Object Modeling in ArcInfo 8 GIS in Water Resources Consortium February 23-25, 2000 Dale Honeycutt ESRI

Object Modeling in Object Modeling in ArcInfo 8ArcInfo 8

Object Modeling in Object Modeling in ArcInfo 8ArcInfo 8

GIS in Water Resources GIS in Water Resources ConsortiumConsortium

February 23-25, 2000February 23-25, 2000

Dale HoneycuttDale Honeycutt

ESRIESRI

TopicsTopicsTopicsTopics

• Whirlwind overview of ArcInfo 8Whirlwind overview of ArcInfo 8

• GeoDatabase overviewGeoDatabase overview

• Data modeling and data model Data modeling and data model extensionsextensions

• NetworkNetwork

Brief Overview of Brief Overview of ArcInfo 8ArcInfo 8

Brief Overview of Brief Overview of ArcInfo 8ArcInfo 8

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ArcInfo 8ArcInfo 8ArcInfo 8ArcInfo 8

Arc

ArcEdit

ArcPlot

Arc Catalog

Arc Map

Arc Toolbox

ServersServersArcStormArcStormArcSDEArcSDE

GIS AdminGIS AdminLicense ManagerLicense Manager

User SetupUser Setup

UN

IX &

Win

dow

s N

TW

ind

ows

NT

UNIX &Windows NT

Suggested readingSuggested readingSuggested readingSuggested reading

• Modeling our WorldModeling our World

• Building a GeodatabaseBuilding a Geodatabase

ArcInfo 8 ArchitectureArcInfo 8 ArchitectureArcInfo 8 ArchitectureArcInfo 8 Architecture

Arc CatalogArc Catalog Arc MapArc Map Arc ToolboxArc Toolbox

FilesFiles PersonalPersonalSDESDE

GeoObjectsGeoObjects

Arc SDEArc SDE

ArcInfo 8 Desktop FocusArcInfo 8 Desktop FocusArcInfo 8 Desktop FocusArcInfo 8 Desktop Focus

Arc CatalogArc Catalog Arc MapArc Map Arc ToolboxArc Toolbox

Arc/InfoArc/InfoToolsTools

Editing, AnalysisEditing, AnalysisMap DevelopmentMap Development

Spatial DataSpatial DataManagementManagement

• Browse data (Graphical or Browse data (Graphical or textual)textual)

ArcCatalogArcCatalogArcCatalogArcCatalog

• Manage dataManage data• Create Access databasesCreate Access databases• Define tables, add fieldsDefine tables, add fields

• Set object propertiesSet object properties• validation rulesvalidation rules• relationshipsrelationships• etc.etc.

• Set, view MetadataSet, view Metadata

Arc MapArc MapArc MapArc Map

• Perform map-based tasksPerform map-based tasks• MappingMapping• EditingEditing• QueriesQueries• AnalysisAnalysis• ChartingCharting• ReportingReporting

Editing in Arc MapEditing in Arc MapEditing in Arc MapEditing in Arc Map

• Display andDisplay andedit in theedit in thesamesameenvironmentenvironment

CoverageGeodatabase Shapefile

ArcToolboxArcToolboxArcToolboxArcToolbox

• GUI for ARC commandsGUI for ARC commands• ToolsTools• WizardsWizards

• Import/export Import/export GeoDatabasesGeoDatabases

• Arc server clientArc server client

GeoDatabase OverviewGeoDatabase OverviewGeoDatabase OverviewGeoDatabase Overview

GeoDatabaseGeoDatabaseGeoDatabaseGeoDatabase

• New format for storing spatial New format for storing spatial datadata

• Think of it as a new kind of Think of it as a new kind of coveragecoverage

• Features are seen as objects Features are seen as objects with behavior, stored in an with behavior, stored in an RDBMSRDBMS

MSAccess

Large - high performanceNeeds SDE

The Geodatabase is The Geodatabase is ScaleableScaleable

The Geodatabase is The Geodatabase is ScaleableScaleable

Oracle,Informix,Sybase

SQL Server

Fittings

Valves

Main Lines

Fire Hydrants

Water Layers

GIS data is organized GIS data is organized into layersinto layers

GIS data is organized GIS data is organized into layersinto layers

CoveragesCoveragesCoveragesCoverages

• Each layer stored in a separate Each layer stored in a separate coveragecoverage

• Coverages based on planar Coverages based on planar graph topologygraph topology

