Questions tagged [geometric-transformation]

A geometric transformation is any bijection of a set having some geometric structure to itself or another such set. (from Wikipedia)

A geometric transformation is any bijection of a set having some geometric structure to itself or another such set. Specifically, "A geometric transformation is a function whose domain and range are sets of points. Most often the domain and range of a geometric transformation are both R2 or both R3. Often geometric transformations are required to be 1-1 functions, so that they have inverses." [1] The study of geometry may be approached via the study of these transformations.[2] Geometric transformations can be classified by the dimension of their operand sets (thus distinguishing between planar transformations and those of space, for example). They can also be classified according to the properties they preserve:

  • displacements preserve distances and oriented angles;

  • isometries preserve angles and distances;[3]

  • similarities preserve angles and ratios between distances;

  • affine transformations preserve parallelism;[3]

  • projective transformations preserve collinearity;[4]

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Transforming a disk to a ring

I was reading the beautiful book "New Horizons in Geometry" from Apostol and Mamikon. One of the basic ideas from the book is that geometric transformation from a disk to a ring is area-preserving (see image). How could I find the non-linear map…
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Can you map $\mathbb{R}^2$ onto half of $\mathbb{R}^2$ as a bijection?

Basically, can you map all the points on a coordinate plane to unique points on the space above the x-axis? The way I'm imagining it is that the vertical lines infinitely close to the right and left of the y-axis would become y=abs(1/ax) where x>0…
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$AD, BE, CF$ are altitudes in $ABC$. $P,Q$ are points on lines $BC$ and $AB$ so $QP =PF$ and $R$ on $AC$ so $RP =CP$. Prove $ QDRA$ is a cyclic

Let $AD, BE, CF$ be the altitudes of triangle $ABC$ and $P$ be an arbitrary point of side $BC$. Point $Q$ on the line $AB$ is such that $QP =PF$ and the point $R$ on the line $AC$ is such that $RP =CP$. Then $ QDRA$ is …
nonuser
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Quad to quad transformation

I am trying to find a transformation that maps each internal point of my first quadrilateral domain into each point of my second quadrilateral domain. Please see the following image: Each domain is defined by four points and my aim is to find a…
Sturm
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If I have two congruent circles that reflect each other, how would I find its reflection line?

I have these two circles, $\left(-6,\ 0.8\right)$ for the blue circle, and $\left(-3.988,\ -8.159\right)$ for the black circle. Using the formula to find the mid-point of these circles, I got $\left(-4.994,\ -3.6795\right)$. For my assignment I…
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non-rigid transformation for data correction

I am seeking a mathematical method to perform non-rigid transformations of quadrilaterals as demonstrated below. Here you can imagine the four coordinates of a rectangular figure where the data interior to the coordinates has been extracted but is…
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relative transformation of coordinates on a flat surface

I have a few coordinates that form a triangle. I have a relative point to that triangle. if the coordinates get translated to a new triangle I want to calculate the new relative point. How do I do this generally not only for 2 dimensions but for…
MetaStack
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