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

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-3
votes
0answers
51 views

Multidimensional Interpolation with 3 independent Variables with modfied data set

I have four column data with first 3 column denoting x,y,z and fourth column energy. x variable is actually angle. Now I want to interpolate over all three indepdent variable (x,y.z) with ...
18
votes
3answers
3k views

Data interpolation and ListContourPlot

I am fairly new to Mathematica and I have two quick questions on using it for a Hydrology and Hydrogeology class. One is about data interpolation and interpolating without any data defined in an area. ...
20
votes
6answers
3k views

Finding the intersection of a curve with an interpolation function

There are no issues trying to find the intersection points of two defined curves. ...
21
votes
4answers
707 views

How to reduce the InterpolatingFunction building overhead?

I want a linear interpolation from the following example list: ...
2
votes
3answers
58 views

InterpolationOrder 2 or more in ListLogLinearPlot

I'm using the function ListLogLinearPlot, but the plot is to square, i would like to have InterpolationOrder 2, but there is not ...
0
votes
1answer
49 views

Interpolating a function of many variables

I am trying to interpolate a function of 5 variables $$f[m,M,k,v,w]$$ by creating a 5D table of $n$ values in each dimension. ...
8
votes
0answers
99 views

How can I smooth a 3D surface generated by RegionBoundary?

I have a set of points that belong to the surface of an object. I would like to approximate a surface to which I can compute the distance. of other points. With the nice code of this post, I was able ...
2
votes
2answers
132 views

Approximation of definite integral by parabolas

This question is related to Trapezoid approximation to definite integral. As promised, I am now asking about how to draw approximation of integrals by parabolas. I tried to modify MarcoB's code, and I ...
0
votes
1answer
228 views

Transforming Sin into Abs[Sin] dynamically [closed]

Is it possible to interpolate a polynomial that approximates Sin, and then be able to manipulate the polynomial or a sample of its points to make sections of the ...
4
votes
0answers
49 views

Multidimensional arbitrary precision spline interpolation on the grid

This question is a generalization of the previous one for multiple dimensions. In the answer to that question an implementation for the clamped spline interpolation for 1D case and arbitrary degree of ...
0
votes
2answers
291 views

Extract X value from corresponding Y value from a List or Transpose [duplicate]

I have a list of X values and Y values separately, and also together with: data=Transpose[{X,Y}] This data is from a chromatogram, and I want to extract the ...
9
votes
2answers
84 views
0
votes
2answers
70 views

Many NSolves to interpolating function

I have an expression of the form: expr = TerribleNumericalFunction[U[p]] == SimpleFunction[p] The Simple function is a ...
12
votes
2answers
298 views

Interpolation on a regular square grid spanning a triangular domain

Context I am trying to identify contours of a function which is sampled on a cartesian grid within an irregular (triangular) region. Here is the data ...
2
votes
1answer
66 views

Calculate the partial vapor pressures of a variable at xB = 0.75 based on the interpolation functions of the data

I'm having troubles in solving an exercise for an assignment in my Chemistry course. Talking about interpolations, I've already have a graph but I need to calculate the partial vapor pressures of ...
9
votes
5answers
307 views

Function for a series of joined slopes

I need a function for a series of joined slopes and my solution feels a bit kludgy. Is there a better way? A list of pairs of transition points and slopes: ...
2
votes
0answers
71 views

Defining a region from combination of data and geometric region

I would like to define a region in (x,y) by combining the region RegionPlot[ ImplicitRegion[ Sqrt[x^2 + y^2] <= 0.99, {{x, 0.01, 0.99}, {y, 0.01, 0.99}}]] ...
5
votes
3answers
209 views

Derivative of contour in ContourPlot

Sorry to bring this question up again, since there are many similar questions on the site. I use to think this is a easy job to do, because for the worst case I can follow the answers on this site. ...
11
votes
3answers
458 views

Subtracting two plots from each other after shifting one

I have the following lists representing energy spectra that need to be subtracted from each other to produce a difference spectrum. ...
5
votes
0answers
66 views

Kernel Crash while using “ValuesOnGrid” method of InterpolatingFunction

I was experiencing some kernel crash while using "ValuesOnGrid" method of an InterpolatingFunction returned by ...
9
votes
2answers
356 views

Interpolating an Antiderivative

I'd like to be able to make InterpolatingFunctions for antiderivatives of functions that can't be integrated symbolically. However, the following code returns ...
0
votes
1answer
49 views

List manipulation performance or how to make independent list copy

I have a task to solve some system of equations with NSolve and print graph of it, depends on parameters. Something like this (maybe it is not a good example and does not always have a solution, but ...
3
votes
2answers
142 views

Interpolation impossible for ListPlot with Missing?

