gistfile1.js

var step = maxima[column] / 5;

    var styles = [];
    for (var i = 0; i <= 4; i++) {
      styles.push({
        where: "'" + column + "' >= " + (step * i) + " AND '" + column + "' < " + (step * (i + 1)),
        polygonOptions: {
  	      fillOpacity: 0.4,
          fillColor: colors[i]
        }
      });
    }
    return styles;
  }