Coverages –behaviorCoverages –behaviorCoverages –behaviorCoverages –behavior

• With coverages, behavior based on With coverages, behavior based on topologytopology• Very powerful, but limiting…Very powerful, but limiting…

• An arc is both a river and a state boundary – An arc is both a river and a state boundary – they have the same behaviorthey have the same behavior

• But… move a powerpole (a point), the But… move a powerpole (a point), the powerline (an arc) does not movepowerline (an arc) does not move

• Behavior encapsulated in the Behavior encapsulated in the application application • I.e., AML, ODEI.e., AML, ODE• All users must use the same applicationAll users must use the same application

GeoDatabaseGeoDatabaseGeoDatabaseGeoDatabase

• Layers are organized in a single Layers are organized in a single file (Access) or enterprise file (Access) or enterprise databasedatabase

• Features in layers can have user-Features in layers can have user-defined behaviordefined behavior• Majority of behavior provided – Majority of behavior provided –

very little customization neededvery little customization needed

• No external application neededNo external application needed

Data Organized in a

Single GeoDatabase

Instance

Geodatabase organizationGeodatabase organizationGeodatabase organizationGeodatabase organization

GeoDatabase features GeoDatabase features are objectsare objects

GeoDatabase features GeoDatabase features are objectsare objects

• Example: powerpole object with Example: powerpole object with properties and behavior versus a properties and behavior versus a point with some attributespoint with some attributes

• Users can define objects, their Users can define objects, their relationships, and their behavior relationships, and their behavior with ArcCatalog and with CASE with ArcCatalog and with CASE toolstools

ObjectObject == IdentityIdentity StateState++ BehaviorBehavior++

Basic Object StuffBasic Object StuffBasic Object StuffBasic Object Stuff

IdentityIdentityObjectObject == StateState BehaviorBehavior++ ++

Must Have

Provides a way to Provides a way to distinguish an object distinguish an object

from othersfrom others

IdentityIdentity

Unique Name

IdentityIdentityIdentityIdentity

ObjectObject == IdentityIdentity StateState BehaviorBehavior++ ++

Must HaveMust Have May HaveMay Have

All of information or All of information or data of an object at a data of an object at a

given timegiven time

AttributesAttributes

StateState

StateStateStateState

ObjectObject == IdentityIdentity StateState BehaviorBehavior++ ++

All of the abilities of an All of the abilities of an objectobject

Describe the actions and Describe the actions and reactions of the objectreactions of the object

Behavior

Must HaveMust Have May HaveMay Have May HaveMay Have

Methods Methods (Operations) (Operations)

BehaviorBehaviorBehaviorBehavior

Representing objectsRepresenting objectsRepresenting objectsRepresenting objects

ObjectObject == IdentityIdentity StateState++ BehaviorBehavior++

MeterMeter NameNameaccountNumberaccountNumberaccountTypeaccountTypeaccountAddressaccountAddressserialNumberserialNumbermanfacturemanfacturemodelmodelsizesizeserialNumberserialNumber

AttributesAttributes

isActive()isActive()computeUse()computeUse() MethodsMethods

Must HaveMust Have May HaveMay Have May HaveMay Have

Spatial Data ModelsSpatial Data ModelsSpatial Data ModelsSpatial Data Models

• A A spatial data modelspatial data model is a data is a data structure with methodsstructure with methods• Vector geometry, network graph, Vector geometry, network graph,

raster, TIN, planar graphraster, TIN, planar graph

• All spatial data models filter All spatial data models filter information on a mapinformation on a map

• The map is the penultimate data The map is the penultimate data modelmodel

Spatial Data ModelsSpatial Data ModelsSpatial Data ModelsSpatial Data Models

• GeoDatabase is a FRAMEWORK for GeoDatabase is a FRAMEWORK for exposing the vector data model and exposing the vector data model and the network data model as extensible the network data model as extensible objectsobjects

• Rasters and TINs are currently Rasters and TINs are currently served “holistically”served “holistically”• Operations on the whole data structure Operations on the whole data structure

(raster: “create drainage basins” as (raster: “create drainage basins” as opposed to individual cellsopposed to individual cells

FrameworkFrameworkFrameworkFramework

A framework is a set of A framework is a set of cooperating classes that make cooperating classes that make up a reusable design for a up a reusable design for a specific class of software... specific class of software...

Framework…Framework…Framework…Framework…

• When you use a toolkit (or When you use a toolkit (or conventional subroutine library), you conventional subroutine library), you write the main body of the write the main body of the application and call the code that you application and call the code that you want to reuse. want to reuse.

