Computing an Isochrone

You can calculate the coverage of a travel within given time limit.

Before you begin:
  • You need the CMO (City Analyst) role to be able to use this functionality.
  • At least one routing dataset must be available in your referential. For more information about creating routing datasets, see City Referential: Creating Prepared Datasets: Creating Routing Networks.
  1. From the Tools section of the action bar, click Compute Isochrone .
    Note: Isochrone calculation is displayed in the Temporary Items folder in the tree. Closing and reopening the Journey panel removes existing calculations (if any) in this folder.
  2. Either:
    • Click next to the first box, and then select the start point (point A) on the map.
    • Or, enter an address directly in the box to display a list of suggested addresses.
    The selected location is identified on the map and the address is displayed. If no address is available, coordinates are displayed instead. When you click a location symbol for an address, the corresponding coordinates are displayed in an additional tooltip. To hide the coordinates tooltip, click the location symbol again.

    Otherwise, hover over the location symbol to display the corresponding coordinates n a tooltip.

  3. Fill in the travel time, or use the arrows next to .

    For each travel time input, a new item is added to the tree view under the Isochrone node in the Temporary Items folder.

  4. Click next to the box below to define a travel time.

    Tip: To keep your isochrone items when you save the experience, move them from the Temporary Items folder to another permanent location. See Managing Temporary Items.

  5. Select the preferred transport mode.
    OptionDescription
    Public transport
    Car
    Bike
    Walk
  6. Click , and then define the appropriate options.
    OptionDescription
    Routing Dataset Lets you select the routing dataset on which you want to compute isochrones.
    Traffic Options

    Relevant only if you selected .

    		 Select a travel method for your journey:
    • Fastest calculates a fast journey that might include several transfers.
    • Minimum Transfer calculates a journey that might be longer, but with a minimum number of connections.

    You can choose between a combination of public transport. To do so, click the appropriate boxes:

    • Bus
    • Metro
    • Train
    • Tram
    • Funicular
    Time of Day Lets you specify your departure and arrival time.
    Speed Lets you specify the walk and bike speed.
  7. Optional: Use the Computation Type option to specify how polygons are displayed.

    By default, the option is activated. When the option is deactivated, resulting polygons overlap each other.

  8. Click Compute.
    Polygons are displayed on your map to show locations reachable from the start location in the specified time range.
    Computation Type is ON

    Computation Type is OFF

    The result is also displayed in the tree under the Isochrone Result node in the Temporary Items folder.

  9. In the Isochrone panel, modify your travel parameters.

    For example, select another preferred transport mode and change colors.

  10. Click Compute.
    The result is updated with the new parameters.

  11. Optional: In the Isochrone panel, click to add a new travel time to the calculation.

    Note: Click next to a limit to remove it from the calculation.

  12. Click Compute.
    The new limit is displayed.

  13. Optional: Select an isochrone item in the tree or in the experience, and then modify its representation attributes in the Properties panel.


  14. Optional: In the tree view, right-click the Isochrone node, and then select Export Drawing.

    This lets you download your results to GeoJSON format and tune data through a dedicated editor.

    A tab named "isochrone.geojson" is displayed at the bottom of the widget: select Show in folder to display the storage location on your local disk.

    For more information, see Exporting Drawings.

  15. To exit the command, click Compute Isochrone .