I have a list of data to plot. I would like to plot them with lines but delete some data before plotting and leave the lines disconnected where data is deleted. For example, ...
0
votes
2answers
227 views

Interpolating a ParametricFunction

Original domain of my independent variable t is 0 to 10 nanometers, but in Mathematica (as in most numerical software), it's good idea to solve differential ...
0
votes
0answers
38 views

Extract x-values from InterpolatingFunction object? [duplicate]

Ok, So I have a numerical solution to a differential equation, and I am trying to get the data points out from it. So far, I have only been able to get the y-values with the following code: ...
-1
votes
1answer
53 views

Interpolation curve [closed]

I have a complicated parametric curve which takes too long to integrate, therefore I want to sample points and interpolate to speed up calculations. The curve is: ...
20
votes
4answers
513 views

Arbitrary precision spline interpolation

The current implementation of Interpolation does not allow arbitrary precision spline interpolation. Yu-Sung Chang says here that "it is not hard to implement it ...
3
votes
3answers
286 views

Finding intersections of two parametric curves

I am dealing with the root finding of two parametric data curves (data below). I have already checked Parametric Interpolation of 2D data, which I found useful for plotting, though it is not adequate ...
15
votes
3answers
942 views

Parametric Interpolation of 2D data

I want to create an interpolation through the following 2dim data points: ...
0
votes
0answers
79 views

Interpolation of a NURBS curve

Known that NQ=P where N is the Bspline basis function, Q is the control point that we wish to locate, P is the data points given ( the curve must pass through it) is there any way to modify the "N" ...
9
votes
2answers
174 views

Build an InterpolatingFunction with ElementMeshInterpolation

Suppose you have a function f[t_, x_, y_] := t (1 - x^2 - y^2) defined for {x,y} in ...
1
vote
0answers
144 views

How to write my own interpolation method [duplicate]

I was comparing results of spline interpolation in Mathematica and C++/gsl-library Results of interpolation are different if I use ...
-2
votes
1answer
94 views

Interpolate/extrapolate a gate charge curve from two different curves

Gate charge measured data. I have gate-charge measurement plots and Excel data for two operating points for a power MOSFET. Vds = 60 V, Id = 50 A Vds = 600 V, Id = 8 mA Can I generate a plot with ...
3
votes
2answers
117 views

Solve for x given an interpolation function, y

Given a list of data, lst={{x1,y2},{x2,y2},...,{xn,yn}} and the interpolation function fun, y=Interpolation[lst] which ...
5
votes
1answer
111 views

Intersection of a ListPlot3D surface with a plane

I'm trying to use Mathematica to analyze some physics data from an experiment, more precisely, I have to fit a 2D data series with a one dimension function. At the moment I'm able to load and plot ...
1
vote
0answers
37 views

Using Quantity[] units causes errors in my calculation

I have an interpolation function in which I wish to use actual units. If I perform the calculation normally, it works fine and returns a proper FittedModel. To illustrate my problem, consider the ...
0
votes
0answers
63 views

Polynomial interpolation using Neville's Algorithm

Is there an interpolating function in Mathematica which uses Neville's algorithm? I have written a C++ program to do interpolation using Neville's algorithm and I am getting a small difference ...
1
vote
2answers
59 views

How to generate commands which are very similar?

I have several data sets that I wish to interpolate and integrate like this: ...
8
votes
2answers
113 views

Changing the `ExtrapolationHandler` Function in Any Interpolation

This is a related question to What's inside InterpolatingFunction[{{1., 4.}}, <>]? and Suppress extrapolation of interpolating function in a ContourPlot. When interpolating a set of ...
5
votes
1answer
132 views

Finding minimum fly-by radius between Mars and spacecraft from interpolating function

I've written an interplanetary trajectory solver/plotter that plots the path taken by a spacecraft on an Earth-Mars mission, but have run into a little trouble when the spacecraft actually reaches ...
4
votes
1answer
65 views

Second derivative of SmoothKernelDistribution PDF?

Does anyone know why I can't seem to get a second derivative of this interpolating function f? In this example, h[x] is zero ...
20
votes
5answers
1k views

How to splice together several instances of InterpolatingFunction?

I have a set of InterpolatingFunction returned by NDSolve which are valid over different (but overall continuous) domains. How ...
1
vote
3answers
99 views

2D Interpolation of data file

I hae a datafile with 5 columns of the structure: x_i f(x_i,y_1) f(x_i,y_2) f(x_i,y_3) f(x_i,y_3) f(x_i,y_4) with i = 1 to about 100. Thus there are about ...
2
votes
0answers
47 views
2
votes
0answers
47 views
36
votes
1answer
773 views

What's inside InterpolatingFunction[{{1., 4.}}, <>]?

I'm curious what's inside the InterpolationFunction object? For example: ...
-1
votes
1answer
83 views

Using InterpolatingFunction in equations

I tried to use InterpolatingFunction in another ODE, but it doesn't work, because it seems for Mathematica that 2 functions are unknown instead of one. ...