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11 votes
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Generate random smooth 2D closed curves

Since your figure is a closed loop, its parametric curves $x(t)$ and $y(t)$ must be periodic functions. This suggests one way to generate such figures, by constructing random smooth periodic functions ...
rchilton1980's user avatar
  • 4,936
9 votes
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How to visualize multidimensional (d>10) function

I doubt there is a standard tool/technique for this kind of task. Nevertheless, there are some approaches. You would need at least one of the following strategies, according to ref. 1 (ch. 8): ...
nicoguaro's user avatar
  • 8,524
8 votes
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Visually appealing ways to plot singular vector fields with matplotlib or other foss tools

[I took your sample program as a starting point and adapted Colormap Normalization from the matplotlib wiki.] Almost everything of the picture just looks red. Indeed. They problem is that there ...
Henri Menke's user avatar
8 votes
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Visualizing the solutions of the Differential equations by varying different parameters

You can try Geogebra (it is free). With SolveODE command and sliders you can do what yo want. For the usage of SolveODE command see. For example by using following command ...
Ömer's user avatar
  • 643
7 votes
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3D contour mesh computation

I think you could use the "marching cubes" algorithm. If memory serves, it requires a grid of samples as input, so at the very least you should be able to sample your function and run the algorithm as-...
rchilton1980's user avatar
  • 4,936
6 votes
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How to create an optimal pizza delivery plan and how to visualize it

Problem Formulation I can't guarantee that this is a perfect (or smallest-possible) formulation of the problem, but maybe it will help guide a better one. The road network is a directed graph ...
Tyler Olsen's user avatar
  • 1,512
5 votes

3D contour mesh computation

In addition to the voxel-based approach that rchilton suggests, you could also look at Delaunay-type algorithms. For example, the Computational Geometry Algorithms Library (CGAL) has some built-in ...
Daniel Shapero's user avatar
5 votes

Generate random smooth 2D closed curves

What I ended up doing is to download thousands of random images, smooth them with a Gaussian filter, and extract contours at different levels. I took 2-3 closed contours from each blurred image and ...
gipouf's user avatar
  • 203
4 votes
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C++ library unstructured mesh writer to VTK format (or similar)

I think you are looking for Kitware VTK, basically, the main library for interaction with VTK files. Examples page will contain a lot of samples, including the one you are looking for: output of an ...
Anton Menshov's user avatar
  • 8,692
4 votes

Visualizing the solutions of the Differential equations by varying different parameters

You can use DifferentialEquations.jl Online to visualize solutions to differential equations without a hassle. It's built using the Julia suite DifferentialEquations.jl, and the online interface is a ...
Chris Rackauckas's user avatar
4 votes

Pre/Post-processor for an academic finite element solver

Cubit/Trelis for generating meshes (Exodus.II files) and Paraview/Visit usually work well for low order FE codes. The advantage of Exodus.II is that it is a standard and therefore edge/side/face ...
stali's user avatar
  • 1,759
4 votes
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Recommended visualization tools for higher order finite element solutions?

New versions of VTK support what you are asking for, and new versions of Paraview can also display this. The current version of Visit can not yet, though, at the time of writing this. The trick is ...
Wolfgang Bangerth's user avatar
4 votes
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Finding a best fit line for the upper bound on an $x$ vs $y$ relationship

We can formulate the task of finding a straight line bounding the cloud of data points as constructing a straight line that touches the data set at least at two points, and the rest of the data points ...
Maxim Umansky's user avatar
3 votes
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15 noded triangular elements in paraview

Unfortunately (unless things have changed very recently) VTK doesn't fully support anything higher than second order cells in terms of mesh visualisation and filtering. Various common workarounds ...
origimbo's user avatar
  • 2,249
3 votes

Visualization of quadtree & octree grids

In my case when I was doing the multilevel refinement, I used to write grid files at different levels separately. Usually the level 0 is a base coarse mesh which remains fixed. And for level 1 and up, ...
Tanmay Agrawal's user avatar
3 votes