• When you use a framework, you When you use a framework, you reuse the main body and write the reuse the main body and write the code it calls. code it calls.

Framework…Framework…Framework…Framework…

• You customize a framework by creating You customize a framework by creating application specific sub-classes of abstract application specific sub-classes of abstract classes from the framework.classes from the framework.

• Not only can you build applications faster as Not only can you build applications faster as a result, but the applications have similar a result, but the applications have similar structures. They are easier to maintain, and structures. They are easier to maintain, and they seem more consistent to their users. they seem more consistent to their users.

• On the other hand, you lose some creative On the other hand, you lose some creative freedom, since many design decisions have freedom, since many design decisions have been made for you.been made for you.

GeoDatabase FrameworkGeoDatabase FrameworkGeoDatabase FrameworkGeoDatabase Framework

Object ClassesObject ClassesObject ClassesObject Classes

Feature ClassesFeature ClassesFeature ClassesFeature Classes

Network Feature Network Feature ClassesClasses


RelationshipsRelationshipsRelationshipsRelationships

SubtypesSubtypesSubtypesSubtypes

Attribute Attribute DomainsDomainsAttribute Attribute DomainsDomains

Connectivity Connectivity RulesRules


Core Core

ObjectsObjects

Core Core

ObjectsObjects BehaviorBehaviorBehaviorBehavior

InheritanceInheritanceInheritanceInheritance

Data Data

ModelingModeling

Data Data

ModelingModeling

Merge/Split Merge/Split RulesRules


Core Objects -ObjectCore Objects -ObjectCore Objects -ObjectCore Objects -Object

• Rows in a databaseRows in a database• Have unique ID Have unique ID

assigned by the assigned by the GeodatabaseGeodatabase

• Non-spatialNon-spatial





Core Objects -ObjectCore Objects -ObjectCore Objects -ObjectCore Objects -Object

• Objects with Objects with geometry (shape)geometry (shape)

• Points, Lines, Points, Lines, PolygonsPolygons





Core Objects - NetworkCore Objects - NetworkCore Objects - NetworkCore Objects - Network

• Provide network Provide network connectivity between connectivity between feature classesfeature classes

• A “kind of” featureA “kind of” feature

• Much more on Much more on networks later!networks later!





Simple junctionsSimple junctions

Simple edgesSimple edges

Complex junctionsComplex junctions

Complex edgesComplex edges

Data Modeling - Data Modeling - InheritanceInheritance


• Objects and Objects and features can inherit features can inherit behaviorbehavior• A “reach” is a kind A “reach” is a kind

of “flow line” which of “flow line” which is a kind of “network is a kind of “network edge”edge”








InheritanceInheritanceInheritanceInheritance ESRIClasses:: ComplexEdgeFeature

-Com_id : esriFieldTypeInteger-Rch_code : esriFieldTypeInteger-Rch_date : esriFieldTypeString-Level : esriFieldTypeInteger-Meters : esriFieldTypeDouble-Gnis_id : esriFieldTypeString-Name : esriFieldTypeString-Wshd_code :esriFieldTypeInteger

Reach

-ArcHydroID : esriFieldTypeInteger-Wshed_ID : esriFieldTypeInteger-Wbody_ID : esriFieldTypeInteger

FlowLine

Data Modeling - Data Modeling - RelationshipsRelationships


• Peer-to-peerPeer-to-peer

• CompositeComposite

• 1:1, 1:m, m:1, m:m1:1, 1:m, m:1, m:mRelationshipsRelationshipsRelationshipsRelationships





+OBJECTID : esriFieldTypeOID

ESRI Classes::Object

+Shape : esriFieldTypeGeometry

ESRI Classes::Feature

-ParcelValue : esriFieldTypeInteger-CombinedBuildingValue : esriFieldTypeInteger

Parcel-Stories : esriFieldTypeInteger-Height : esriFieldTypeInteger-BuildingValue : esriFieldTypeInteger-ParcelID : esriFieldTypeInteger

Building

Contains






• An association between objectsAn association between objects

• Can trigger behavior (cascade delete, Can trigger behavior (cascade delete, move to follow, custom…)move to follow, custom…)

Class1 Class2

• Related objects can message each otherRelated objects can message each other

Class1 Class2

Origin to destination

Destination to origin

Both directions

Class1

method1()

Class2

method2()

Method1() in Class1 uses the relationship to Class2 to find and start method2()



CompositeComposite(lifetime control)(lifetime control)

