(x, y, z) triplets for heatmaps fails for this example

[chriddyp]

var data = [{
  x: [2, 4, 5],
  y: [1, 1, 1],
  z: [1, 2, 3],
  type: 'heatmap'
}];
var layout = {
  title: '(x, y, z) triplets'
};

Plotly.newPlot('myDiv', data, layout);

Codepen: http://codepen.io/chriddyp/pen/yYdYvp

Trace (iy=-1):