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geometry[StretchRotation] - find the stretch-rotation of a geometric object
geometry[homology] - find the homology of a geometric object
geometry[SpiralRotation] - find the spiral-rotation of a geometric object
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Calling Sequence
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StretchRotation(Q, P, O, theta, dir, k)
homology(Q, P, O, theta, dir, k)
SpiralRotation(Q, P, O, theta, dir, k)
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Parameters
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Q
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the name of the object to be created
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P
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geometric object
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O
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point which is the center of the homology
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theta
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number which is the angle of the homology
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dir
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name which is either clockwise or counterclockwise
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k
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number which is the ratio of the homology
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Description
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Point O is called the center of the homology, k the ratio of the homology, theta and dir the angle of the homology.
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For a detailed description of Q (the object created), use the routine detail (i.e., detail(Q))
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The command with(geometry,StretchRotation) allows the use of the abbreviated form of this command.
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Examples
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define the parabola with vertex at (0,0) and focus at (0,1/2)
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![parabola(p1, ['vertex' = point('ver', 0, 0), 'focus' = point('fo', 0, 1/2)])](/support/helpjp/helpview.aspx?si=5898/file04138/math196.png)
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![Equation(p1, [x, y])](/support/helpjp/helpview.aspx?si=5898/file04138/math200.png)
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