99 views

### Extract a region from a list of points [duplicate]

I need to extract a region out of a list of points. My points are displayed as follows: I have divided the points in three different regions and then joined them, R1, R2 and R3 are the list of points ...
• 53
702 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: $$E(t,\theta)= \begin{pmatrix} x_E(t,\theta) \\ y_E(t,\theta) \end{pmatrix}$$ ...
• 625
2k views

### How do I create a triangulated surface from points?

I have a set of points in a nx3 matrix and I would like to convert them into a surface, so that I may calculate its surface area. The function ListSurfacePlot3D creates the surface how I want it. ...
• 215
2k views

### Joining points into 3D surface

This seems like a simple problem, but I can't find any questions like it here so I'm making a new one. Apologies if I missed one. I have a list of points contained in a file which can be visualized ...
• 635
2k views

### How can an envelope be drawn around a scatter plot?

Can Mathematica be used to create a ListPlot with the feature shown below; a line around the cloud of points? I am not entirely sure what rule would create the desired effect (i.e., what points ...
• 2,685
1k views

### Smooth 3D plot with colour of scattered data

I have a set of scattered 3D points with coordinate (x,y,z) and an intensity associated with it. I would like to do a smooth surface with the intensity being represented by the colour. My points ...
• 175
345 views

### How to plot customly-shaped set of 3D points each connected to its neighbors?

Consider the following code: ...
• 7,172
284 views

### Plotting displacement values over defined region

I have a deformed 2D region of triangular Elements specified by their Nodes in $x$ and $y$ coordinate system. In addition, I ...
• 163
1k views

### Create a filled ListPlot, where the points in the list come from within the regions rather than from the region boundaries

Is it possible to fill, color, under the points in ListPlot where the points define the area and the boundary? Assuming that the number of points are large enough ...
• 259
533 views

### Strange extrapolation in ListContourPlot?

I have some Table of {x,y,z} values (energy as a function of radial and azimuthal frequencies in a galaxy if you care to know): ...
• 23k
206 views

### Plot geologic profile of layers

I am trying to plot a set of layers with different values of densities (density profile). Geometry ({x,z} values) of 15 interfaces of layers look like this: while ...
• 641
220 views

### Custom interpolation algorithm

Suppose I have a list to create a list density plot, the list format is: list = {{0.5, 0.5, 0.0}, {-0.5, 0.5, 1.0}, {1.0, -0.45, 0.0}, {0.0, 0.0, 0.0}} The size ...
360 views

### Regression /Bug in DelaunayMesh from 10.3.1 to 10.4

Bug introduced in 10.4 and persists through 11.1 In answering this question, I realized the OP and I were obtaining different results from the alphaShapes2D code. ...
• 33.1k
930 views

### Retrieving boundary points of concave hull (or alpha shape) in 3D

I am trying to find the boundary points of some concave 3D region which is described by a list of points. If the region were convex I would take the convex hull and simply extract the coordinates ...
• 4,491