Questions tagged [visualization]
Questions relating to graphing and displaying numerical data
140
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How can I make the color range symmetric around zero in Paraview?
I often use diverging colormaps (like the Paraview default "cool-to-warm") with a color range that is symmetric around zero, e.g. to visualize areas of tensile (red) and compressive (blue) ...
- 21
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Does loss landscape provide a means to compare optimization algorithms?
I'm comparing two optimization algorithms for deep neural networks. To that end, I train a network with the same data and starting rom the same initial weights using two different optimization ...
- 111
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answer
108
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Finding a best fit line for the upper bound on an $x$ vs $y$ relationship
I am trying to do linear regression on the following conceptualized problem. I have a set of data in pairs $(x, y)$. I know that $y$ is bounded by a linear function $f(x) = mx + c$. I want to estimate ...
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700
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Rotate a 2D contour plot through 360 degrees to create 3D plot (Python, Mayavi/Matplotlib)
I have three 1D arrays, which represent radius, height, and an intensity measured at that point. I have plotted these to create a 2D contour map. A simple example of the way in which the data is ...
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34
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3D web visualization with arbitrary cutting plane
How can I visualize 3D data volumes with arbitrary cutting plane on web pages? I could not find a library that allows so.
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100
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Scipy Find Peaks
I am trying to find the peaks. I have list x_period and y_power. I find the peaks from the ...
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44
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How to make a time-parametrization slower around a point but not too slow?
For animation purposes (see below) I need to use a parametrization which 'slows down' near a specific value;
More precisely, I am looking for a 'nice' monotonically increasing function $r:[0,1] \to [...
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206
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Developing a meshfree contouring algorithm
I would like to find the contours of a scalar function $u(x,y)$ available as a discrete set of function values $u_i = u(x_i,y_i)$ over a scattered set of points $(x_i,y_i), i=1,...,N$.
In my case, the ...
- 524
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2
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668
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vtk python visualizing scalar data on quad mesh
I'd like to visualize scalar data located on the nodes of a quad mesh (2D) using VTK in Python3. The closest example I've found is vtk quad mesh, but it only seems to visualize the mesh, not data on ...
- 668
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553
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How to calculate the average velocity over a surface through time using paraview?
My problem is a little more complex, but here is a simplified similar model.
Let us consider a fire source inside a box and the hot gases (burnt or unburnt) from the combustion are going out of the ...
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Generate random smooth 2D closed curves
I would like to know how can I generate a collection of random 2D closed smooth curves.
I thought about generating a random 3D surface with random peaks, and then intersecting the Z=0 plane with it, ...
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472
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Plotting a Magnetic Field in Spherical Coordinates in Python
I am modeling a Helmholtz Coil as two dipoles from far away and I want to plot the magnetic field.
$$\mathbf{B}(\mathbf{r}) = \frac{\mu_0 |\mathbf{m}|}{4\pi r^3}\left(2\cos\theta\,\hat{\mathbf{r}} + \...
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2
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712
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Visualization of Quad/Octree data Structures
I have a simple C++ quadtree implementation. The implementation subdivides node into four children as if there is more than one point in that particular node. At the moment I want to visualize how ...
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57
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Stress visualization for structured and unstrcutured mesh
I put together a FEM solver to do some structural analysis. At the moment I am trying to add stress visualization feature to my code. The post-processing is done with Paraview and the results with ...
- 570
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79
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Numerical flow visualization in 2D for a moving boundary,
I have a rigid body that moves according to a set of governing ODEs, and I'd like to numerically visualize the vortices that are shed by this object. How could I proceed?
I've been reading up on the ...
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Using Axis Equal for Matlab simulation plots of the SIR model gives very flat solution curves
My professor taught us to always use the Matlab command axis equal for our simulation data plots - for all of our homework assignments.
However, in studying the ...
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438
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How to plot a heatmap under a curve?
If I were to have a data for a one-dimensional system evolving in time, essentially a two-dimensional array, and the array at each point in time is of the same size, how would I produce something like ...
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148
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How to visualize multidimensional (d>10) function
I need to visualize the response of a function
$$y=f(x_1, x_2, … , x_d)$$
with d in the order of 10-12 (the function f was sampled using finite element simulations). For lower-dimensional design ...
- 560
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0
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106
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3D log density plot in ParaView
I have a .csv file of thousands of (x,y,z) point particles that I would like to visualize in ParaView. I am able to plot a 3D scatterplot using the TableToPoints, and by decreasing point opacity I can ...
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Compute cell values and isosurface constant from density values of particles
I am trying to reconstruct the surface for a fluid simulation based on a list of particles using the Marching Cubes algorithm. From different resources, such as http://paulbourke.net/geometry/...
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271
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User friendly scipy optimize wrapper package?
I'm creating too much throw away code for interfacing with the scipy optimize package in a user friendly way. (See code below for example of interruptible optimization that keeps last optimization ...
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Extracting raw data from a graph
I am supposed to do black-box modeling, I need the input and output data for training, however, the authors didn't agree to share the raw data with me, I can only use their publication where these ...
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Efficiently plot a finite element mesh solution with Matplotlib
I am looking for the most efficient way to plot a mesh using Matplotlib given the following information, coordinates of each node, what nodes belong to each element, and the value each node has. Below ...
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184
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Properly sizing ParaView plots for LaTeX [closed]
I would like to make a visualization with ParaView for a paper. In order to have a high quality look, I would like the image to be, say, 300 dpi (or vector graphics). Moreover, since I know the column ...
