Questions on the application of Mathematica to geometric problems. You might also consider adding the [graphics] tag, if appropriate.

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-5
votes
1answer
41 views

Calculating the top left corner in a 2d field [on hold]

Given I have a field with several rectangles like shown in the picture. A point with its x and y coordinates are given. The height(h) and the width(w) are also given. How can I calculate the top ...
-2
votes
0answers
33 views

How to solve nonlinear system of four PDE

DSolve[{D[Subscript[g, 11][u, v, t], t] == -2 [Psi][u, v, t] Subscript[L, 11][u, v, t], D[Subscript[g, 22][u, v, t], t] == -2 [Psi][u, v, t] Subscript[L, 22][u, v, t], D[Subscript[L, ...
0
votes
0answers
12 views

Find the shortest distance between the line x + 2y = 1 and the origin [migrated]

The question is as stated, find the shortest distance between the line x + 2y = 1 and the origin of coordinates
0
votes
0answers
42 views

How can I plot 2 concentric fixed circles with a polygon inscribed in one and circumscribed about the 2nd

Can anyone help me with the simplicit code to plot 2 concentric circles and a polygon of sides n (that I can manipulate) inscribed in one circle and circumscribed about the other. However I want the ...
2
votes
2answers
329 views

Draw a circle through 4 points on parabola [closed]

I have two dynamic perpendicular parabolas: $y=ax^2+c, x=by^2+d$, which intersect in four points (the coefficients are chosen that way). There is a fact that we can construct a circle through these ...
7
votes
1answer
216 views

Rigid Rotation of a Point Cloud

If I have a group of points that are aligned along some vector. For example: ...
2
votes
1answer
67 views

Plotting a manifold within an existing surface

I have a dynamical system $\textbf{x}'=\textbf{f(x)}$ where $x\in \mathbb{R}^4$. However, $x_1 +x_2 +x_3 + x_4 =1$ and $0\leq x_i \leq 1$ for $i = 1,2,3,4$, meaning the system lives on the ...
1
vote
1answer
70 views

How Can I plot two concentric circles with a polygon inscribed in one and circumscribed about the other however I want the polygon to manipulated

So this code is to plot two concentric circles with a polygon inscribed in one and circumscribed about the other: ...
1
vote
2answers
58 views

Selecting points in list that are inside a contour [duplicate]

I have a list of points which form a closed (connected) contour or path in two dimensions. I would like to get all points from a second list which satisfy the requirement that they are inside the ...
2
votes
3answers
160 views

Distance from point to line [duplicate]

I'm a newbie with Mathematica and I managed to draw a line and a point in 3D on a graph ...
0
votes
0answers
43 views

Check if interpolated function passes through a specified region

Is there an efficient way to check if a curve that was obtained as an Interpolating Function (from solving differential equations numerically) passes through a given region? I am solving for two ...
-2
votes
0answers
14 views

how to calculate point after rotation [migrated]

I have basic square with width 36 (red) I'm rotating square by XYZ degrees ... in example there is 45 degrees black square is rotated by point 0,0 green square is rotated by center of sqare 18,18 ...
1
vote
0answers
56 views

Mirror image of a point about a line [migrated]

How can I calculate the mirrored position for a point in 2D space? I know the xy-coordinates of the two points which define the vector. I also know the coordinates for the yellow point which I want to ...
1
vote
2answers
106 views

How can I plot two concentric circles with a polygon inscribed in one and circumscribed about the other

So I am new to Mathematica still learning basic codes.. However I need help to become quicker in my research. Can anyone help me with the simplicit code to plot 2 concentric circles and a polygon of ...
1
vote
1answer
87 views

Plot a line passing through two given points in 3D space

How can I plot straight line passing through two given points in 3D coordinates? For example, given the points M1: (2, -2, 0) and M2: (1, -3, -5) ...
2
votes
0answers
103 views

