[Solved]-path not drawn in d3 stacked area chart-d3.js

The path has no d attribute. Some debugging in the code shows, that the function areaFcn returns undefined. Change it to this and it'll work:

var areaFcn = d3.svg.area()
.x(function(d, i) {
    return xScaleT(d.t); })
.y0(function(d) {
    return yScale(d.y0); })
.y1(function(d) {
    return yScale(d.y0 + d.y); });