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771
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Visualization of 3D streamlines in ParaView
Essentially I want to use paraview to recreate a flow visualization like the one shown in the picture above. I am able to create the 3d flow lines using a pipeline that looks like
...
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41
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Piecewise-linear Continuations vs Marching Squares/Cubes
It seems that both piecewise-linear continuation and marching squares are methods to produce iso-contours of a scalar function given the function's values on a grid. It seems that piecwise-linear ...
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203
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Visualizing a trajectory in VMD
So, I've written a short python program simulating diffusion in 2D; in essence each particle is behaving like a random walker. The output is a 3D tensor, which for 4 particles and 10 timesteps, looks ...
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874
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Recommended visualization tools for higher order finite element solutions?
Is there any software available which can directly render higher order finite element results? In particular, 3D finite elements would be preferable. It seems gmsh has some capability in this regard ...
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477
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Plotting or Visualizing a Higher dimensional vector field
I am trying to visualize a higher dimensional vector field. Is there a way to do this. I asked this question here, I was told to post it here.
As an example, one can use
$$\begin{eqnarray}
\dot{x}...
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257
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Which statistical method should I use for comparing machine run-time of two algorithms?
I am comparing the run-time of two algorithm by solving different instance of the problems. Sample of my data:
...
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483
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Showing date in Paraview's Annotate Time Filter
I have a time dependent data set where each frame corresponds to a certain date. I need to show the time annotation, much like what Annotate Time Filter does, but show the date instead of time as a ...
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547
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Recreating this 3D density plot in ParaView
I want to do somethings similar to the plot found at the bottom of this blogpost, which I found via this post in ParaView, which seems to have been the original Application used to generate the plot.
...
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C++ library unstructured mesh writer to VTK format (or similar)
I am working on a 2D unstructured code in C++. I am using gmsh to generate a 2D unstructured mesh and reading it into my program with a library called ...
4
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2
answers
641
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3D contour mesh computation
I have the value of a function in three dimensions, $f(x, y, z)$, which varies smoothly.
I would like to compute a 3D mesh where $f(x, y, z)$ has a particular value.
Are there algorithms to do this? ...
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98
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How to report non-monotonic runtimes in convergence plots
Let's say I have an algorithm that can be tuned by a parameter $h>0$ and is expected to converge as $h\to 0$.
I want to study the computational complexity of this algorithm, i.e., how the ...
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148
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temperature profile on axial direction of a chamber
I have a task to plot average temperature profile at each cross-section in the axial direction of a combustion chamber. I have $x$, $y$, $z$ coordinates data in excel as well as the corresponding ...
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235
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Code to output VTK point data from decomposed domain for Paraview [closed]
I am developing a parallel 2D CFD code in C++ using PETSc and would like to use it as an opportunity to learn about VTK/Paraview. Right now, I have each processor output an ASCII file for the portion ...
0
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2
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279
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How to represent CFD result when I use grid-centered FVM?
My variables are stored at the center of the cells. How can I transfer these values to grid points? If I calculate the algebraic average value there may be a shock.
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0
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3D visualization of the results of a 2D simulation in COMSOL
Considering that COMSOL forum is dead and CFD-online is not responsive, I'm gonna try asking my question here:
I have done a 2D simulation in COMSOL multiphysics. I have two independent variables x ...
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684
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How to create an optimal pizza delivery plan and how to visualize it
This question is quite open, and the actual problem comes from something you would probably consider an everyday niche (something you'd probably take for granted without really thinking about it). ...
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How do I migrate from Legacy VTK (Structured Points) to XML (Structured Grid)?
The documentation is fairly confusing and I know that I need to keep track of the actual grid location of my data. Writing a python script to convert binary data into this vtk format. I want to leave ...
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3
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Pre/Post-processor for an academic finite element solver
I'm currently developing a finite element solver for academic/research purposes. Therefore I'm searching for a pre- and postprocessor in my toolchain.
For a previous project I have used gmsh as a ...
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Visualizing the solutions of the Differential equations by varying different parameters
Actually I am interested in analyzing the soution to the ODE given as $\frac{dy}{dx} = A + By + C\sin(y) , y(l) = m$ and check how the solution gets affected like whether they exist or not depending ...
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460
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3D visualization in MATLAB
I have a function of 3 variables like $V= f(r_1, p, r_2)$, I want to plot these 4 data in one graph to be able to capture the behavior of V with respect to all three variables.
I searched a little ...
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482
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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
My simulation creates a 2d grid of vectors and scalars (EDIT of velocity, depth etc), at 60 frames per second. Is it correct? It looks sort of right... but who knows?
How can I tell what's happening - ...
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Rescaling x-axis data in Paraview
I am working with VTK legacy files containing vector information. The files have incremental extension representing a file series as defined by this link.
When applying the filter "Plot Selection ...
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437
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15 noded triangular elements in paraview
I am modelling a soil medium in plane strain and would like to determine if paraview supports the 15-noded triangular element as shown on this link.
On the documentation I am only seeing elements up ...
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VTK: Missing Streamlines due to error in Runge-Kutta method?
We are using Kitware VTK to visualize our models. When we display streamlines, it sometimes happens that a single streamline is left out. This can be especially seen when duplicating a model several ...
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89
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Dynamic Analysis and Visualization of Laminate Mindlin Plate
I am trying to make the jump from a FEM plot of a static load applied to Mindlin laminate plate to a surface visualization of various Mode Shapes of the Laminate Plate. For that, I understand that the ...
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2
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459
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Alternatives to Mathematica
looking to introduce a mathematics program in my work, I would have 2 uses:
In a classroom (high school level), providing good visualisation of physics ideas, and making my lecture more interactive. ...