paulo@89: var myChart;
paulo@89: var myData;
paulo@89: var showCorrBtn = document.getElementById('showcorr');
paulo@89: 
paulo@89: nv.addGraph(function() {
paulo@89:   myChart = nv.models.scatterChart()
paulo@89:                 .showLegend(false)
paulo@89:                 .showDistX(true)
paulo@89:                 .showDistY(true)
paulo@89:                 .xDomain([-1, 1])
paulo@89:                 .yDomain([-1, 1])
paulo@89:                 .duration(350)
paulo@89:                 .color(d3.scale.category10().range());
paulo@89:   myChart.tooltip.contentGenerator(function(data) {
paulo@89:     return '(' + data.point.x.toFixed(2) + ', ' + data.point.y.toFixed(2) + ')';
paulo@89:   });
paulo@89: 
paulo@89:   myChart.xAxis.tickFormat(d3.format('.02f'));
paulo@89:   myChart.yAxis.tickFormat(d3.format('.02f'));
paulo@89: 
paulo@89:   reload();
paulo@89: 
paulo@89:   return myChart;
paulo@89: });
paulo@89: 
paulo@89: 
paulo@89: function randomData(groups, points) {
paulo@89:   var data = [],
paulo@89:       shapes = ['circle', 'cross', 'triangle-up', 'triangle-down', 'diamond', 'square'],
paulo@89:       random = d3.random.normal();
paulo@89: 
paulo@89:   for (i = 0; i < groups; i++) {
paulo@89:     data.push({
paulo@89:       key: 'Group ' + i,
paulo@89:       values: []
paulo@89:     });
paulo@89: 
paulo@89:     for (j = 0; j < points; j++) {
paulo@89:       data[i].values.push({
paulo@89:         x: random(),
paulo@89:         y: random(),
paulo@89:         size: Math.random(),
paulo@89:         shape: (Math.random() > 0.95) ? shapes[j % 6] : 'circle'
paulo@89:       });
paulo@89:     }
paulo@89:   }
paulo@89: 
paulo@89:   return data;
paulo@89: }
paulo@89: 
paulo@89: function myDataGen() {
paulo@89:   var data = [];
paulo@89:   var values = [];
paulo@89:   var n = 25;
paulo@89:   var m = 2*Math.random() - 1.0;
paulo@89:   var dv = Math.random();
paulo@89:   var normal = d3.random.normal(0.0, dv)
paulo@89: 
paulo@89:   for (i = 0; i < n; i++) {
paulo@89:     var x = i/n + 0.5*normal() - 0.5;
paulo@89:     var y = m*x + normal();
paulo@89:     values.push({
paulo@89:       x: x,
paulo@89:       y: y,
paulo@89:       size: 2.0,
paulo@89:       shape: 'circle',
paulo@89:     });
paulo@89:   }
paulo@89: 
paulo@89:   data.push({
paulo@89:     //key: 'Points',
paulo@89:     values: values,
paulo@89:     //slope: m,
paulo@89:     //intercept: 0.001,
paulo@89:   })
paulo@89: 
paulo@89:   return data;
paulo@89: }
paulo@89: 
paulo@89: function corr(values) {
paulo@89:   var x_a = [];
paulo@89:   var y_a = [];
paulo@89: 
paulo@89:   for (i = 0; i < values.length; i++) {
paulo@89:     x_a.push(values[i].x);
paulo@89:     y_a.push(values[i].y);
paulo@89:   }
paulo@89: 
paulo@89:   return ss.sampleCorrelation(x_a, y_a);
paulo@89: }
paulo@89: 
paulo@89: function lr(values) {
paulo@89:   var x_y = [];
paulo@89: 
paulo@89:   for (i = 0; i < values.length; i++) {
paulo@89:     x_y.push([values[i].x, values[i].y]);
paulo@89:   }
paulo@89: 
paulo@89:   return ss.linearRegression(x_y);
paulo@89: }
paulo@89: 
paulo@89: function print_corr() {
paulo@89:   console.log('corr = ' + corr(myData[0].values))
paulo@89: }
paulo@89: 
paulo@89: function print_lr() {
paulo@89:   var lro = lr(myData[0].values);
paulo@89:   console.log('m = ' + lro.m);
paulo@89:   console.log('b = ' + lro.b);
paulo@89: }
paulo@89: 
paulo@89: function add_lr(lro, data) {
paulo@89:   data.push({
paulo@89:     values: [],
paulo@89:     slope: lro.m,
paulo@89:     intercept: lro.b,
paulo@89:   })
paulo@89: }
paulo@89: 
paulo@89: function show_corr() {
paulo@89:   var ans = corr(myData[0].values);
paulo@89:   showCorrBtn.textContent = ans.toFixed(2);
paulo@89:   showCorrBtn.onclick = reload;
paulo@89: }  
paulo@89: 
paulo@89: function reload() {
paulo@89:   myData = myDataGen();
paulo@89:   add_lr(lr(myData[0].values), myData);
paulo@89:   showCorrBtn.disabled = false;
paulo@89:   showCorrBtn.textContent = 'Show Correlation';
paulo@89:   showCorrBtn.onclick = show_corr;
paulo@89: 
paulo@89:   d3.select('#chart svg')
paulo@89:     .style('height', '95%')
paulo@89:     .datum(myData)
paulo@89:     .call(myChart);  
paulo@89: 
paulo@89:   nv.utils.windowResize(myChart.update);
paulo@89: }