Class1 Class2

AssociationAssociation(peer to peer)(peer to peer)

1..*1..***Class1 Class2

Many to 1 or MoreMany to 1 or More

• Objects exist independent Objects exist independent of each otherof each other

• An association (UML An association (UML terminology)terminology)

• Destination object can’t Destination object can’t exist without origin featuresexist without origin features

• Destination features move Destination features move with origin featureswith origin features

Data Modeling - Data Modeling - SubtypesSubtypes

Data Modeling - Data Modeling - SubtypesSubtypes

• Allows an attribute Allows an attribute determine behavior determine behavior of other attributesof other attributes

• Example: water Example: water transmission vs. transmission vs. distribution pipes distribution pipes have different have different allowable PSI and allowable PSI and pipe diameterspipe diameters




Behavior – Attribute Behavior – Attribute DomainsDomains

Behavior – Attribute Behavior – Attribute DomainsDomains

• Describe the legal Describe the legal values of a field typevalues of a field type

• Used to ensure attribute Used to ensure attribute

integrityintegrity

• Can be shared among Can be shared among object and feature object and feature classesclasses

• Types of domainsTypes of domains• RangeRange• Coded valueCoded value






Behavior – Connectivity Behavior – Connectivity RulesRules


+FieldType : <unspecified> = esriFieldTypeInteger+MergePolicy : <unspecified> = esriMPTDefaultValue+SplitPolicy : <unspecified> = esriSPTDefaultValue+Code1 : <unspecified> = 1+Code2 : <unspecified> = 2+Code3 : <unspecified> = 3

«CodedValueDomain»TemplateCodedValueDomain

+FieldType : <unspecified> = esriFieldTypeInteger+MergePolicy : <unspecified> = esriMPTDefaultValue+SplitPolicy : <unspecified> = esriSPTDefaultValue+MinValue : <unspecified> = 1+MaxValue : <unspecified> = 100

«RangeDomain»TemplateRangeDomain






Behavior - Connectivity Behavior - Connectivity RulesRules

Behavior - Connectivity Behavior - Connectivity RulesRules

• Help you maintain a Help you maintain a valid networkvalid network

• Connectivity rules Connectivity rules include:include:• Edge-junction rulesEdge-junction rules

• cardinalitycardinality

• Edge-edge rulesEdge-edge rules• permissible junction permissible junction

typestypes• default junction typedefault junction type






ConnRule



• Edge connectivity rulesEdge connectivity rules• n-ary associationn-ary association

• Junction connectivity rulesJunction connectivity rules

EdgeST1 EdgeST2

JunctionST3

JunctionST3 EdgeST1ConnRule

JunctionST1

Default

Behavior - Merge/Split Behavior - Merge/Split RulesRules

Behavior - Merge/Split Behavior - Merge/Split RulesRules






Behavior -ValidationBehavior -ValidationBehavior -ValidationBehavior -Validation

• Attribute domains and Attribute domains and Connectivity rules are used to Connectivity rules are used to validate features during data validate features during data entry and editing.entry and editing.

MetadataMetadataMetadataMetadata

• Everything in a GeoDatabase can Everything in a GeoDatabase can have Metadatahave Metadata

• Stored as XML, viewed and Stored as XML, viewed and edited in ArcCatalogedited in ArcCatalog

• Easily extensibleEasily extensible

Data ModelingData ModelingData ModelingData Modeling

Data Modeling MechanicsData Modeling MechanicsData Modeling MechanicsData Modeling Mechanics

Code Generation

Code Generation

MSRepository

SchemaCreationSchemaCreation

3rd Party CASE Tool

UML Object Model

Building

LandBase.DLL

GeoDatabase

Building FClass

ChemicalInjectorAerator Motor

AveragePowerUsagePeakPowerUsagePhasesRatedPowerRPMVariableSpeedVoltage

Object

*

Valve

DiameterJointType

SamplingStationInterconnectPoint Hydrant

StationIDProviderRecipientSource

Meter

DiameterFlowRangeMeasurementDate

ScadaSensor

CurrentValueIDMeasurementType

LineProtector

Casing Anode

*

IndividualTrayAreaRiserCountTotalTrayAreaTrayCount

SluiceGate

CurrentElevationHeightNormalElevationWidth

ChemicalType

MeasurementTypes are Amperage,ChlorineResidual,ChlorineTankWeight, Depth,DischargePressure, Elevation, Flow,Pressure, SuctionPressure,TankLevel, Temperature, Turbidity,Velocity, Voltage, and WellLevel.

