attr('x', 0);
rect_enter.append('title');
return rect_enter;
},
// UPDATE
// update existing elements
(update) => update,
// EXIT
// elements that aren't associated with data
(exit) => exit.remove()
);
// ENTER + UPDATE
// both old and new elements
rect.transition()
.attr('height', yScale.bandwidth())
.attr('width', (d) => xScale(d.temperature))
.attr('y', (d) => yScale(d.location.city));
rect.select('title').text((d) => d.location.city);
return svg.node();
}
<style>
rect {
fill: steelblue;
fill-opacity: 0.8;
}
rect:hover {
fill-opacity: 1;
}
.axis {
font-size: smaller;
}
</style>
data = FileAttachment("weather.json").json()
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
