CircularSegment[] command

acron shared this idea 9 years ago
Answered

There exists

Segment[ <Point A>, <Point B> ]

... Creates a segment between two points A and B.

Segment[ <Point A>, <Number a> ]

... Creates a segment with length a and starting point A.

And there is
CircumcircularSector[Point A, Point B, Point C]

... Creates a circular sector whose arc runs through the three points A, B, and C. Point A is the starting point and point C is the endpoint of the arc.

CircularSector[ <Point M>, <Point A>, <Point B> ]

.... Creates a circular sector with midpoint M between two points A and B.

925f8d37b577fe7e5b76e68016fbf4abHow about this adding this command:
    CircularSegment[ <Point M>, <Point A>, <Point B> ]

It would create the red area below. Yes, there is a workaround, but IMHO a student should be able to use this command to quickly define and find the circular segment of a circle part...b1081e45b490708a6bb21f6184b9f02aThis is one of the few parts of a circle where there is no command at this time. The green triangle is also a circle part but is easy to define with the polygon commands.


I hope the developers will add this command to the command list...


Thank you,


Tony

Comments (6)

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The attached file shows most of the parts of a circle, many of which GG currently incorporates...


Tony

https://ggbm.at/560995

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Hi Tony,


Doesn't CircularArc[ <Midpoint>, <Point>, <Point> ] do what you want when shaded? If you want a different colour border you'll need to add a segment. Or was this the workaround? :)


Simon

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No, the command CircularArc[ <Midpoint>, <Point>, <Point> ] is the arc length of the central angle. When shaded it shows the area of a sector, the CircularArc command does not find the area of the sector.


The segment of a circle is the area bounded by a chord and an arc length of the subtended angle (this formula uses radians)

A = 1/2 r^2 (Θ - sin Θ)


Look at the attachment circleParts2.ggb for most definitions and formulas.


Tonyd9ef916503e169031591c2da6c46abb2

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So you want Area[CircularArc] as a workaround.


I guess you want a tool that creates the circular arc, adds a chord, shades it and outputs the area?


But I agree, a specific in-built tool would be tidier without the extraneous information.

https://ggbm.at/1391001

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So you want Area[CircularArc] as a workaround.


But I agree, a specific in-built tool would be tidier without the extraneous information.

Correct a built-in tool is better, especially since most of the other tools already exist.


Thanks for understanding...


Tony


BTW, I do not usually want to use ggt tools as I am still trying to learn them well enough to teach them...Also, if the term is a common term it should be built-in.

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I know this is an old thread but I wanted to add my support for the comments made by Tony.

As a Circle Segment is such a common circle property it would be fantastic to have it added if possible.


Thanks,

David.


p.s. (If a command does exist now please let me know)

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