UndergroundEnclosure

CoverMaterialCoverTypeDepthFrameMaterialFrameTypeInvertElevationMeasurement[2]

1..* 1..*

SurgeReliefTank

PressureSettingCapacity

Types include Anchor,Blocking, Deadman, andKicker.

StandByPower

PhasesVoltageAmperage

Types are Casement,ConduitBridge,ProtectiveTunnel,AccessTunnel.

DiameterMaterialRecordedLength

ThrustProtection

AirGap

GapMeasureOutletDiameter

WarehouseEquipment

WarehouseHydrant

BarrelDiameterMainValveTypeNozzelDiameter[4]OutletConfigurationSeatDiameter

WarehouseMeter

FlowRangeDiameter

WarehouseValve

Diameter

WarehouseSystemValve

BypassValveClockwiseToCloseMotorizedTurnsToClose

Types include Ball, Butterfly,Cone, Gate, and Plug.RegulationTypes are Flowand Pressure.

WarehouseControlValve

Types are Air, AirRelease,Combination, Vacuum, andVacuumRelease.

BarrelDiameterMainValveTypeNozzelDiameter[4]OutletConfigurationSeatDiameter

WarehouseHydrant

0..1

SystemValve

BypassValveClockwiseToCloseCurrentlyOpenMotorizedNormallyOpenPercentOpenPressureSettingRegulationTypeTurnsToClose

ControlValve

WarehouseSystemValve

0..1

WarehouseControlValve

0..1

LateralPoint

AccountIDCriticalCustomerDiameterLocationDescriptionMaterial

AnalysisPoint

RecordIDRecordedValueType

Fitting

JoiningMethodMaterialSize[4]

Types include Bend, Cap,Cross, Coupling,ExpansionJoint, Offset,Reducer, Riser, Saddle,Sleeve, Tap, Tee, Weld,and Wye.

SpatialOperationsRecord

DateID

OperationsRecord

DateIDLocationDescriptionType

WarehouseIDWarehouseStatusWarrantyDate

ClearWell

CapacityDepthOperatingRangeStationIDWidth[2]

WarehouseMeter

0..1

Types include Leak,Maintenance, Repair,and Inspection.

CountMaterialWeight

ArcFMFacility

SimpleJunctionFeature

AdministrativeAreaFacilityIDInstallDateLocationDetailOperationalAreaRotationStatusTypeWorkorderID

ArcFMFeature

Feature

WaterFeature

ElevationLocationDescriptionWaterType

AdministrativeAreaFacilityIDInstallDateOperationalAreaStatusTypeWorkorderID

NetworkStructure

NameOperationalDateReferenceIDSourceUsage

WaterFacility

ElevationWaterType

ArcFMEquipment

EquipmentIDInstallDateManufacturerModelSerialNumberStatusType

Types areAirControl,Altitude, andBackflowControl

Manhole

AccessTypeGroundTypeHighPipeElevationInteriorDropInvertElevationAccessDiameterRimElevationWallMaterial

Types areEnclosedStorageFacility,ProductionWell, PumpStation,StorageBasin, TreatmentPlant.

MainLine

PressurizedMain GravityMain

BarrelCountCrossSectionShapeDownstreamInvertMeasurement[2]NominalSizeSlopeUpstreamInvert

DepthDiameterGroundSurfaceTypePressureRating

LateralLine

LocationDescriptionSize

0..1

ExteriorCoatingJointType[2]LiningTypePipeClassRoughness

Types include BlowOff, Bypass,AirRelease, ChemicalInjection,DistributionMain, Interconnect,PipeBridge, SamplingStation,and TransmissionMain.

Types include: Domestic,Fire, Combination,Commercial, Irrigation,IndustrialServices, andHydrant laterals.

WaterTypes areCombinedWastewater,PotableWater, RawWater,ReclaimedWater, SaltWater,Sewage, StormRunoff, andWastewaterEffluent.

Types are Carrier,InlineStorage, andTransportPipe.

AdministrativeAreaFacilityIDInstallDateMaterialOperationalAreaStatusTypeWorkorderID

ComplexEdgeFeature

ArcFMLine

FlowMeasurementIDWaterType

WaterLine

Types are MeterBox,ValveVault, and Vault.

WaterStructure

OperationalDateStatus

Water DistributionObject Model

Analysis Model

ArcFM Water 8ESRI Confidential

8.0.1 Release

NOTE: Most relationships will be specified in thedetailed-design UML model. Accessors and mutatorsare implicit in the design.

