## com.esri.arcgis.geometry Interface IEllipticArc

All Superinterfaces:
ICurve, IGeometry, Serializable
All Known Implementing Classes:
EllipticArc

`public interface IEllipticArcextends ICurve, Serializable`

#### Description

An Elliptic Arc is an object that describes any portion of an ellipse. The Major axis of the Elliptic Arc is the largest axis spanning between points on opposite sides of the ellipse. The Minor axis is the perpendicular bisector of the Major axis. Together, the Major and Minor axes determine the full ellipse on which the Elliptic Arc is generated. These parameters may also be specified in terms of the semi-Major axis (half of the Major axis) and the MinorMajorRatio (the ratio of the Minor axis to the Major axis). The ellipse may also be rotated. Rotation is described by the Rotation Angle. However, the effect of the Rotation Angle depends on the value of EllipseStd. If EllipseStd is TRUE, all angles and axes are calculated with respect to the Major Axis as though the Major Axis was at 0 radians. Also, the location of the From Point and To Point are given relative to the Center Point as though it is the origin. If EllipseStd is FALSE, all angles are caluclated in standard Cartesian coordinates. The portion of the complete ellipse represented by the Elliptic Arc is determined by the From Angle and Central Angle, both measured in radians.

#### Remarks

A CircularArc is a special case of an EllipticArc where the MinorMajorRatio is 1 (however, a CircularArc is NOT an EllipticArc).

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

`IPoint`, `IGeometry`, `IEnvelope`, `IConstructEllipticArc`, `ISegment`

Method Summary
` void` `complement()`
Changes this ellipse into its complement; 'from' and 'to' points are unchanged.
` void` ```getAxes(double[] semiMajor, double[] semiMinor, double[] minorMajorRatio)```
Gets the semi-major and semi-minor axes.
` IPoint` `getCenterPoint()`
The center point of the arc.
` double` `getCentralAngle()`
The included (or central) angle.
` double` `getFromAngle(boolean ellipseStd)`
The start angle (measured from a horizontal line through the center point) defining where the arc starts.
` double` `getToAngle(boolean ellipseStd)`
The end angle (measured from a horizontal line through the center point) defining where the arc ends.
` boolean` `isCircular()`
Indicates if this elliptical arc is acutally circular (major and minor axes same length).
` boolean` `isCounterClockwise()`
Indicates if this elliptic arc is oriented counter-clockwise from its 'from' point to its 'to' point.
` boolean` `isLine()`
Indicates if the arc is degenerated to a line.
` boolean` `isMinor()`
Indicates whether the arc is a minor arc or a major arc.
` boolean` `isPoint()`
Indicates if the arc is degenerated to a point.
` void` ```putAxes(double semiMajor, double minorMajorRatio)```
Sets the semi-major and semi-minor axes.
` void` ```putCoords(boolean ellipseStd, IPoint center, IPoint from, IPoint to, double rotationAngle, double minorMajorRatio, int orientation)```
Sets the center point and endpoints, angle of rotation, and orientation.
` void` ```putCoordsByAngle(boolean ellipseStd, IPoint center, double fromAngle, double centralAngle, double rotationAngle, double semiMajor, double minorMajorRatio)```
Sets the center point, starting angle, signed central angle, angle of rotation, ratio of the minor axis to the major axis, and axes.
` void` `queryCenterPoint(IPoint center)`
Copies the center of this arc to the input point.
` void` ```queryCoords(boolean ellipseStd, IPoint center, IPoint from, IPoint to, double[] rotationAngle, double[] minorMajorRatio, boolean[] isCCW, boolean[] minor)```
Copies the center and endpoints, angle of rotation, orientation and major/minor properties into the method parameters.
` void` ```queryCoordsByAngle(boolean ellipseStd, IPoint center, double[] fromAngle, double[] centralAngle, double[] rotationAngle, double[] semiMajor, double[] minorMajorRatio)```
Returns the center point, starting angle, signed central angle, angle of rotation, ratio of the minor axis to the major axis, and axes.
` void` `setCentralAngle(double centralAngle)`
The included (or central) angle.
` void` ```setFromAngle(boolean ellipseStd, double fromAngle)```
The start angle (measured from a horizontal line through the center point) defining where the arc starts.
` void` `setIsCounterClockwise(boolean isCCW)`
Indicates if this elliptic arc is oriented counter-clockwise from its 'from' point to its 'to' point.
` void` `setIsMinor(boolean isMinor)`
Indicates whether the arc is a minor arc or a major arc.
` void` ```setToAngle(boolean ellipseStd, double toAngle)```
The end angle (measured from a horizontal line through the center point) defining where the arc ends.