Plotting Seifert surfaces

Is it possible to make a Seifert surface in Mathematica, such as a Seifert surface for a trefoil knot? I was thinking of taking the parametrization equations for a trefoil knot and then somehow ...
0
votes
1answer
69 views

Geodesic circle on a pseudosphere

I am trying to 3D print a portion of the pseudosphere, whose edge is geodesic circle. To do so, I plotted a region of the pseudosphere with the geodesics emanating from a point and I got this: The ...
-2
votes
3answers
113 views

Constructing an Equilateral Triangle Inscribed Inside a Circle

How to plot something like this? I need only the triangle and the 3 circles green. Thank you!
4
votes
2answers
117 views

Arc length parameterization of a list of points?

Suppose I have a curve represented by a list of points in the form $\{\{x_0, y_0\}, \{x_1, y_1\}, ...\}$. How to generate a list of numbers $\{s_0, s_1, ...\}$ where $s_i$ is the distance of ith point ...
0
votes
3answers
37 views

A shift of a trapezoid and a connect to the original

I have: Graphics[{ Line[{{0, 0}, {30, 0}, {55, 50}, {-25, 50}, {0, 0}}] }] Now, I'd like to keep it in place, then shift a copy up and to the right, then ...
18
votes
5answers
467 views

Is there a numerical method/built-in to calculate the boundary of a set of graphs?

Recently, I encounted a geometry problem in my work. For a curve-family that owns the following parametric equation: $$E(t,\theta)= \begin{pmatrix} x_E(t,\theta) \\ y_E(t,\theta) \end{pmatrix}$$ ...
11
votes
1answer
143 views

How to make a two letter monogram in 3d like the one on www.mymo.is? [duplicate]

I want to achieve the same effect like the project on http://www.mymo.is/. By taking two letters and combine them in 3d, you can get a complex shape that looks like one letter on the one side and the ...
9
votes
1answer
762 views

Max & min distance between two moving points

I am trying to find the minimal and maximum distance between two moving points with Mathematica in an interval. For example, ...
8
votes
4answers
226 views

Probability of a random point inside the intersection of two triangles

I hope I can explain this problem clearly. It has been bothering me for sometime and I do not know how to solve it even with Mathematica's help. Right isosceles triangle E (the large red triangle) ...
0
votes
0answers
44 views

How to apply a shear matrix?

I have curves that I made to create a design using graphics[], and I wanted to apply a shear to this. I know/think that a shear comes in the {1,lambda}{0,1} form, and that I'm supposed to my multiply ...
3
votes
1answer
94 views

Angle between two vectors in spherical coordinates [closed]

I have two vectors: H = {1, 0, π/4}; EA = {1, 0, 0}; Which I want to be in {r, Phi, Theta} - which would should give an angle between the two vectors as ...
1
vote
1answer
125 views

Draw Vectors in Spherical Shell and then Animate

I want to draw three vectors inside a spherical shell. One of the vectors will be moving, the others will be stationary. However, the animation is the next step. For now, I would like to get the ...
2
votes
2answers
149 views

HIghlight intersection of two disks [duplicate]

I tried this: reg1 = Disk[{0, 0}, 1]; reg2 = Disk[{1, 0}, 1]; reg3 = RegionIntersection[reg1, reg2]; Then this: ...
4
votes
1answer
203 views

geodesics' on torus

Is it possible to draw geodesics between the points in a path on a torus - toroidal surface? geodesics: generalization of the notion of a "straight line" to "curved spaces" ...
16
votes
0answers
168 views

Bug in RegionMember?

Bug persisting through 10.4.1 RegionMember (new in V10) appears to have a bug. For some polygons it finds points that are clearly outside to be "members" of the ...
3
votes
1answer
106 views

hippocrates moons for any shape

Can someone help me create code for a hippocrates moons on random shape with given amount of edges? I want to make something like this: when you press button, it asks you for the amount of ...
15
votes
2answers
348 views

How to export textures?

