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PlaneGeometry (version 1.6.0)

EllipticalArc: R6 class representing an elliptical arc

Description

An arc is given by an ellipse (Ellipse object), a starting angle and an ending angle. They are respectively named ell, alpha1 and alpha2.

Arguments

Active bindings

ell

get or set the ellipse

alpha1

get or set the starting angle

alpha2

get or set the ending angle

degrees

get or set the degrees field

Methods

Method new()

Create a new EllipticalArc object.

Usage

EllipticalArc$new(ell, alpha1, alpha2, degrees = TRUE)

Arguments

ell

the ellipse

alpha1

the starting angle

alpha2

the ending angle

degrees

logical, whether alpha1 and alpha2 are given in degrees

Returns

A new EllipticalArc object.

Examples

ell <- Ellipse$new(c(-4,0), 4, 2.5, 140)
EllipticalArc$new(ell, 45, 90)

Method print()

Show instance of an EllipticalArc object.

Usage

EllipticalArc$print(...)

Arguments

...

ignored

Method startingPoint()

Starting point of the reference elliptical arc.

Usage

EllipticalArc$startingPoint()

Method endingPoint()

Ending point of the reference elliptical arc.

Usage

EllipticalArc$endingPoint()

Method isEqual()

Check whether the reference elliptical arc equals another elliptical arc.

Usage

EllipticalArc$isEqual(arc)

Arguments

arc

an EllipticalArc object

Method complementaryArc()

Complementary elliptical arc of the reference elliptical arc.

Usage

EllipticalArc$complementaryArc()

Examples

ell <- Ellipse$new(c(-4,0), 4, 2.5, 140)
arc <- EllipticalArc$new(ell, 30, 60)
plot(NULL, type = "n", asp = 1, xlim = c(-8,0), ylim = c(-3.2,3.2),
     xlab = NA, ylab = NA)
draw(arc, lwd = 3, col = "red")
draw(arc$complementaryArc(), lwd = 3, col = "green")

Method path()

The reference elliptical arc as a path.

Usage

EllipticalArc$path(npoints = 100L)

Arguments

npoints

number of points of the path

Returns

A matrix with two columns x and y of length npoints.

Method length()

The length of the elliptical arc.

Usage

EllipticalArc$length()

Returns

A number, the arc length.

Method clone()

The objects of this class are cloneable with this method.

Usage

EllipticalArc$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Examples

Run this code

## ------------------------------------------------
## Method `EllipticalArc$new`
## ------------------------------------------------

ell <- Ellipse$new(c(-4,0), 4, 2.5, 140)
EllipticalArc$new(ell, 45, 90)

## ------------------------------------------------
## Method `EllipticalArc$complementaryArc`
## ------------------------------------------------

ell <- Ellipse$new(c(-4,0), 4, 2.5, 140)
arc <- EllipticalArc$new(ell, 30, 60)
plot(NULL, type = "n", asp = 1, xlim = c(-8,0), ylim = c(-3.2,3.2),
     xlab = NA, ylab = NA)
draw(arc, lwd = 3, col = "red")
draw(arc$complementaryArc(), lwd = 3, col = "green")

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