Methods inherited from interface com.esri.arcgis.geometry.ICurve
`getFromPoint, getLength, getSubcurve, getToPoint, isClosed, queryFromPoint, queryNormal, queryPoint, queryPointAndDistance, queryTangent, queryToPoint, reverseOrientation, setFromPoint, setToPoint`

Methods inherited from interface com.esri.arcgis.geometry.IGeometry
`geoNormalize, geoNormalizeFromLongitude, getDimension, getEnvelope, getGeometryType, getSpatialReference, isEmpty, project, queryEnvelope, setEmpty, setSpatialReferenceByRef, snapToSpatialReference`

Method Detail

### queryCoords

```void queryCoords(boolean ellipseStd,
IPoint center,
IPoint from,
IPoint to,
double[] rotationAngle,
double[] minorMajorRatio,
boolean[] isCCW,
boolean[] minor)
throws IOException,
AutomationException```
Copies the center and endpoints, angle of rotation, orientation and major/minor properties into the method parameters.

#### Description

Given the EllipseStd value, returns the Center Point, From Point, To Point, Rotation Angle, Minor Axis to Major Axis Ratio, IsCounterClockwise value, and IsMinor value of the Elliptic Arc. If EllipseStd = TRUE, the From Point and To Point locations are relative offsets from the Center Point rather than the origin.

#### Remarks

These are the necessary inputs for PutCoords, except in special cases (half ellipse, full ellipse, Central Angle = 0, and Minor to Major Ratio = 0) where the ArcOrientation must know which of these cases exists to ensure that the desired Elliptic Arc is unambiguous. Any of the output parameters can be set to nil if that info is not desired.

-isCCW stands for "is counter clockwise"

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`ellipseStd` - The ellipseStd (in)
`center` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`from` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`to` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`rotationAngle` - The rotationAngle (in/out: use single element array)
`minorMajorRatio` - The minorMajorRatio (in/out: use single element array)
`isCCW` - The isCCW (in/out: use single element array)
`minor` - The minor (in/out: use single element array)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.
`IEllipticArc.putCoords(boolean, com.esri.arcgis.geometry.IPoint, com.esri.arcgis.geometry.IPoint, com.esri.arcgis.geometry.IPoint, double, double, int)`

### putCoords

```void putCoords(boolean ellipseStd,
IPoint center,
IPoint from,
IPoint to,
double rotationAngle,
double minorMajorRatio,
int orientation)
throws IOException,
AutomationException```
Sets the center point and endpoints, angle of rotation, and orientation.

#### Description

PutCoords creates an Elliptic Arc given the EllipseStd value, Center Point, From Point, To Point, Rotation Angle, Minor Axis to Major Axis Ratio, and the Arc Orientation. If EllipseStd = TRUE, the From Point and To Point locations are relative offsets from the Center Point rather than the origin.

#### Remarks

Unless the coordinates of the From and To Points are exactly on the defined Elliptic Arc, PutCoords is likely to create an invalid Elliptic Arc. Therefore, it is highly recommended that another Elliptic Arc creation method is used unless all of the necessary input parameters are exactly known.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`ellipseStd` - The ellipseStd (in)
`center` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`from` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`to` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`rotationAngle` - The rotationAngle (in)
`minorMajorRatio` - The minorMajorRatio (in)
`orientation` - A com.esri.arcgis.geometry.esriArcOrientation constant (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.
`IEllipticArc.queryCoords(boolean, com.esri.arcgis.geometry.IPoint, com.esri.arcgis.geometry.IPoint, com.esri.arcgis.geometry.IPoint, double[], double[], boolean[], boolean[])`, `IEllipticArc.putCoordsByAngle(boolean, com.esri.arcgis.geometry.IPoint, double, double, double, double, double)`

### queryCoordsByAngle

```void queryCoordsByAngle(boolean ellipseStd,
IPoint center,
double[] fromAngle,
double[] centralAngle,
double[] rotationAngle,
double[] semiMajor,
double[] minorMajorRatio)
throws IOException,
AutomationException```
Returns the center point, starting angle, signed central angle, angle of rotation, ratio of the minor axis to the major axis, and axes.

#### Description

Given the EllipseStd value, returns the Center Point, From Angle, Central Angle, Rotation Angle, semi-Major axis length, and Minor Axis to Major Axis Ratio for the Elliptic Arc. These are the same parameters used by PutCoordsByAngle to create the Elliptic Arc. If EllipseStd = TRUE, the From Angle is relative to the rotated semi-Major Axis rather than the X-Axis.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`ellipseStd` - The ellipseStd (in)
`center` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`fromAngle` - The fromAngle (in/out: use single element array)
`centralAngle` - The centralAngle (in/out: use single element array)
`rotationAngle` - The rotationAngle (in/out: use single element array)
`semiMajor` - The semiMajor (in/out: use single element array)
`minorMajorRatio` - The minorMajorRatio (in/out: use single element array)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.
`IEllipticArc.putCoordsByAngle(boolean, com.esri.arcgis.geometry.IPoint, double, double, double, double, double)`

### putCoordsByAngle

