Questions tagged [interpolation]

Questions on the interpolation functions in Mathematica (Interpolation[], ListInterpolation[], FunctionInterpolation[], InterpolatingPolynomial[], etc.)

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InterpolatingFunction in NSolve

I'm trying to get NSolve to solve a simple system of equations. It makes use of various interpolating functions (for thermodynamic properties). I can solve the system outside of NSolve by ordering the ...
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1answer
98 views

Table and FindRoot of a two-variable interpolated function

I am having difficulty solving for the roots of the following interpolating function: ...
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1answer
25 views

Having a question on how should i interapolate using vectors [on hold]

I have two vectors(one dimensional matrices) which are in same length. One of them stands for "x" variable and the other corresponds to "y" which is dependent to "x". my question is that is there any ...
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1answer
38 views

The labels in the plot don't appear

the labels in the plot doesn't appear, axeslabel, plotlabel and plotlabels. ...
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38 views

Obtaining the equation type of an interpolated function

I used InterpolatingFunction on a set of points. How can I know the type of that equation ? (polynomial, sinusoidal, logarithmic,etc...). I am looking for a general case answer. Here is an example ...
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1answer
47 views

Mesh quality error with interpolation of table

I am trying to interpolate a table of the following form. {{x1,y1,z1},{x2,y2,z2}...} Where z depends on x and y, and x ranges from 0.01 to 1 in steps of 0.01, ...
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2answers
167 views

How can I fit a function onto a histogram?

SampleData = RandomVariate[RayleighDistribution[3], 5000]; Histogram[SampleData] This creates a histogram that (in my case) looks something like this: I want to ...
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1answer
34 views

How to obtain the correct interpolation for the following data?

I have a dataset DistrTemp.dat. It represents a set of data in the form {{x,y,z,f[x,y,z]}}. Here, x defines a system, while ...
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Deriving a probability density function from data without interpolation

I have a dataset having the form {{x1, y1, z1, f[x1, y1, z1)}, ...}, correspondong to coordinates and values of the probability density of a distribution. I am ...
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35 views

Interpolation of multidimensional data: some domains are lost

I am trying to make a reasonable interpolation of a dataset having the form dataset = {{x1,x2,x3,f[x1,x2,x3]},...}. I to the interpolation in the following way: <...
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0answers
18 views

Extra interpolation in ListPointPlot3D

I'm trying to plot a 3D surface using ListPointPlot3D and it looks almost right, but for some reason it's trying to connect points that should not connect. I think it's confused because the surface is ...
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1answer
57 views

Interpolation function error: The quality of the underlying mesh is too low

Consider a dataset BplustoPiXlight.dat (alternative link). I import it and try to interpolate: ...
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42 views

BSpline vs natural spline [closed]

The BSpline in mathematica is defined mathematically here. These BSplines constitute basis for any Spline. But how do I define natural splines in mathematica, i.e. splines that are linear left of the ...
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How to speedup the following integral?

Consider the following distribution and its interpolation: ...
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2answers
62 views

Interpolation works slowly

Consider the following code: ...
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1answer
48 views

ElementMeshInterpolation and C1 splines

I am trying to use NDSolve`FEM`ElementMeshInterpolation on a triangular structured grid constructed from a Delaunay triangulation with zero area triangles dropped. ...
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0answers
78 views

Parallel evaluation of RandomVariate for an InterpolatingFunction

I need to generate a lot of point according to a given distribution. I don't have an analytic form of this distribution so I am using an InterpolatingFunction of ~100 points computed numerically. I ...
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22 views

Computing the volume enclosed by revolving a B-spline

I would like to ask if it's possible to get a function from a B-spline curve besides InterpolatingPolynomial[...]. I'm trying to use the function to compute the ...
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2answers
35 views

Calculation using interpolating function

Say I have two replacement rules in terms of interpolating functions. ...
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1answer
51 views

2D interpolating function doesn't reproduce data

I have the following 2D data set: ...
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1answer
64 views

Problem with fit

I am trying to find a proper matching function for the following data set: ...
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1answer
135 views

Meaning of InterpolationOrder -> All for multidimensional interpolation

What specific method does Interpolation use for unstructured multi-dimensional data when we set InterpolationOrder -> All? ...
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28 views

Optimisation in the solution of Newton Interpolation

I have an exercise in which I have to solve the following Problem: Given Newton formula for the representation of a polynomial $q(x)$ given the values $y_j$ of $q(x)$ for $j$ between 0 and 5 $q(x)= \...
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1answer
60 views

FindFormula and Piecewise

The command FindFormula does not give me a right formula for simple data like this: ...
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0answers
28 views

DumpSave and precision of interpolation data

Consider the following prec = 32; x = N[Range[0, 1, 1/10], prec]; f = Interpolation[Transpose@{x, y}]; Then ...
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56 views

Interpolation of data from table

How to do the interpolation of this data, so that I can plot the interpolated functionafter interpolation dat1 = Import["newdel(0.5).txt", "Table"] The entries ...
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1answer
56 views

How to address the domain of an outputed interpolating function

I am solving a system of ODEs with DSolve, which returns the results as interpolating functions. The solver always stops after some finite time because of resolution issues, so the domain of the ...
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66 views

How to remove unnecessary filling in ListPlot3D [duplicate]

I have the XYZ data points of this link (also here). If I plot this data ...
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1answer
61 views

Smooth plot of coarsely spaced table values [closed]

In a simpler first case I plotted reasonably spaced (stability) contours by selecting a sequence of k values, ...
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2answers
364 views

Derivative of an interpolated function

I am trying to take the derivative of an interpolated function. I am given the function values and the derivatives at some irregular points. Here is my minimal working example to reproduce the error: ...
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43 views

What is causing this error in the Interpolation function?

