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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Gaussian Pyramid Out of Bounds

I am trying to write my own codes for Gaussian pyramid using c++. I tried both reduce and expand equations as stated in http://persci.mit.edu/pub_pdfs/pyramid83.pdf, the equation (1) and (2). However, my array index is out of bounds when I am trying…
randomGirl
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Matrix is singular. RCOND = NaN warning in EM step of GMM

In the EM step of GMM, I call a function gaussianND as: pdf(:, j) = gaussianND(unseen_data, mu(j, :), sigma{j}); which evaluates gaussian for all data points for each cluster 'j'. I have 150 data points and 10 clusters. I get an error: "Warning:…
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How to use a gaussian distribution to calculate a random point on a bullseye in java

I've been working on a project and I need to be able to return a point in a square that acts kind of like a bulls-eye. I wanted to make it return a point that would follow a Gaussian distribution, meaning after a lot of generated results we would…
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When using gauss decay score funtion, it always scores 1 on nested elements

For documents like { "_id" : "abc123", "_score" : 3.7613528, "_source" : { "id" : "abc123", "pricePeriods" : [{ "periodTo" : "2016-01-02", "eur" : 1036, "gbp" : 782, "dkk" : 6880, …
ClausP
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Finding sigma of Gaussian

Is there a simple equation which given the area of the shaded part and the mean, gives you the corresponding sigma for a normal distribuion? P.S the shaded part corresponds to the area under the section of the Gaussian curve which lies on the…
ganninu93
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Adapt Gaussian Kernel to discontinuous Spaces

How to adapt the Gaussian Kernel to discontinuous spaces,such as that of strings over a finite alphabet,for which we already have a kernel (say K(s, t)) defined ? The Gaussian Kernel can be stated by : G(x, y) = e^(−(||x−y||^2)/σ^2)
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Gaussian elimination does not eliminate correct terms

for(count = 0; count < max; count ++) { for (row=(count+1); row < max; row++) { for(column = 0; column < max; column ++) { double t = matrix[row][count]/matrix[count][count]; matrix[row][column] =…
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access violation writing location c++ for Gaussian Elimination

I am working on a code for gaussian reduction, but for some reason I am getting the error: Exception thrown at 0x00A9F6DF in Excersise-7-3.exe: 0xC0000005: Access violation writing location 0xFDFDFDFD. at S[h][0] = i; (line 147) I cant seem to…
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Python gaussian fit on simulated gaussian noisy data

I need to interpolate data coming from an instrument using a gaussian fit. To this end I thought about using the curve_fit function from scipy. Since I'd like to test this functionality on fake data before trying it on the instrument I wrote the…
toti08
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Loopless Gaussian mixture model in Matlab

I have several Gaussian distributions and I want to draw different values from all of them at the same time. Since this is basically what a GMM does, I have looked into Matlab GMM implementation (gmrnd) and I have seen that it performs a simple loop…
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MATLAB: Gaussian RV

So... I am working on part b and I haven no idea what this question is asking me to do. Does it want me to plot the actual Q(x) equation graph with part a graphs?
Kevin Lee
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Python multi-gaussian Fitting - ValueError: GMM estimation with 2 components, but got only 1 samples

I have two Gaussian Distributions that I want to fit. As the two distributions can be mixed differently I wanted the fit to be as universal as possible. I found the code below here: Gaussian fit to a histogram data in python: Trust Region v/s…
Ciaran
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Gaussian Elimination Algorithm GE(A[0 . . n − 1, 0 . . n])?

GE(A[0..n-1,0..n]) // Input an n × (n + 1) matrix A[0 . . n − 1, 0 . . n] of real numbers for i = 0 to n − 2 for j = i + 1 to n − 1 for k = i to n A[j, k] = A[j, k] − A[i, k] ∗ A[j, i]/A[i, i] How to compute for its running time…
Gelo
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initial seed for sparse GP regression

I use the sparse Gaussian process for regression from Rasmussen. [http://www.tsc.uc3m.es/~miguel/downloads.php][1] The syntax for predicting the mean is: [~, mu_1, ~, ~, loghyper] = ssgpr_ui(Xtrain, Ytrain, Xtest, Ytest, m); My question is, the…
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Plotting only one side of gaussian in Python using matplotlib and scipy

I have a set of points in the first quadrant that look like a gaussian, and I am trying to fit it using a gaussian in python and my code is as follows: import pylab as plb import matplotlib.pyplot as plt from scipy.optimize import curve_fit from…
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