Questions tagged [gaussian]

For issues related to any of the uses of the Gaussian function. Don't forget to add additional tags to clarify the context.

The graph of a Gaussian is a characteristic symmetric "bell curve" shape that quickly falls off towards plus/minus infinity. The 1-D Gaussian is defined as (taken from wikipedia):

gaussian function from wikipedia

The parameter a is the height of the curve's peak, b is the position of the centre of the peak, and c controls the width of the "bell".

In multiple dimensions, the Gaussian is defined as the product of 1D curves along each dimension.

Gaussian functions are widely used in statistics where they describe the normal distributions, in signal processing where they serve to define Gaussian filters, in image processing where two-dimensional Gaussians are used for Gaussian blurs, in mathematics and physics where they are used to solve heat equations and diffusion equations, to formulate the propagation of optical beams (Gaussian beams), to from a basis set of wavefunctions, to define the Weierstrass transform, and many more.

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one Dimensional gauss convolution function in Matlab

I am trying to write a function that returns a one dimentional gauss filter. the function took sigma as a parameter. The problem is that the function returns the same array for all sigmas. function gaussFilter=gauss(sigma) width = 3 * sigma; …
Hani
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Eclipse gives error when using GaussianBlur with OpenCV for Android

I posted a little part of my code, cause i keep getting a strange error that I can't seem to get rid of. The problem can be found on this line: Imgproc.GaussianBlur(mGray, mGray, new Size (5,5), 2.2, 2); public Mat onCameraFrame(Mat inputFrame) { …
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How to calculate derivative of multivariate normal probability density function

Is there any built in function calculating the value of a gradient of multivariate normal probability density function for a given point? Edit: found this how to evaluate derivative of function in matlab? but that is not what I am looking…
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OpenCV: color extraction based on Gaussian mixture model

I am trying to use opencv EM algorithm to do color extraction.I am using the following code based on example in opencv documentation: cv::Mat capturedFrame ( height, width, CV_8UC3 ); int i, j; int nsamples = 1000; cv::Mat samples ( nsamples, 2,…
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Integration in Mathematica

I would like to get a different solution to a problem I have solved "symbolically" and through a little simulation. Now, I would like to know how could I have got the integration directly using Mathematica. Please consider a target represented by a…
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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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how to generate gaussian pseudo random numbers in c for a given mean and variance?

I have a code here which generates random numbers having a mean 0f 1 and std deviation of 0.5. but how do i modify this code so that i can denerate gaussian random numbers of any given mean and variance? #include #include…
Divya
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Gaussian Filter on a vector in Matlab

I have a n-dimensional vector (1xn dataset, and it is not image data), and I want to apply a Gaussian filter to it. I have the Image Processing Toolkit, and a few others (ask if you need a list). Presumably I can make the hsize parameter of the…
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Gaussian Elimination in Java

I was trying to implement a Matrix.class to learn some Java. Right now, I have some difficulties with a method that should return the matrix after Gaussian elimination which will be used to find the inverse of a matrix later on. Here is what I came…
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Using Gaussian Mixture for 1D array in python sklearn

I would like to use a Gaussian mixture model to return something like the image below except proper Gaussians. I'm attempting to use python sklearn.mixture.GaussianMixture but I have failed. I can treat each peak as though it were the height of a…
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Multiclass classification or regression?

I am trying to train a CNN model to classify images based on their aesthetic score. There are 2,00,000 images and every image is rated by more than 100 subjects. Mean score is calculated and the scores are normalized. The distribution of the…
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Understanding Decay function and its parameters in ElasticSearch

I was reading about decay functions in ElasticSearch in order to promote more recent results If I define decay function as following: "DECAY_FUNCTION": { "FIELD_NAME": { "origin": "2013-09-17", "scale": "10d", "offset":…
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Gaussian Process Posterior (Python)

I have created and sampled a jointly Gaussian prior with mean=0 using the code below: import numpy as np import matplotlib.pyplot as plt from math import pi from scipy.spatial.distance import cdist import scipy.stats as sts x_prior =…
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GaussianMixture initialization using component parameters - sklearn

I want to use sklearn.mixture.GaussianMixture to store a gaussian mixture model so that I can later use it to generate samples or a value at a sample point using score_samples method. Here is an example where the components have the following…
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Implementation of Gaussian Process Regression in Python y(n_samples, n_targets)

I am working on some price data with x = day1, day2, day3,...etc. on day1, I have let's say 15 price points(y), day2, I have 30 price points(y2), and so on. When I read the documentation of Gaussian Process Regression:…
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