```void putCoordsByAngle(boolean ellipseStd,
IPoint center,
double fromAngle,
double centralAngle,
double rotationAngle,
double semiMajor,
double minorMajorRatio)
throws IOException,
AutomationException```
Sets the center point, starting angle, signed central angle, angle of rotation, ratio of the minor axis to the major axis, and axes.

#### Description

Creates an Elliptic Arc given the EllipseStd value, Center Point, From Angle, Central Angle, Rotation Angle, semi-Major Axis length, and Minor Axis to Major Axis Ratio. If EllipseStd = TRUE, the From Angle is relative to the rotated semi-Major Axis rather than the X-Axis.

#### Remarks

This is the recommended way to create an arbitrary Elliptic Arc. However, due to numeric accuracy limitations of computers and trigonometric functions, the From and To Points may be very slightly offset from the expected coordinates. This is important to keep in mind when attempting to connect the endpoints to other segments.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`ellipseStd` - The ellipseStd (in)
`center` - A reference to a com.esri.arcgis.geometry.IPoint (in)
`fromAngle` - The fromAngle (in)
`centralAngle` - The centralAngle (in)
`rotationAngle` - The rotationAngle (in)
`semiMajor` - The semiMajor (in)
`minorMajorRatio` - The minorMajorRatio (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.
`IEllipticArc.queryCoordsByAngle(boolean, com.esri.arcgis.geometry.IPoint, double[], double[], double[], double[], double[])`

### getCenterPoint

```IPoint getCenterPoint()
throws IOException,
AutomationException```
The center point of the arc.

#### Description

The CenterPoint is the point where the Major Axis and Minor Axis of the EllipticArc intersect. The CenterPoint is the point from which all angles and distances are calculated to create the EllipticArc.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
A reference to a com.esri.arcgis.geometry.IPoint
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### queryCenterPoint

```void queryCenterPoint(IPoint center)
throws IOException,
AutomationException```
Copies the center of this arc to the input point.

#### Description

The CenterPoint is the point where the Major Axis and Minor Axis of the EllipticArc intersect. The CenterPoint is the point from which all angles and distances are calculated to create the EllipticArc. You must instantiate the Point before calling QueryCenterPoint. For example,

```
```Dim pPoint as IPoint

Set pPoint = New Point```

```

#### Remarks

The QueryCenterPoint method should be used in performance critical situations, where the center point of several arcs needs to be retrieved. The point is populated (not created) by the method. For example, this can be used to get the center point of several arcs in a loop. Creating the point only once outside the loop may improve performance for large number of arcs.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`center` - A reference to a com.esri.arcgis.geometry.IPoint (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### getAxes

```void getAxes(double[] semiMajor,
double[] semiMinor,
double[] minorMajorRatio)
throws IOException,
AutomationException```
Gets the semi-major and semi-minor axes.

#### Description

Returns the Major Axis, the Minor Axis, and the ratio of the Minor Axis to the Major Axis. The Major Axis is the larger of the two Axes, and the Minor Axis is the smaller Axis. The Major Axis always lies on the line between 0 and Pi Radians in EllipseStd, and the Minor Axis always lies on the line between Pi/2 and 3*Pi/2 Radian in EllipseStd.

#### Remarks

The Axes can be set using PutAxes.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`semiMajor` - The semiMajor (in/out: use single element array)
`semiMinor` - The semiMinor (in/out: use single element array)
`minorMajorRatio` - The minorMajorRatio (in/out: use single element array)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### putAxes

```void putAxes(double semiMajor,
double minorMajorRatio)
throws IOException,
AutomationException```
Sets the semi-major and semi-minor axes.

#### Description

Sets the Major Axis and the Minor Axis. The Major Axis is the larger of the two Axes, and the Minor Axis is the smaller Axis. The Major Axis always lies on the line between 0 and Pi Radians in EllipseStd, and the Minor Axis always lies on the line between Pi/2 and 3*Pi/2 Radian in EllipseStd.

#### Remarks

The Axes can be returned using GetAxes.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`semiMajor` - The semiMajor (in)
`minorMajorRatio` - The minorMajorRatio (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### getFromAngle