Color Key

Lines

Facilities and Structures

Equipment

Features

Pump

InletSizeDischargeSizeType

Types include AxialFlow,Centrifugal, Jet, Reciprocating,Rotary, Screw, and Turbine.

WHPump

0..1

Types include AxialFlow,Centrifugal, Jet,

Reciprocating, Rotary,Screw, and Turbine.

WarehousePump

InletSizeDischargeSizeRatedFlowRatedPressureTotalDynamicHeadType

Types areEnclosedStorageFacility,ProductionWell, PumpStation,StorageBasin, TreatmentPlant.

Example UML Example UML ModelModel

Example UML Example UML ModelModel

Data ModelingData ModelingData ModelingData Modeling

• Time spent data modeling is very Time spent data modeling is very beneficial in the long runbeneficial in the long run

• Use ArcCatalog for tactical control of Use ArcCatalog for tactical control of simpler systemssimpler systems

• Use CASE (UML and schema wizard) Use CASE (UML and schema wizard) for modeling complex systemsfor modeling complex systems

• Both tools will simplify your lifeBoth tools will simplify your life

Data Model ExtensionData Model ExtensionData Model ExtensionData Model Extension

• A documented data model (Visio A documented data model (Visio UML) for a domain (water UML) for a domain (water resources)resources)

• A book explaining the modelA book explaining the model

• A data dictionary for salient A data dictionary for salient propertiesproperties


• Ideally created and supported by Ideally created and supported by a group of stakeholdersa group of stakeholders• Such as this groupSuch as this group

A Data Model Extension A Data Model Extension is NOTis NOT

A Data Model Extension A Data Model Extension is NOTis NOT

• An applicationAn application• It plugs into the Geodatabase It plugs into the Geodatabase

frameworkframework

• ProprietaryProprietary• Whoever can buy the bookWhoever can buy the book


• Provides a published standard Provides a published standard so that domain-specific software so that domain-specific software can be developed with can be developed with confidenceconfidence• OpenOpen

• For feeFor fee


• Remember – “any dang fool can get Remember – “any dang fool can get complicated, it takes a genius to be complicated, it takes a genius to be simple” simple” • Keep your models simple and to the Keep your models simple and to the

pointpoint

• Largely a fence building exerciseLargely a fence building exercise• Deciding what to model is more Deciding what to model is more

important then how to modelimportant then how to model


• Continuum between general Continuum between general interest and application specific interest and application specific refinementsrefinements

Water Resources ModelWater Resources ModelWater Resources ModelWater Resources Model

High-level systemsHigh-level systemsWatershedsWatersheds

ChannelsChannels

X-sectionsX-sections

Temporal ObservationsTemporal Observations

Modeling Linear Modeling Linear FeaturesFeatures




• Linear ReferencingLinear Referencing• Using river mile systemsUsing river mile systems

• NetworksNetworks• !!!!!!!!

Linear ReferencingLinear ReferencingLinear ReferencingLinear Referencing

• All coordinates have <X,Y>All coordinates have <X,Y>• Optionally a Measure <M> and an Optionally a Measure <M> and an

Elevation <Z>Elevation <Z>• A linear feature that has A linear feature that has

Measures and an identifier is Measures and an identifier is referred to as a ROUTE (a reach referred to as a ROUTE (a reach in hydro terms)in hydro terms)


• EVENTS are EVENTS are objects that objects that contain linear contain linear referencesreferences

• Events are Events are points or linespoints or lines

• Lots of hydro Lots of hydro applications – applications – river reachriver reach

EventsEventsEventsEvents

• Events can be objects (linear Events can be objects (linear reference only) or features reference only) or features (calculate and store the shape)(calculate and store the shape)

• When displaying objects with a When displaying objects with a linear reference, the shape is linear reference, the shape is dynamically computed (hence dynamically computed (hence “Dynamic Segmentation”)“Dynamic Segmentation”)


• Host of methods to create routes and Host of methods to create routes and CALIBRATE their measuresCALIBRATE their measures• The only restriction is that measures are The only restriction is that measures are

real numbersreal numbers• Linear interpolation between measuresLinear interpolation between measures

• Host of methods to display EVENTSHost of methods to display EVENTS

NetworksNetworksNetworksNetworks

Documents

Object Modeling in ArcInfo 8 GIS in Water Resources Consortium February 23-25, 2000 Dale Honeycutt ESRI