d3 bar chart transition from csv - d3.js

Question

I'm a d3 novice trying to create a simple, two-series bar chart that transitions when different buttons are clicked. The original chart is constructed:
var margin = {top: 20, right: 20, bottom: 30, left: 40},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
var x0 = d3.scale.ordinal()
.rangeRoundBands([0, width], .1);
var x1 = d3.scale.ordinal();
var y = d3.scale.linear()
.range([height, 0]);
var color = d3.scale.ordinal()
.range(["#d4d4d4", "#58bd5b",]);
var xAxis = d3.svg.axis()
.scale(x0)
.orient("bottom");
var yAxis = d3.svg.axis()
.scale(y)
.orient("left")
.tickFormat(d3.format(".2s"));
var svg = d3.select("div.d3space").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 + ")");
d3.csv("/assets/data/data3.csv", function(error, data) {
var hourBuckets = d3.keys(data[0]).filter(function(key) { return key !== "Client"; });
data.forEach(function(d) {
d.hours = hourBuckets.map(function(name) { return {name: name, value: +d[name]}; });
});
x0.domain(data.map(function(d) { return d.Client; }));
x1.domain(hourBuckets).rangeRoundBands([0, x0.rangeBand()]);
y.domain([0, d3.max(data, function(d) { return d3.max(d.hours, function(d) { return d.value; }); })]);
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 6)
.attr("dy", ".71em")
.style("text-anchor", "end")
.text("Hours");
var client = svg.selectAll(".client")
.data(data)
.enter().append("g")
.attr("class", "g")
.attr("transform", function(d) { return "translate(" + x0(d.Client) + ",0)"; });
client.selectAll("rect")
.data(function(d) { return d.hours; })
.enter().append("rect")
.attr("width", x1.rangeBand())
.attr("x", function(d) { return x1(d.name); })
.attr("y", function(d) { return y(d.value); })
.attr("height", function(d) { return height - y(d.value); })
.style("fill", function(d) { return color(d.name); });
var legend = svg.selectAll(".legend")
.data(hourBuckets.slice().reverse())
.enter().append("g")
.attr("class", "legend")
.attr("transform", function(d, i) { return "translate(0," + i * 20 + ")"; });
legend.append("rect")
.attr("x", width - 18)
.attr("width", 18)
.attr("height", 18)
.style("fill", color);
legend.append("text")
.attr("x", width - 24)
.attr("y", 9)
.attr("dy", ".35em")
.style("text-anchor", "end")
.text(function(d) { return d; });
});
The csv being accessed is in the following format:
Client,Planned,Actual
ICC,25,50
RNR,50,47.5
MB,10,2.5
This chart renders as desired. The piece I am struggling with is getting this graph to transition to reflect different data when a link is clicked (link has id="fourweeks"). I have tried this onclick function:
window.onload = function() {
var a = document.getElementById("fourweeks");
var b = document.getElementById("eightweeks");
var c = document.getElementById("twelveweeks");
a.onclick = function() {
d3.csv("/assets/data/data1.csv", function(error, data) {
var hourBuckets = d3.keys(data[0]).filter(function(key) { return key !== "Client"; });
data.forEach(function(d) {
d.hours = hourBuckets.map(function(name) { return {name: name, value: +d[name]}; });
});
var client = svg.selectAll(".client")
client.selectAll("rect")
.data(function(d) { return d.hours; })
.transition()
.duration(1000)
.attr("y", function(d) { return y(d.value); })
.attr("height", function(d) { return height - y(d.value); })
});
}
}
...no dice. I can get this to work when creating / transitioning simple one-series bar charts that use list inputs, but not the multi-series csv ones. data2.csv is the exact same file as data1.csv, with the values adjusted slightly.
Thanks for your time reading - any advice?

Answer 1

First svg.selectAll(".client") returns an empty selection, because you gave these elements the class 'g' instead of 'client'.
Secondly you need to update the data of the .client-elements:
var client = svg.selectAll(".client")
.data(data);
btw. you should use selection.classed() instead of selection.attr('class')