This example is based on the canonical simple bar chart example, but with a minor twist - a data update is added to the chart in a Jupyter cell below the chart, which updates the chart with a transition.
In [1]:
from IPython.core.display import display, HTML
from string import Template
import pandas as pd
import json, random
In [2]:
HTML('<script src="lib/d3/d3.min.js"></script>')
Out[2]:
In [3]:
html_template = Template('''
<style> $css_text </style>
<div id="graph-div"></div>
<script> $js_text </script>
''')
In [4]:
css_text = '''
.bar {
fill: steelblue;
}
.bar:hover {
fill: brown;
}
.axis {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.x.axis path {
display: none;
}
'''
In [5]:
js_text_template = Template('''
var margin = {top: 20, right: 20, bottom: 30, left: 40},
width = 500 - margin.left - margin.right,
height = 300 - margin.top - margin.bottom;
var x = d3.scale.ordinal()
.rangeRoundBands([0, width], .1);
var y = d3.scale.linear()
.range([height, 0]);
var xAxis = d3.svg.axis()
.scale(x)
.orient("bottom");
var yAxis = d3.svg.axis()
.scale(y)
.orient("left");
var svg = d3.select("#graph-div").append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
var data = $data ;
x.domain(data.map(function(d) { return d.letter; }));
y.domain([0, d3.max(data, function(d) { return d.y; })]);
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
svg.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function(d) { return x(d.letter); })
.attr("width", x.rangeBand())
.attr("y", function(d) { return y(d.y); })
.attr("height", function(d) { return height - y(d.y); });
''')
In [6]:
js_text_template_2 = Template('''
var bars = svg.selectAll(".bar").data($data);
bars
.transition()
.attr("y", function(d) { return y(d.y); })
.attr("height", function(d) { return height - y(d.y); });
''')
In [7]:
data = pd.DataFrame({'letter': ['A','B','C','D'], 'y': [1,1,1,1]})
data.head()
Out[7]:
In [8]:
js_text = js_text_template.substitute({'data': json.dumps(data.to_dict(orient='records'))})
HTML(html_template.substitute({'css_text': css_text, 'js_text': js_text}))
Out[8]:
In [9]:
data['y'] = [random.uniform(0,1) for d in data['y']]
js_text = js_text_template_2.substitute({'data': json.dumps(data.to_dict(orient='records'))})
HTML('<script>' + js_text + '</script>')
Out[9]:
Re-run this last cell (ctrl-Enter lets you run it and stay put) and watch it transition the graph above it.