Visually appealing ways to plot singular vector fields with matplotlib or other foss tools

As already mentioned, the main problem is not with the visualization algorithm but with the data. Hence, you should use a different scaling (normalization) for the values. Furthermore, if you want to ...
nicoguaro's user avatar
  • 8,524
3 votes

Alternatives to Mathematica

Having used Mathematica, then trying Sage, and now SymPy/SymEngine in Julia, the clear winner is SymEngine.jl. Sage was hard to get working, was very slow, and I found it very hard to develop my own ...
Chris Rackauckas's user avatar
3 votes

Alternatives to Mathematica

Sage would be perfect for classroom use. I once assisted a professor with classroom demonstrations of Physics, and it worked out pretty well. Working with Sage does not require advanced programming ...
Raziman T V's user avatar
3 votes
Accepted

Magnetic field simulation and visualization on Mac OS X?

For this purpose you need to use a simulation software. One of the most common methods in Electromagnetics would be Finite element method, but you can also find Boundary Element Methods or Finite ...
nicoguaro's user avatar
  • 8,524
3 votes

Algorithms for (adaptive?) function plotting

I found this topic and thought I should share the developer issue page for adding this to the Julia library Plots.jl. We tried a bunch of techniques to see what would give good results, starting from ...
Chris Rackauckas's user avatar
3 votes
Accepted

Recreating this 3D density plot in ParaView

You will have to interpolate the points to a 3D grid (a regular grid will do) and then do the volume rendering. See https://www.visitusers.org/index.php?title=Volume_Rendering for some examples.
Biswajit Banerjee's user avatar
3 votes
Accepted

Visualization of 3D streamlines in ParaView

StackOverflow has a similar question to yours. Although, it is not exactly the same. The following is a pipeline for what you want: ...
nicoguaro's user avatar
  • 8,524
3 votes
Accepted

Efficiently plot a finite element mesh solution with Matplotlib

You might be interested in trying other visualization tools such as ParaView, Mayavi or PyVista. But, since the question is about Matplotlib, I would suggest that you use ...
nicoguaro's user avatar
  • 8,524
3 votes
Accepted

Scipy Find Peaks

According to the documentation, find_peaks returns the indices of the peaks. But in your first plot command, the abscissas ...
rob's user avatar
  • 176
2 votes

How can I plot piece-wise defined function in some easily-accessed open-source tool?

I think a piecewise function is a perfect case for using a closure. This frees you from the need of having a cumbersome n as an argument. ...
kotchwane's user avatar
  • 121
2 votes

3D visualization in MATLAB

As mentioned by @jlk, what you want is a 3D visualization, or visualization of Three-dimensional data. Most approaches for 3D visualization fall into one of the following categories (from reference 1)...
nicoguaro's user avatar
  • 8,524
2 votes

In practice, what are the most useful ways to visualize 2d fluid flow, to tell what is happening in the simulation? Esp for verification and debugging

A good way to obtain to verify the CFD portion of your code is to proceed using the method of manufactured solution (MMS). You can look at the book by Oberkampf & Roy or even this article by me. ...
BlaB's user avatar
  • 1,157
2 votes

How do I migrate from Legacy VTK (Structured Points) to XML (Structured Grid)?

I recently came across a Python tool that claims to convert between all kinds of different mesh formats. I haven't gotten around to trying it yet, but maybe it can help you: https://github.com/...
cfh's user avatar
  • 586
2 votes

How to report non-monotonic runtimes in convergence plots

It sounds like you actually have three pieces of information here -- h, error, and runtime. Plotting accuracy vs runtime isn't that useful if there is no correspondence with h (and so the user of ...
Ethan Coon's user avatar
2 votes
Accepted

Which statistical method should I use for comparing machine run-time of two algorithms?

This is a typical use case for a paired t-test. The idea is to consider only the runtime difference $\Delta t$ for each problem and test for the null hypothesis $E(\Delta t)=0$. For a step-by-step ...
cdalitz's user avatar
  • 481

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