Nodes

The Nodes dataframe type specifies information about single locations (nodes or vertices). The initDataframe() function may be used to create a blank/empty Nodes dataframe. This dataframe may also be populated from a list of lat/lon coordinates, using the createNodesFromLocs() function. The generateNodes() function may be used to populate a Nodes dataframe with nodes generated from a distribution (e.g., uniformly distributed over a region, or normally distributed about a central location).

The table below describes each of the fields/columns of a Nodes dataframe:

Field Name	Data Type	Description
id	int	Unique identifier for each row of the dataframe.
lat	float	Latitude of the node, in [degrees]. 0-degrees latitude is the equator. Negative latitudes are south of the equator; positive latitudes are north. The range is from -90 to +90.
lon	float	Longitude of the node, in [degrees]. 0-degrees longitude is Greenwich, England. Negative longitudes are west of Greenwich; positive longitudes are east. The range is from -180 to +180.
altMeters	float	Altitude of this node, in units of [meters above ground level] (AGL).
nodeType	string	A text string that may be used to categorize/classify a collection of nodes. This field is not used by VeRoViz explicitly. Examples could include “depots” or “customers”.
nodeName	string	A unique name for a particular node, such as “depot 1” or “customer 32”. The nodeName is not used by VeRoViz explicitly.
popupText	string	Text (or HTML) that will be displayed when a user clicks on the arc in Leaflet or Cesium.
leafletIconPrefix	string	There are a large number of Leaflet icons available. The IconPrefix identifies one of three collections: “glyphicon”, “fa”, or “custom”. See Leaflet Style for more details.
leafletIconType	string	The specific icon depends on the leafletIconPrefix. See Leaflet Style for the options for different prefixes.
leafletColor	string	Color of the node marker when displayed in Leaflet. See Leaflet Style for options of colors.
leafletIconText	string	The text shown in the marker when displayed in Leaflet. See Leaflet Style for more details.
cesiumIconType	string	Describes the icon used to denote a node when displayed in Cesium. See Cesium Style for options.
cesiumColor	string	Color of the node marker when displayed in Cesium. See Cesium Style for color options.
cesiumIconText	string	The text shown in the marker when displayed in Cesium. See Cesium Style for more details.
elevMeters	float	The elevation of the given [lat, lon] location, in units of [meters above mean sea level] (MSL).

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A Nodes dataframe can be used in several functions. Here is a list of whether the field is required/optional/ignored in different functions.

Note

Some explaination about “Required”, “Optional”, “Ignored”:

• “Required” means the function needs info from that field/column. That info can not be overridden by the function that uses the dataframe.

• “Optional” means the function will use the info from that field/column as a default value. However, some functions allow the user to temporarily “override” the optional values in the dataframe with different values provided in the function call.

• “Ignored” means the function neither needs nor uses info from that field/column.

In snapNodesToRoad()

Field Name	Required	Optional	Ignored
id			✓
lat	✓
lon	✓
altMeters			✓
nodeName			✓
nodeType			✓
popupText			✓
leafletIconPrefix			✓
leafletIconType			✓
leafletColor			✓
leafletIconText			✓
cesiumIconType			✓
cesiumColor			✓
cesiumIconText			✓
elevMeters			✓

In createCesium()

Field Name	Required	Optional	Ignored
id	✓
lat	✓
lon	✓
altMeters	✓
nodeName	✓
nodeType			✓
popupText	✓
leafletIconPrefix			✓
leafletIconType			✓
leafletColor			✓
leafletIconText			✓
cesiumIconType		✓
cesiumColor		✓
cesiumIconText		✓
elevMeters			✓

In createLeaflet()

Field Name	Required	Optional	Ignored
id	✓
lat	✓
lon	✓
altMeters			✓
nodeName		✓
nodeType			✓
popupText	✓
leafletIconPrefix		✓
leafletIconType		✓
leafletColor		✓
leafletIconText		✓
cesiumIconType			✓
cesiumColor			✓
cesiumIconText			✓
elevMeters			✓

In getTimeDist2D()

Field Name	Required	Optional	Ignored
id	✓
lat	✓
lon	✓
altMeters			✓
nodeName			✓
nodeType			✓
popupText			✓
leafletIconPrefix			✓
leafletIconType			✓
leafletColor			✓
leafletIconText			✓
cesiumIconType			✓
cesiumColor			✓
cesiumIconText			✓
elevMeters			✓

In getTimeDist3D()

Field Name	Required	Optional	Ignored
id	✓
lat	✓
lon	✓
altMeters	✓
nodeName			✓
nodeType			✓
popupText			✓
leafletIconPrefix			✓
leafletIconType			✓
leafletColor			✓
leafletIconText			✓
cesiumIconType			✓
cesiumColor			✓
cesiumIconText			✓
elevMeters			✓