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Questions tagged [non-uniform-distribution]

24 questions
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10 answers

Java: random integer with non-uniform distribution

How can I create a random integer n in Java, between 1 and k with a "linear descending distribution", i.e. 1 is most likely, 2 is less likely, 3 less likely, ..., k least likely, and the probabilities descend linearly, like this: I know that there…
Leo
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Effective Java Item 47: Know and use your libraries - Flawed random integer method example

In the example Josh gives of the flawed random method that generates a positive random number with a given upper bound n, I don't understand the two of the flaws he states. The method from the book is: private static final Random rnd = new…
Derek Mok
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Implementing Box-Mueller random number generator in C#

From this question: Random number generator which gravitates numbers to any given number in range? I did some research since I've come across such a random number generator before. All I remember was the name "Mueller", so I guess I found it,…
Lasse V. Karlsen
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Random non-uniform distribution with given proportion

I have 3 labels: "A","B","C". I want to generate a random list with 100 elements, 60% of them are "A", 30% are "B", 10% are "C". How can I do this? (I am new in python, hope this question is not too silly.) Edit: My question is slightly different…
xirururu
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Fourier transform in 3 dimensions on a non uniform grid in matlab

I need to calculated a 3D Fourier transform of a structures I have their [x,y,z] coordinates. I thought of interpolating to a uniform grid of the smallest spacing between the points and use fft, but that turned to be impractical in memory, so fft…
user2066183
5
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1 answer

Non-uniform Distributions for Haskell data types

The random package contains a type class Uniform for uniformly distributed types. This works for types like: data Coin = Heads | Tails But let's say I want to model a set of things with a non-uniform distribution, for example by adding the…
theo
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equivalent function to numpy.random.choice in C++

I need your help to solve the following problem: Is there a function in c++/opencv which is equivalent to the following code: np.random.choice(len(vec), samples, p=probabilities[:,0], replace=True) Thanks in advance.
jack
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2D Interpolation irregular grid fortran

How can I implement 2-dimensional interpolation in FORTRAN where the data looks like as shown below. x and y are two co ordinates and z is a value dependent on them x is spaced evenly but y is not uniformly spaced and the maximum value of…
user1117812
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Fill a vector with a specific distribution of nonuniform screen points

I am trying to fill a vector with a specific distribution of nonuniform screen points. These points represent some x and y position on the screen. At some point I am going to draw all of these points on the screen, which should be unevenly…
Spicy Currey
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Random numbers with non-uniform discrete densities

Just wondering what type of algorithm this is, or if there is an easier/more efficient way to go about this: Say we are given a certain probability density, say prob[] = {.1, .15, .25, .05, .45} Group 1 - 10% Group 2 - 15% Group 3 - 25% Group 4 -…
Jared
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Bicubic Interpolation for Non-regular grids?

I am working on a project where I have a set of known measurements (x,y,z,a) and an input (z,a). I need to be able to interpolate the (x,y,z) so that I can get a list of possible (x,y) coordinates from a given z. I was looking at bicubic…
FlyingStreudel
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Why does taking the salted hash of the mod of a hash result in a very non-uniform distribution?

I have a million randomly generated unique IDs. If I do: result = int(hash(id + 'some_salt')) % 1000 Then this seems to result in an even distribution of IDs to some integer between 0 and 999, with each integer having approximately 1000 IDs mapped…
Josh
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How to adjust for non-uniform sampling (log-scale/polar) in Monte Carlo integration?

I am trying to perform Monte Carlo integration of a function, but sample non-uniformly. I need this method to work for both logarithmic scale and for integration in polar coordinates since I will then combine the two and use polar with log-scale…
Marek Matas
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Do the non-uniform distribution scores reduce Redis Sorted Set performance?

I wonder whether the non-uniform distribution scores would reduce Redis Sorted Set performance. There are two random score generation functions, one obeys uniform distribution, and the other obeys a special custom distribution as the following…
da_miao_zi
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Create equally spaced data from sensor data to apply Fast Fourier Transform

I have the following sensor sample data: Time(milliseconds) Data ------------------ ------------------- 0 0.30865225195884705 60 0.14355185627937317 100 -0.16846869885921478…
danishjo
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