```double getFromAngle(boolean ellipseStd)
throws IOException,
AutomationException```
The start angle (measured from a horizontal line through the center point) defining where the arc starts.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Parameters:
`ellipseStd` - The ellipseStd (in)
Returns:
The fromAngle
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### setFromAngle

```void setFromAngle(boolean ellipseStd,
double fromAngle)
throws IOException,
AutomationException```
The start angle (measured from a horizontal line through the center point) defining where the arc starts.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Parameters:
`ellipseStd` - The ellipseStd (in)
`fromAngle` - The fromAngle (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### getToAngle

```double getToAngle(boolean ellipseStd)
throws IOException,
AutomationException```
The end angle (measured from a horizontal line through the center point) defining where the arc ends.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Parameters:
`ellipseStd` - The ellipseStd (in)
Returns:
The toAngle
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### setToAngle

```void setToAngle(boolean ellipseStd,
double toAngle)
throws IOException,
AutomationException```
The end angle (measured from a horizontal line through the center point) defining where the arc ends.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Parameters:
`ellipseStd` - The ellipseStd (in)
`toAngle` - The toAngle (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### getCentralAngle

```double getCentralAngle()
throws IOException,
AutomationException```
The included (or central) angle.

#### Description

The CentralAngle describes the span of the EllipticArc. The CentralAngle is the angular measure between the FromAngle and the ToAngle. The CentralAngle is measured in Radians and is always between -2*Pi and 2*Pi. If the CentralAngle > 0, then the EllipticArc is oriented in a CounterClockwise direction.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
The centralAngle
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### setCentralAngle

```void setCentralAngle(double centralAngle)
throws IOException,
AutomationException```
The included (or central) angle.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`centralAngle` - The centralAngle (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### isPoint

```boolean isPoint()
throws IOException,
AutomationException```
Indicates if the arc is degenerated to a point.

#### Description

IsPoint returns TRUE when the semiMajor axis = 0. IsPoint returns FALSE when the semiMajor axis > 0 (this includes when the CentralAngle = 0, as this is a well-defined EllipticArc.).

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
The isPoint
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### isLine

```boolean isLine()
throws IOException,
AutomationException```
Indicates if the arc is degenerated to a line.

#### Description

IsLine returns TRUE when the minorMajorRatio = 0. This is analgous to the semiMinor Axis having a length of 0.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
The isLine
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### isCounterClockwise

```boolean isCounterClockwise()
throws IOException,
AutomationException```
Indicates if this elliptic arc is oriented counter-clockwise from its 'from' point to its 'to' point.

#### Description

IsCounterClockwise returns TRUE if the CentralAngle is greater than 0. If the IsCounterClockwise values differ, setting IsCounterClockwise changes the EllipticArc to its Complement.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
The isCCW
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### setIsCounterClockwise

```void setIsCounterClockwise(boolean isCCW)
throws IOException,
AutomationException```
Indicates if this elliptic arc is oriented counter-clockwise from its 'from' point to its 'to' point.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`isCCW` - The isCCW (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### isMinor

```boolean isMinor()
throws IOException,
AutomationException```
Indicates whether the arc is a minor arc or a major arc.

#### Description

IsMinor is TRUE when the CentralAngle < Pi (180 degrees). IsMinor also returns TRUE when the semiMajor axis = 0. If the IsMinor values differ, setting IsMinor changes the EllipticArc to its Complement.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
The isMinor
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### setIsMinor

```void setIsMinor(boolean isMinor)
throws IOException,
AutomationException```
Indicates whether the arc is a minor arc or a major arc.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Parameters:
`isMinor` - The isMinor (in)
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### complement

```void complement()
throws IOException,
AutomationException```
Changes this ellipse into its complement; 'from' and 'to' points are unchanged.

#### Description

The Complement of an EllipticArc is the EllipticArc between the ToPoint and the FromPoint of the original EllipticArc that creates a full ellipse when combined with the original EllipticArc. The Complement maintains the same FromPoint and ToPoint as the original EllipticArc, but has the different IsMinor and IsCounterClockwise values.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.

### isCircular

```boolean isCircular()
throws IOException,
AutomationException```
Indicates if this elliptical arc is acutally circular (major and minor axes same length).

#### Description

IsCircular returns TRUE when the minorMajorRatio = 1.

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Supported Platforms

Windows, Solaris, Linux

Returns:
The isCircular
Throws:
`IOException` - If there are interop problems.
`AutomationException` - If the ArcObject component throws an exception.