Questions tagged [random]
Questions about random number generation and the properties of numbers so generated.
920 questions
1
vote
0
answers
56
views
Eigenvectors of GSE with right properties
I encountered a weird problem when trying to study a few properties of eigenvectors of matrices sampled from the Gaussian symplectic ensemble (GSE). I have encountered this while trying to understand ...
3
votes
4
answers
297
views
RandomPoint on discretized surface not working
This used to work before but apparently not in version 14.3
...
0
votes
0
answers
71
views
Construction of RMT Hamiltonian with given potential
It is well known that the Random Matrix Theory (RMT), the potential function for the Gaussian ensembles, is
$V(H) = \frac{1}{2} H^2 \quad \Rightarrow \quad P(H) \propto e^{-\frac{N}{2} \operatorname{...
3
votes
2
answers
151
views
Generate PSD matrices with a condition
There is this highly upvoted but unanswered post at Math.SE. I would like to try some ideas. This requires numerical experiments with Hermitian and positive definite matrices $A$, $B$, and $C$ such ...
0
votes
1
answer
127
views
Fast partial shuffling?
I need a version of partial shuffling of a 2D table of reals tab that works very efficiently for large arrays and, being repeated $N\gg 1$ times, becomes analogous ...
0
votes
0
answers
108
views
Alternative to RandomSample?
Consider the following simple routines:
...
4
votes
0
answers
221
views
Generating random Hamiltonian cycle
I need random Hamiltonian cycles in directed graphs. I guess for me it would be OK to mean by that choosing uniformly randomly from the set of all Hamiltonian cycles. ...
0
votes
0
answers
117
views
Stochastic Differential Equation with delay
Good day to everyone.
I would like to find a solution of a stochastic differential equation that includes some sort of a delay. But the procedures like ...
3
votes
2
answers
241
views
Random Password Generator question
How to generate password
Re the above post. I am a beginner. I wish to know if I can restrict the random words chosen to a specific length.. for e.g. 6-lettered words. The generated word may look like,...
1
vote
2
answers
136
views
Statistical measures for a list of dates
How do I calculate statistical measures such as Mean, Median, StandardDeviation for a list ...
5
votes
1
answer
144
views
Different speed of RandomInteger depending on syntax?
Consider the two commands:
RandomInteger[3, 10^7]; // RepeatedTiming
RandomInteger[{1, 3}, 10^7]; // RepeatedTiming
The first executes by a factor of 3 faster than ...
3
votes
1
answer
246
views
Something faster than RandomReal and RandomInteger?
I am dealing with the code sequentially producing random numbers and using them further for some operations.
The code snippet looks like
...
0
votes
0
answers
24
views
Simulating data from a piecewise pdf occasionally returns an error [duplicate]
In the following code, I generate data from a piecewise PDF. Usually, I get a sample size of ns, but sometimes I get an error message:
Error: RandomVariate::unsdst:...
2
votes
3
answers
195
views
RandomInteger function to create a list of 10 elements with either Red or Yellow color element [closed]
While following the docs on RandomInteger, it seems mostly covering operations on integers.
But RandomInteger should be applied on other data types such as color as well.
Could anyone please suggest ...
10
votes
1
answer
250
views
RandomVariate sometimes returns the input instead of the numbers
Bug introduced in v14.1 and fixed in 14.2.
I have a series of functions that eventually are combined to form a probability distribution function:
...