# Questions tagged [curve-fitting]

For questions about determining parameters for particular functional form based on set of given data points. These points may be the exact values generated from some underlying function or possibly have some additional noise component.

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### scipy exp model fitting: prevent coefficients blowup

I'm trying to fit a few X-Y points that look like exponential. I used the following scipy code: ...
• 23
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### Computing autocorrelation of scalar values

I obtained a list of $r^2_{end-to-end}$ from a Monte Carlo simulation of polymer movement. ...
124 views

### Weights for equidistant samples in power law fitting

I am working on fitting analytical curves to experimental data obtained in real viscoelastic tests (in fact, static creep tests). The setting of the problem is: the experimental data I have is a set ...
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### biexponential fits where exponents are very similar to each other but different than best monoexponential fit

I have some data which consists of an exponential process in time convolved with a gating function. I am fitting the underlying exponential using the least squares method. (I also have experimental ...
239 views

### Find two lines around which points were randomly generated

Given a list of points that were randomly generated around two lines, find two new lines that match the original lines as closely as possible. Here's the function definition: ...
1 vote
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### Fitting gauss-hermite-parametrization to data?

I want to fit this data. I have the following model functions. Classic gaussian: def gauss_model(x, mu, sigma): return np.exp(-0.5*((x-mu)/sigma)**2) And ...
1 vote
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### Parameter estimation simple theory question related to scipy.optimize.curve_fit

It has been a while since I have done some stats, and I have tried to fit a curve using optimize.curve_fit of parameter estimation. I am also interested in the standard deviation of the fitted ...
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1 vote
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### Fitting Implicit Surfaces to Oriented Point Sets

I have a question regarding quadric fit to a set of points and corresponding normals (or equivalently, tangents). Fitting quadric surfaces to point data is well explored. Some works are as follows: ...
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1 vote
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### matlab lsqcurvefit parameter estimation journey

The lsqcurvefit solution in matlab converges at different solutions depending upon the initial guess: Surface represents the error (SSE) between model and data at various combinations of parameters ...
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I have a data set, composed of points $(x_i, y_i)$ for $i=1,N$. I also have a known function $F$, which maps these points $x_i$ to $y_i$ as such $F(x_i, a(x_i),b(x_i)) = y_i$, where $a(x_i)$ and b(... • 163 0 votes 3 answers 248 views ### Choice of solver/software for global optimisation of cheap black-box function with known derivatives I am trying to estimate a few unknown parameters of my continuous non-linear PDAE model (simulated through finite-volume method spatial discretisation, and time-stepping through method-of-lines). I am ... 2 votes 4 answers 4k views ### Fit best polygon to a discrete contour I have a discrete contour represented by a set of points. The contour looks like a polygon but if you zoom you see that the edges are rugged (that's because it was obtained while working on a finite ... • 1,037 4 votes 1 answer 100 views ### Post-processing the noisy results of numerical simulation I have the following curve, which is calculated on a large number of points and shows smooth behaviour when viewed from distance. However, the derivative (shown below) exhibits artificial ... • 430 1 vote 2 answers 215 views ### Finding an enclosing parabola for a set of points I am looking for an algorithm that fits a parabola to a set of data points. However, no data point may be below the parabola. All points must be above the parabola. Is there an standard algorithm for ... • 111 1 vote 1 answer 2k views ### Curve fitting for oscillating data This is my first question. I have the following data that I'd like to approximate as a parametric function: \begin{align} y = a + (bx_1 + cx_2 + dx_3 + ex_1x_2 + fx_1x_3 + gx_2x_3 + hx_1x_2x_3 + i)*(... 5 votes 3 answers 2k views ### Fitting with a linear combination of exponentials I want to elaborate on a statement I read in Acton's "Numerical methods that work", paragraph "Exponential fitting", page 252. Computationally we are being asked to fit only the parametersA$and$...
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I am struggling finding pseudo Code for a non-linear fit of the following function: $y = a\, x^b$ Package NLS in R does perform well, but utilizing external software is not practicable in my program ...
I have a one-dimensional set of points, i.e. $(n,y_n), 1\leq n \leq N$. I want to fit them with a linear combination of $k$ rectangular functions in a least-squared-error sense. Each rectangle is ...