Redrawing bar graph in d3.js when data changes - angularjs

Question

I am developing bar graph using d3.js integrating with Angularjs. The angular directive code I am using is given below . My problem is ,in my real application , the bar graph is not redrawing but its axis changes when data associated with the bar graph changes
mainApp.directive('ngDatenobargraph', function() {
return {
restrict: 'AE',
scope: {
data: '='
},
link: function (scope, element) {
var margin = {top: 10, right: 10, bottom: 40, left: 60},
width = 410 - margin.left - margin.right,
height = 230 - margin.top - margin.bottom;
var chart = d3.select(element[0])
.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 x = d3.scale.ordinal().rangeRoundBands([0, width], .1);
var tip = d3.tip()
.attr('class', 'd3-tip')
.offset([-10, 0])
.html(function(d) {
return "<span style='font-size: 13px'>Date:&nbsp</span><span style='color:red;font-size: 13px'>" + d.xValue+ "</span><br>"+
"<span style='font-size: 13px'>Net Value:&nbsp</span><span style='color:red;font-size: 13px'>" + d.yValue+ "</span><br>"+
"<span style='font-size: 13px'>Buy Value:&nbsp</span><span style='color:red;font-size: 13px'>" + d.buyValue+ "</span><br>"+
"<span style='font-size: 13px'>Sell Value:&nbsp</span><span style='color:red;font-size: 13px'>" + d.sellValue+ "</span>";
});
chart.call(tip);
//Render graph based on 'data'
scope.render = function(data) {
if(data) {
var y = d3.scale.linear()
.range([height, 0])
.domain(d3.extent(data, function(d) { return d.yValue; }))
.nice();
var xAxis = d3.svg.axis().scale(x).orient("bottom");
var yAxis = d3.svg.axis().scale(y).orient("left").ticks(7);
x.domain(data.map(function(d) { return d.xValue; }));
//Redraw the axes
chart.selectAll('g.axis').remove();
chart.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + (height) + ")")
.call(xAxis)
.selectAll("text")
.style("text-anchor", "end")
.attr("dx", "-.8em")
.attr("dy", ".15em")
.attr("transform", function(d) {
return "rotate(-20)";
});
chart.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 0-margin.left)
.attr("x",0-(height / 2))
.attr("dy", "1em")
.style("text-anchor", "middle")
.text("Net Value");
chart.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", function(d) { return d.yValue < 0 ? "bar negative" : "bar positive"; })
.attr("x", function(d) { return x(d.xValue); })
.attr("y", height)
.attr("height", 0)
.on('mouseover', tip.show)
.on('mouseout', tip.hide)
.transition().duration(2000)
.attr("y", function(d) {return y(Math.max(0, d.yValue)); })
.attr("height", function(d) {return Math.abs(y(d.yValue) - y(0)); })
// .attr("width", x.rangeBand());
.attr("width", Math.min.apply(null, [x.rangeBand()-2, 100]));
}
};
scope.$watch('data', function() {
scope.render(scope.data);
}, true);
}
};
});
I am new to d3.js . If any have solution please help me .The code in application is given http://jsfiddle.net/HB7LU/9000/