Is there any object geometry format for which Mathematica supports the exporting of textures for external (non-Mathematica) use ? If not does anyone know of work arounds? All the texture primitives ...
1
vote
0answers
78 views

Intersecting ellipsoids

First of all I know that findng whether two ellispoids intersect is complicated and there are specific algorithms created for this purpose (see, for instance, [1]. Actually, I am trying to follow this ...
2
votes
0answers
87 views

Wolfram alpha algorithm for geometric packing in 2D [closed]

Is there any way to gain access to the algorithm that wolfram alpha uses? More specifically, I want to pack small circles in hex and square patters in a larger cicle ...
2
votes
2answers
184 views

intersecting cylinders

I try to replicate the two figures of two intersecting cylinders from here. I tried ...
1
vote
0answers
86 views

Intersection of two volumes

I would like to know the volume of the intersection of a cone and a cuboid : ...
4
votes
1answer
109 views

Tell if a point is inside a FilledCurve

Convert a letter into a FilledCurve: ...
1
vote
3answers
109 views

How do I tell if two sets of dots are in some way similar?

I have two sets of dots (x,y coordinates) and I'd like to figure out if there's a way to find out if the second set of dots is (more or less) "close" to the first one. I may plot these two sets in ...
1
vote
0answers
78 views

Easy way to get the boundary of a geometric object [closed]

I am trying to define von Neumann boundary conditions for a prism. To do so I need the boundary of the geometric object. I can't seem to find an easy way to do this. I have tried to hard code a ...
5
votes
1answer
114 views

Minimal perimeter of all possible polygons

We had a fun problem for a student activity today: Let $P(z) = z^8 + \left(4\sqrt{3} + 6\right)z^4 - \left(4\sqrt{3} + 7\right)$. What is the minimum perimeter among all the $8$-sided polygons in the ...
0
votes
1answer
94 views

How do I create a function to rotate a rectangle about its origin? [closed]

I am new to Mathematica and was trying some new things. I wanted to rotate a rectangle using a rotation matrix by any angle theta from say o to 2pi. I could do it using predefined Mathematica ...
5
votes
3answers
169 views

Simple triangular meshes of primitive shapes

I'd like to generate triangular meshes or a cylinder and sphere primitives as part of a lattice meshing program I am writing to experiment with Mathematica. Consider the following snippet: ...
3
votes
3answers
387 views

intersection between polygon. Algorithm to check it [closed]

I'm working on an algorithm which should check if two polygons, described by their vertex coordinates, are: one inside the other, are intersecting or are separated image below describe this three ...
2
votes
0answers
125 views

Animate FromQuarternionTo3DRotation nb file with 4 quarternion values

I have a csv file. Inside the csv file, there are few rows of 4 quartenion values. I would like to animate the quarternion nb in http://demonstrations.wolfram.com/FromQuaternionTo3DRotation/ I ...
1
vote
0answers
40 views

Creating a triangle from the difference of two points [closed]

I'm attempting to create a triangular area from the difference of two points. I basically have a straight line that could be the length of 1. I would like to create points on both of the sides of the ...
1
vote
0answers
102 views

How to plot several small circles in a bigger circle [closed]

I want to plot several small circles in a bigger one with constraint minimization. The distance between any two small circles must be >= to 2*the radius in order not to enter one another. When I ...
3
votes
1answer
74 views

How to determine the value of an angle starting from an image? [duplicate]

I have two lines drawn with Mathematica, how do I calculate the angle between these two lines to have the numeric value of that angle? Thank you
1
vote
2answers
173 views
0
votes
0answers
33 views

How to put n circles on a sphere [duplicate]

I have a piece of code that generates a circle on a sphere, but the problem is, this code creates only one circle. How can I change it in order to create n circles on the same sphere? Do I have to put ...
4
votes
4answers
335 views

Picking points in a plane under a curve given by a list

Suppose that I have a set of points in a plane, which range from $x\in [0,20]$ and $y\in[0,10]$, and a curve given by a list of points in the same region: ...