d3js animated horizontal chart improvements - d3.js

Question

I am creating a horizontal animated d3 chart. How do you reverse the x axis and position the bars in a more dynamic way.
Are the bars the correct width or is the xaxis scale correct? Using d3 version 4
//horizontal work in progress
http://jsfiddle.net/ueg3bjf7/
//vertical chart code this is based from
http://jsfiddle.net/myf1zhar/
$(document).ready(function() {
var $this = $(".barchart");
var w = $this.data("width");
var h = $this.data("height");
var data = $this.data("data");
var data = [{
"label": "Apples",
"value": 100
},
{
"label": "Pears",
"value": 120
},
{
"label": "Bananas",
"value": 20
}
];
var configurations = $this.data("configurations");
function colores_google(n) {
var colores_g = ["#f7b363", "#448875", "#2b2d39", "#c12f39", "#f8dd2f", "#1b91dc"];
return colores_g[n % colores_g.length];
}
//asess the margin bottom for the chart based on the max char label
var charLabelCount = [];
data.map(function(d) {
var labelStr = d.label.toString();
charLabelCount.push(labelStr.length);
})
var maxChars = charLabelCount.reduce(function(a, b) {
return Math.max(a, b);
});
var bottomMarg = 60;
if (maxChars > 15) {
bottomMarg = 170;
}
//bottom margin calculation
var margin = {
top: 15,
right: 20,
bottom: bottomMarg,
left: 40
},
width = w - margin.left - margin.right,
height = h - margin.top - margin.bottom;
var x = d3.scaleBand()
.range([0, width]);
var y = d3.scaleLinear()
.range([height, 0]);
var yAxis = d3.axisBottom(y);
var xAxis = d3.axisLeft(x);
var svg = d3.select($this[0])
.append("svg")
.attr("width", w)
.attr("height", h)
.attr("viewBox", "0 0 " + w + " " + h)
.attr("preserveAspectRatio", "xMidYMid meet")
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")")
.attr("class", "barchartg");
function sortBy(array, key) {
var sorted = array.sort(function(a, b) {
return parseFloat(b[key]) - parseFloat(a[key]);
});
return sorted;
}
var sortedMax = 45;
if (configurations) {
if (configurations[0]["maxValue"]) {
sortedMax = configurations[0]["maxValue"] + 5;
}
} else {
sortedMax = sortBy(data, "value")[0]["value"] + 5;
}
x.domain(data.map(function(d) {
return d.label;
}));
y.domain([0, sortedMax]);
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0,25)")
.call(xAxis);
svg.selectAll(".x.axis text")
.attr("transform", "rotate(-60) translate(-5,-5)")
.style("text-anchor", "end");
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("");
svg.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", "bar")
.attr("fill", function(d, i) {
return colores_google(i);
})
.attr("x", function(d) {
return 0;
})
.attr("width", function(d) {
return d.value;
})
.attr("y", function(d, i) {
return 45 + (i * 90);
})
.attr("height", function(d) {
return 50;
});
d3.selectAll("rect").transition()
.duration(500)
.delay(function(d, i) {
return 500 * i;
})
.attr("width", function(d) {
return 0;
})
setTimeout(function() {
d3.selectAll("rect").transition()
.duration(500)
.delay(function(d, i) {
return 600 * (3 - i);
})
.attr("width", function(d) {
return d.value;
})
}, 2000);
});

Answer 1

I will try to answer your questions.
How do you reverse the x axis
You have to change the domain of the axis
y.domain([sortedMax, 0]);
position the bars
You have to translate the axis to the width of your graph
svg.append("g").attr("transform", "translate(0, 300)").attr("class", "y axis")
Are the bars the correct width or is the xaxis scale correct?
You have to use a multiplier to calculate the width of each bar, using the max width of your graph and your max value. I have added the 25 pixels of the translate of the x axis
var mult = (w + 25) / sortedMax;
...
svg.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", "bar")
.attr("fill", function(d, i) {
return colores_google(i);
})
.attr("x", function(d) {
return 0;
})
.attr("width", function(d) {
return d.value * mult;
})
.attr("y", function(d, i) {
return 45 + (i * 90);
})
.attr("height", function(d) {
return 50;
});
...
setTimeout(function() {
d3.selectAll("rect").transition()
.duration(500)
.delay(function(d, i) {
return 600 * (3 - i);
})
.attr("width", function(d) {
return d.value * mult;
})
}, 2000);
You can see the result in this fiddle http://jsfiddle.net/jfLgawue/65/