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Questions tagged [data-fitting]

Data fitting is to fit a line through a data set i.e. a series of data points.

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How do I specify error of Y-variable when fitting with lmfit?

I'm almost new to Python and I'm trying to fit data from college using lmfit. The Y variable has a variable error of 3%. How do I add that error to the fitting process? I am changing from scipy's curve fit and in scipy it was really easy to do so,…
Agustin Bayer
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Find the appropriate polynomial fit for data in Python

Is there a function or library in Python to automatically compute the best polynomial fit for a set of data points? I am not really interested in the ML use case of generalizing to a set of new data, I am just focusing on the data I have. I realize…
Jane Sully
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2D curve fitting in Julia

I have an array Z in Julia which represents an image of a 2D Gaussian function. I.e. Z[i,j] is the height of the Gaussian at pixel i,j. I would like to determine the parameters of the Gaussian (mean and covariance), presumably by some sort of…
Yly
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How do I 'fit a line' to a cluster of pixels?

I would like to generate a polynomial 'fit' to the cluster of colored pixels in the image here (The point being that I would like to measure how much that cluster approximates an horizontal line). I thought of using grabit or something similar and…
magnolia1
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choosing step sizes when fitting under python

As you may know, the lmfit module in python is convenient to extend capabilities of scipy.optimize functionnalities. However I don't find something that seems to me necessary: the possibility to choose the step sizes (used for partial derivations,…
Stéphane
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visualize/plot keras metrics with model.fit_generator()

The usage of model.fit_generator() in keras works for me, however I'd like to have a live visualisation of accuracy, loss etc. like it is easily possible with model.fit(). Couldn't find any explanations on how to do that with the…
KatharsisHerbie
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Fit plane to N dimensional points in MATLAB

I have a set of N points in k dimensions as a matrix of size N X k. How can I find the best fitting line through these points? The line will be a plane (hyerpplane) in k dimensions. It will have k coefficients and one bias term. Existing functions…
S_S
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Fitting a power law for extrapolation

I am trying to figure out how to interpolate a function, and I want to be able to extrapolate a small way beyond the interpolation range. There is some background theory which leads me to expect that the behavior for large values of the dependent…
лаетековский чайник
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Fitting data points to an ellipse with its center at the origin using R

I have a question about fitting ellipses to data with the ellipse center at the origin. I have explored two methods that fit ellipses but generate an arbitrary center unless I manipulate the data with some imaginary mirror points. Method#01 This…
ToNoY
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Power Law Fit of cut-off distribution with the poweRlaw package

I am currently trying to find a way to calculate a power-law fit for a cut-off distribution with MLE. The distribution looks as follows: As you can see, I was able to fit the whole distribution (Power-law fit) and also the lower bound (exp-fit)…
Max
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scipy.optimize.curve_fit failing to estimate the covariance

I want to fit data to a Logistic (Sigmoid) function and am getting infinite covariance. I have 2 parameters and suppose I have 5 data points. My data are in the variables xdata and ydata. Here is a code example which generates the exact same…
splinter
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Least squares fit in python for 3d surface

I would like to fit my surface equation to some data. I already tried scipy.optimize.leastsq but as I cannot specify the bounds it gives me an unusable results. I also tried scipy.optimize.least_squares but it gives me an error: ValueError: too many…
UN4
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Fitting un-normalized gaussian in histogram python

I have a dark image (raw format), and plotted the image and distribution of the image. As you can see, there is a peak at 16, please ignore that. I want to fit at gaussian curve through this histogram. I've used this method to fit: Un-normalized…
SjonTeflon
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Fitting a sum to data in Python

Given that the fitting function is of type: I intend to fit such function to the experimental data (x,y=f(x)) that I have. But then I have some doubts: How do I define my fitting function when there's a summation involved? Once the function…
user4587874
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chi-square distribution R

Trying to fit a chi_square distribution using fitdistr() in R. Documentation on this is here (and not very useful to me): https://stat.ethz.ch/R-manual/R-devel/library/MASS/html/fitdistr.html Question 1: chi_df below has the following output: …
Entropy
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