Sankey Diagrams in JavaScript

How to make D3.js-based sankey diagrams in Plotly.js.


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var data = {
  type: "sankey",
  orientation: "h",
  node: {
    pad: 15,
    thickness: 30,
    line: {
      color: "black",
      width: 0.5
    },
   label: ["A1", "A2", "B1", "B2", "C1", "C2"],
   color: ["blue", "blue", "blue", "blue", "blue", "blue"]
      },

  link: {
    source: [0,1,0,2,3,3],
    target: [2,3,3,4,4,5],
    value:  [8,4,2,8,4,2]
  }
}

var data = [data]

var layout = {
  title: {
    text: "Basic Sankey"
  },
  font: {
    size: 10
  }
}

Plotly.react('myDiv', data, layout)
Click to copy
A1A2B1B2C1C2
Basic Sankey
var data = {
  type: "sankey",
  domain: {
    x: [0,1],
    y: [0,1]
  },
  orientation: "h",
  valueformat: ".0f",
  valuesuffix: "TWh"
}

var data = [data]

var layout = {
  title: {
    text: "Energy forecast for 2050<br>Source: Department of Energy & Climate Change, Tom Counsell via <a href='https://bost.ocks.org/mike/sankey/'>Mike Bostock</a>"
  },
  width: 1118,
  height: 772,
  font: {
    size: 10
  }
}
Click to copy
d3.json('https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json', function(fig){

var data = {
  type: "sankey",
  domain: {
    x: [0,1],
    y: [0,1]
  },
  orientation: "h",
  valueformat: ".0f",
  valuesuffix: "TWh",

  node: {
    pad: 15,
    thickness: 15,
    line: {
      color: "black",
      width: 0.5
    },
   label: fig.data[0].node.label,
   color: fig.data[0].node.color
      }
}

var data = [data]

var layout = {
  title: {
    text: "Energy forecast for 2050<br>Source: Department of Energy & Climate Change, Tom Counsell via <a href='https://bost.ocks.org/mike/sankey/'>Mike Bostock</a>"
  },
  width: 1118,
  height: 772,
  font: {
    size: 10
  }
}

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

});
Click to copy
Energy forecast for 2050Source: Department of Energy & Climate Change, Tom Counsell via Mike Bostock
d3.json('https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json', function(fig){

var data = {
  type: "sankey",
  domain: {
    x: [0,1],
    y: [0,1]
  },
  orientation: "h",
  valueformat: ".0f",
  valuesuffix: "TWh",
  node: {
    pad: 15,
    thickness: 15,
    line: {
      color: "black",
      width: 0.5
    },
   label: fig.data[0].node.label,
   color: fig.data[0].node.color
      },

  link: {
    source: fig.data[0].link.source,
    target: fig.data[0].link.target,
    value: fig.data[0].link.value,
    label: fig.data[0].link.label
  }
}

var data = [data]

var layout = {
  title: {
    text: "Energy forecast for 2050<br>Source: Department of Energy & Climate Change, Tom Counsell via <a href='https://bost.ocks.org/mike/sankey/'>Mike Bostock</a>"
  },
  width: 1118,
  height: 772,
  font: {
    size: 10
  }
}

Plotly.newPlot('myDiv', data, layout)
});
Click to copy
Agricultural 'waste'Bio-conversionLiquidLossesSolidGasBiofuel importsBiomass importsCoal importsCoalCoal reservesDistrict heatingIndustryHeating and cooling - commercialHeating and cooling - homesElectricity gridOver generation / exportsH2 conversionRoad transportAgricultureRail transportLighting & appliances - commercialLighting & appliances - homesGas importsNgasGas reservesThermal generationGeothermalH2HydroInternational shippingDomestic aviationInternational aviationNational navigationMarine algaeNuclearOil importsOilOil reservesOther wastePumped heatSolar PVSolar ThermalSolarTidalUK land based bioenergyWaveWind
Energy forecast for 2050Source: Department of Energy & Climate Change, Tom Counsell via Mike Bostock
d3.json('https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy_dark.json', function(fig){

var data = {
  type: "sankey",
  domain: {
    x: [0,1],
    y: [0,1]
  },
  orientation: "h",
  valueformat: ".0f",
  valuesuffix: "TWh",
  node: {
    pad: 15,
    thickness: 15,
    line: {
      color: "black",
      width: 0.5
    },
   label: fig.data[0].node.label,
   color: fig.data[0].node.color
      },
  link: {
    source: fig.data[0].link.source,
    target: fig.data[0].link.target,
    value: fig.data[0].link.value,
    label: fig.data[0].link.label
  }
}

var data = [data]

var layout = {
  title: {
    text: "Energy forecast for 2050<br>Source: Department of Energy & Climate Change, Tom Counsell via <a href='https://bost.ocks.org/mike/sankey/'>Mike Bostock</a>"
  },
  width: 1118,
  height: 772,
  font: {
    size: 10,
    color: 'white'
  },
  plot_bgcolor: 'black',
  paper_bgcolor: 'black'
}

Plotly.newPlot('myDiv', data, layout)
});
Click to copy
Agricultural 'waste'Bio-conversionLiquidLossesSolidGasBiofuel importsBiomass importsCoal importsCoalCoal reservesDistrict heatingIndustryHeating and cooling - commercialHeating and cooling - homesElectricity gridOver generation / exportsH2 conversionRoad transportAgricultureRail transportLighting & appliances - commercialLighting & appliances - homesGas importsNgasGas reservesThermal generationGeothermalH2HydroInternational shippingDomestic aviationInternational aviationNational navigationMarine algaeNuclearOil importsOilOil reservesOther wastePumped heatSolar PVSolar ThermalSolarTidalUK land based bioenergyWaveWind
Energy forecast for 2050Source: Department of Energy & Climate Change, Tom Counsell via Mike Bostock

The following example sets node.x and node.y to place nodes in the specified locations, except in the snap arrangement (default behaviour when node.x and node.y are not defined) to avoid overlapping of the nodes, therefore, an automatic snapping of elements will be set to define the padding between nodes via nodepad. The other possible arrangements are: 1) perpendicular 2) freeform 3) fixed

var data = [{
  type: "sankey",
    arrangement: "snap",
    node:{
        label: ["A", "B", "C", "D", "E", "F"],
        x: [0.2, 0.1, 0.5, 0.7, 0.3, 0.5],
        y: [0.7, 0.5, 0.2, 0.4, 0.2, 0.3],
        pad:10}, // 10 Pixels
    link: {
        source: [0, 0, 1, 2, 5, 4, 3, 5],
        target: [5, 3, 4, 3, 0, 2, 2, 3],
        value: [1, 2, 1, 1, 1, 1, 1, 2]}
    }]

var layout = {"title": "Sankey with manually positioned node"}

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


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You can set the alignment of nodes using node.align. In this example, we align nodes to the "right". node.align can also be set to "left", "center", or "justify". The default is "justify" if `node.align is not set, and is similar to aligning to the "left", except that nodes without outgoing links are moved to the right of the figure.

var data = {
  type: "sankey",
  orientation: "h",
  node: {
    label: ["0", "1", "2", "3", "4", "5"],
    align: "right",
  },

  link: {
    source: [0, 1, 4, 2, 1],
    target: [1, 4, 5, 4, 3],
    value: [4, 2, 3, 1, 2],
  },
};

var data = [data];

var layout = {
  title: {
    text: "Align Nodes (Right)"
  },
  font: {
    size: 10,
  },
};

Plotly.newPlot('myDiv', data, layout);
Click to copy
012345
Align Nodes (Right)