Fitting 1-D curve to data points, minimizing pre-defined error/loss function.
From wiki:
Curve fitting is the process of constructing a curve, or mathematical function, that has the best fit to a series of data points.
Questions tagged [curve-fitting]
3428 questions
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image analysis curve fitting
I have a bunch of images like this one:
The corresponding data is not available. I need to automatically retrieve about 100 points (regularly x-spaced) on the blue curve. All curves are very similar, so I need at least 1 pixel precision, but…
Dr. Goulu
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Using OpenCV fitEllipse() for circle fitting
Is it valid to use OpenCV fitEllipse for circle fitting.
fitEllipse() returns cv::RotatedRect how about averaging width and height to get fitted circle radius?
krzych
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How to correctly include uncertainties in fitting with python
I am trying to fit some data points with y uncertainties in python. The data are labeled in python as x,y and yerr.
I need to do a linear fit on that data in loglog scale. As a reference if the fit results are properly, i compare the python results…
user1579900
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2 answers
How to use Java Math Commons CurveFitter?
How do I use Math Commons CurveFitter to fit a function to a set of data? I was told to use CurveFitter with LevenbergMarquardtOptimizer and ParametricUnivariateFunction, but I don't know what to write in the ParametricUnivariateFunction gradient…
Italo Maia
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shape-preserving piecewise cubic interpolation for 3D curve in python
I have a curve in 3D space. I want to use a shape-preserving piecewise cubic interpolation on it similar to pchip in matlab. I researched functions provided in scipy.interpolate, e.g. interp2d, but the functions work for some curve structures and…
Nader
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5 answers
Gaussian fit in C#
In a project I'm working on I need to obtain a Gaussian fit from a set of points - needing mean and variance for some processing, and possibly an error degree (or accuracy level) to let me figure out if the set of points really have a normal…
Antonio
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numpy polynomial.Polynomial.fit() gives different coefficients than polynomial.polyfit()
I do not understand why polynomial.Polynomial.fit() gives coefficients very different from the expected coefficients :
import numpy as np
x = np.linspace(0, 10, 50)
y = x**2 + 5 * x + 10
print(np.polyfit(x, y,…
manu190466
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Fitting two lines to a set of 2D points
Given a set of 2D points (black dots in the picture) I need to choose two lines to somehow represent those points. I probably need to minimize the sum of squares of [distance of x to the closer of two lines]^2, although if any other metric makes…
Rafał Dowgird
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Image Offset (2D Baseline) Remove in Matlab
I have an image similar to this one:
and want to remove its underlying baseline so that it looks like:
The image is always different, usually has some peaks and has a total absolute offset and a base surface that is tilted/curved/nonlinear.
I was…
nolimits
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Sub-quadratic algorithm for fitting a curve with two lines
The problem is to find the best fit of a real-valued 2D curve (given by the set of points) with a polyline consisting of two lines.
A brute-force approach would be to find the "left" and "right" linear fits for each point of the curve and pick the…
Vahagn
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Curve Fitting 3D data set
The curve-fitting problem for 2D data is well known (LOWESS, etc.) but given a set of 3D data points, how do I fit a 3D curve (eg. a smoothing/regression spline) to this data?
MORE: I'm trying to find a curve, fitting the data provided by vectors…
Jacob
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How to fix "RuntimeWarning: overflow encountered in exp" when curve fitting real data in Scipy?
I'm trying to determine the best model function and parameters to use for real world data. I have several data sets that all exhibit a similar exponential decay and I want to calculate the fitted function parameters for each data set.
The largest…
Dan
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Using SciPy curve_fit to predict post final score
I have a post, and I need to predict the final score as close as I can.
Apparently using curve_fit should do the trick, although I am not really understanding how I should use it.
I have two known values, that I collect 2 minutes after the post is…
G. Ramistella
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Is there a way to make scipy curve_fit deterministic?
Tried using curve_fit (scipy API, for fitting a sigmoid) with fixed seed for numpy, but still the results vary somewhat.
Is there any way to make it deterministic completely?
As requested in the comments, here's a minimal working example:
from…
mbison
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R implementation of Genetic Algorithm for Bass Model
I try to estimate Bass Curves to analyse diffusion of innovation for different groups. Until now I use nlsLM() of the minpack.lm package to estimate the parameter of the curve/to fit the curve. I loop through different starting values to estimate…
JMueller
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