# Tagged Questions

Questions about random number generation and the properties of numbers so generated.

80 views

### RandomPoint fails with a large enough number of points

Bug introduced in 10.2.0 and fixed in 10.3.1. RandomPoint is new in 10.2.0. I have defined a simple ellipsoidal parametric region: ...
112 views

### Random bipartite graphs?

RandomGraph[{n,m}] generates a random graph with $n$ vertices and $m$ edges. I want to generate a random bipartite graph, like ...
162 views

### Smooth initial data

I need something that produce pseudorandom smooth initial data for modelling phase separation equations (Cahn-Hilliard and simular). Generator code for now: ...
62 views

### Generate a simulated covariance matrix

I am working on a problem where one of the input variables is the level of covariance between the entries in a particular matrix. To simulate this problem in Mathematica, I will need to feed my code ...
182 views

### Handling of Temporal Data [closed]

I use a random function of a process which yields a Temporal Data object, I need but do not know how to recuperate the numerical values of the process in a Table from the Temporal Data.
292 views

### How can I create a random symmetric matrix in this way?

The most straight forward way for me to think about is like this: ...
156 views

### Confining/Periodic boundary conditions implementation for 2D Random Walker

I am new to Mathematica, and am having trouble implementing confining boundary conditions for a random walk simulation confining the walker to a pre-defined region (periodic boundary conditions would ...
84 views

### Manipulate a random walk [closed]

For a college project I am manipulating a random walk. I managed to make a walk but in the manipulation every time a step is added the manipulation shows an entirely different walk. I understand why ...
940 views

### Randomly Multiply OR Divide by a Random Number?

I want that Mathematica decides randomly if a given variable, gets multiplied or divided by a random number in a given range. The "naive" idea to just use ...
79 views

### Random phases at each run in a wave superposition [closed]

I need to define a function which generates a random real number between 0 and $2\pi$, as a random phase constant for a wave superposition. The output should be different each time I re-run the code, ...
141 views

### Random Variate generating strange results when using ProbabilityDistribution

I have created a probability distribution that follows a general normal distribution, given by: $$\frac{b *e^{-\left(\frac{\sqrt{(x-u )^2}}{a }\right)^{b }}}{2 a \Gamma \left(\frac{1}{b }\right)}$$...
103 views

### How to use a random number generator as an independent variable in an existing model?

I am relatively new to Mathematica and I need some help regarding how to create a random number generator to be used as an independent variable for a model my group has been working on. Following is ...
125 views

### How to make my fuction return a step count

I am new to mathematica, and I have this 3d random walker program which runs with a fixed (given) amount of steps. What I want it to do is to run forever but stop when two walkers collide (aka have ...
208 views

### How to generate random natural numbers in $[1, \infty)$? [closed]

Functions like RandomInteger draw random variates from a finite range. Can one also obtain random natural numbers in case the range extends from 1 to infinity? If ...
259 views

### How to generate a random pulsar graph between two points?

I am going crazy trying to create this. I am trying to create a pulsar graph that starts and ends on two points that have the same y smoothly along the x axis. The pulsar should have random valleys ...
138 views

### Find random $n$ combinations of values with a given sum

This problem is described in the related StackOverflow question: Find all combinations of coins when given some dollar value. I would like generate a list of $n$ combinations of values that sum up to ...
68 views

### How to solve an equation system whose equations are based on Mod[x,y]

I'm trying to find the parameters of a specific linear congruential generator (pseudo random number generator) based on a list of the first five numbers generated by it. The list is this one: ...
102 views

### Generate $n$ randomly oriented non-intersecting cylinders with fixed radius and length

This post is in reference to the previous question here. How could I adapt the solution given to have the following constraints: fixed radius, fixed length, number of cylinders, and within a ...
118 views

### ParallelTable and Random

Each time I execute the following code it generates the same cylinders with the same format. ...
71 views

### Why doesn't RandomChoice work here? [closed]

I was using RandomChoice to run a simulation to test the probability that picking 4 marbles out of a bag containing 3 red and 7 blue marbles you get 2 red and 2 ...
147 views

### Extending a list

I have a range of n integers (always starting at 1) which are 1 apart, f.e. Range[10], Range[17] or ...
250 views

### generating randomly oriented non-intersecting cylinders

I could not find anything relevant with "googling" (only this) I can create a set of randomly oriented cylinders (code found here) ...
128 views

### how to find circles that intersect a square

I use the following (based on ideas and functions I got as ansers in [1], [2] by, repsectively, @ybeltukov and @J.M.) in order to find random circles with centers inside a unit square that intersect ...
122 views

### Hermitian Matrix

From Derbyshire's Prime Obsession, I would like to get the Mathematica code to generate a Hermitian matrix for evaluation and display. $256 \times 256$ would be nice. Random Normal distribution, ...
62 views

### StringReverse question

I was thinking about how to make this with the StringReverse, but I failed: I have a sequence of (for example) "FDSRTYNHFNKHLIUHG", I wish to reverse, but randomly long sequence reversed from a ...
447 views

### Random character change in a random place

I would like to ask for help in a Random Replace of character. For example: ORANGE and change 1 character randomly (random place and random character from ORANGE) in it into any character of ORANGE, ...
2k views

### Random letters: What is the chance that real words are generated?

Suppose that we are just typing random letters with our keyboards and we include space bar. We don't distinguish between capital and lowercase letters. If we do this for a long time, how many of the ...
268 views

### What will happen, if I don't specify random seed by SeedRandom function?

Suppose I want to run several times of the same code containing RandomReal function, but I don't initialise the random seed. What will happen? I tried, but each ...
86 views

### Random Variable in Recurrence Function

Following the previously published question, I'm looking for the solution of RecurrenceTable with explicit random variable. For example, something like ...
446 views

181 views

### Average positions in a 1D random walk

I wrote this to simulate m random walks of n steps ...
215 views

### Programming a 2D random walk

I have these functions Randomwalk1[n_] :=Accumulate[2*RandomInteger[{0, 1}, n] - 1]; Randomwalk2[n_] := NestList[# + 2*RandomInteger[{0, 1}] - 1 &, 0, n] ...