D3 Barchart - PM10

d3_barchart_PM10.js

<script src="http://d3js.org/d3.v3.min.js" charset="utf-8"> </script>

<script>

var data0 = [];
var data  = [];

var jsonurl = "https://USERNAME.cloudant.com/DB/_design/myView/_view/test?group_level=2";

/* Structur {"key":[year,month],"value":[mean,lenght]}

{"rows":[
{"key":[2008,1],"value":[43.74016282225238,1474]},
{"key":[2008,2],"value":[43.73733719247467,1382]},
...

*/

parseDate = d3.time.format("%Y-%m").parse;
 
d3.json(jsonurl, function(error, jsondata) {

  if (error) { return error; }

   jsondata = jsondata.rows;

   jsondata.forEach(function (d) { 

     data0.push( [parseDate(d.key.join('-')), d.value[0], d.value[1] ] );

     data = data0.map(function(d) {
       return {
          date:  d[0],
          value: d[1],
          xlen:  d[2]
       };
     });
 });

// ##################################################################

var margin = {top: 20, right: 20, bottom: 70, left: 40},
    width = 800 - margin.left - margin.right,
    height = 400 - margin.top - margin.bottom;

var x = d3.scale.ordinal().rangeRoundBands([0, width], .05);

var y = d3.scale.linear().range([height, 0]);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom")
    .tickFormat(d3.time.format("%Y-%m"));

var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left")
    .ticks(10);

var svg = d3.select("body").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 + ")");
 
  x.domain(data.map(function(d) { return d.date; }));
  y.domain([0, d3.max(data, function(d) { return d.value + 5; })]);

  svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis)
    .selectAll("text")
      .style("text-anchor", "end")
      .attr("dx", "-.8em")
      .attr("dy", "-.55em")
      .attr("transform", "rotate(-90)" );

  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("PM 10");

  svg.selectAll("bar")
      .data(data)
      .enter()
      .append("rect")
      .attr("x", function(d) { return x(d.date); })
      .attr("width", x.rangeBand())
      .attr("y", function(d) { return y(d.value); })
      .attr("height", function(d) { return height - y(d.value); })

      .attr("fill", function(d) {
        return "rgb(0, 0, " + (Math.floor(d.value) * 10) + ")";
      })

      .on("mouseover", function() {
         d3.select(this)
           .attr("fill", "orange")
      })

      .on("mouseout", function(d) {
         d3.select(this)
           .transition()
           .duration(250)
           .attr("fill", "rgb(0, 0, " + (Math.floor(d.value) * 10) + ")")
      });

});

</script>

set_cors_cloudant.txt

# ok
curl -k -i -u USERNAME -X PUT https://USERNAME.cloudant.com/_api/v2/user/config/cors -H "Content-Type: application/json" -d '{"enable_cors":true,"allow_credentials":true,"allow_methods":["GET","PUT","POST","DELETE","OPTIONS"],"origins":["*"]}'

# 
https://github.com/cloudant-labs/cors-demo