I am using trying to understand someone else's code in Mathematica for the Finite Difference Method, except I changed a few values, but none of the code itself. Everything except for the Interpolation ...
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52 views

Evaluation of Mod of InterpolatingFunction prevents discontinuity processing by Plot

While trying out @MichaelSeifert's answer to Eliminating Discontinuities When Using Mod with NDSolve and Plot for Oscillators, I came across this odd behavior. Depending on how an ...
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1answer
111 views

Creating a numerical table of values and using an interpolation of them to transform pixels in an image by the ImageTransformation command

I am trying to carry out point "Implementing Map" on this paper Interstellar wormholes however I am using my own equations not those given (only the same method). I have generated a list of values ...
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1answer
106 views

Creating a numerical table of values from an interpolating function resulting from NDSolve [closed]

I am trying to carry out point "Implementing Map" on this paper Interstellar wormholes however I am using my own equations not those given (only the same method). Part 1 I am trying to create a ...
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2answers
117 views

Bug in VectorFieldPlot[] with InterpolatingFunction[]?

Bug introduced in 11.3 or earlier and persisting through 11.3.0 or later While looking at How do I Plot a Divergence?, I thought to suggest the following as a solution to the OP's problem (where <...
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3answers
84 views

Merge pairs in a list that have the same 1st element by averaging the the 2nd elements

I'm trying to do interpolation on a large list of data of the format {{x1, y1}, {x2, y2}, {x3, y3}, ..., {xn, yn}} that is exported from a simulation. ...
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3answers
90 views

Pass arguments to a function within a function within a function

I want to perform an integration of f[w,t,kx,ky] over t for several different functions f. ...
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2answers
84 views

Solve from interpolation function

I have the following list and its interpolating finction x1: point={{0., 0.}, {0.2, 1.}, {0.25, 1.5}, {0.3, 1.}, {0.5, 0.}};x1 = Interpolation[point] I would ...
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80 views

Why do some uses of PropertyList crash the kernel?

Bug introduced in 10.1.0 or earlier and persisting through 12.0.0 or later A support case with the identification [CASE:4222617] was created. While looking at the question How to evaluate the "...
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2answers
89 views

How to evaluate the “Domain” of a Parametric Function?

In a simple example I try to calculate the time the solution x[t] passes a second time x[t]==1. ...
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2answers
256 views

Complex continuation of an interpolated function

Context I have a complicated real function defined implicitly by a series of imbricated numerical integration. I need to make a continuation of this function for a complex variable which is easily ...
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1answer
87 views

NDSolve and interpolating function

What could possibly went wrong in my code? Basically, I am solving the differential equation $\textbf{ode}$ using $\textbf{NDSolve}$. But mathematica says, NDSolve::mxst: Maximum number of 10000 steps ...
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Why do I keep getting an interpolation error?

Whenever I run this code, it does not seem to be evaluating anything past the Evecs. There are other definitions/parameters involved in running the code. I am just not sure why it keeps saying "first ...
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1answer
33 views

How to close the contourplot3D from top?

I received a very nice solution by Chip Hurst to make my 3DContourPlots smooth and closed in here. Now I have another problem that is simpler but I still want to know the ideas of the others. The data ...
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24 views

Plotting 3D points with function as contour

so I have a grid of points in 2D $(x_i, y_i)$, and a function $f(x_i,y_i)$. I plotted them together like this: -- Now I would like to do the same with a grid of 3D points $(x_i, y_i,z_i)$ and a ...
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35 views

Interpolation of a list defined on a region

I have a three-dimensional table (each element has the form { x, y, f( x, y ) }), and the x, y coordinates spans a region of a parallelogram. If I do a list contour plot of the data, it gives the ...
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1answer
90 views

Approximating decay rate of an amplitude and frequency of an oscillating function

I have an InterpolatingFunction constructed from a discrete set of values obtained by numerical methods. Let's denote it $f(x)$. The function demonstrates an ...
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2answers
108 views

Interpolator surface

Writing: ...
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1answer
71 views

Understanding Energy Function [closed]

I am trying to implement as rigid as possible mesh interpolation solution provided in this article called "As-Rigid-As-Possible Surface Morphing" http://citeseerx.ist.psu.edu/viewdoc/download?doi=10....
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1answer
125 views

Recycling solutions of multidimensional NDSolve

Dear wolfram community, I hope my problem is clear and easy to solve. I have already solved the following heat equation over a domain: ...