A random walk is a mathematical formalization of a path that consists in a succession of random steps. A random walk can be a Markov chain or process; it can be on a graph or a group. Random walks can model randomized processes, in fields such as: ecology, economics, psychology, computer science, physics, chemistry, and biology.
Questions tagged [random-walk]
248 questions
0
votes
1 answer
How can I create a random walk with elements of a dataframe in R?
Good evening,
I have a dataframe with 100 rows and the column headers are ID, x-coordinate and y-coordinate:
ID
X
Y
1
0.1
0.1
2
0.2
0.2
and so on. I would now like to simulate a random walk between these 100 points, but do not know how…
Chocolate173
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- 4
0
votes
1 answer
Error in list index when converting from R to python
I'm trying to convert my R code
set.seed(2021)
startn <- 10
j <- 1
maxj <- 10^5
n <- startn
time <- 0
while (n[j] > 0 & j < maxj){
time[j+1] <- time[j] + rexp(1, rate=2*n[j]^2/5)
n[j+1] <- n[j] + sample(c(-1,1),1)
j <- j+1
…
user309575
- 41
- 5
0
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2 answers
Simulating a Random Walk with a drift (using a for loop)
I am trying to build a simulation of a random walk process with a drift using a loop, however, I am not able to get any outputs and instead I get a length error (number of items to replace is not a multiple of replacement length) which I can't fully…
Santiago Vallejo
- 3
- 1
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1 answer
Subscript out of bounds, iteration for a bound random walk
I am trying to write a function that generates a random walk bound by the unit sphere, resulting in the last location of the random walk given by a vector. In trying to figure out where my function is breaking, I have tried piecing it out like…
bmoscona
- 15
- 4
0
votes
1 answer
Trying to make a 2-D random walk function, why am I getting "unsupported operand type(s) for +: 'float' and 'NoneType'" error?
Here I made a 2-D random-walk where the "character" can only move straight up, down, left or right:
import random
import numpy as np
import matplotlib.pyplot as plt
# I define the possible moves at each step of the 2D walk
dirs = np.array( [ [1,0],…
BoyAcc
- 193
- 7
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1 answer
Migration Matrix in a Two-Dimensional Torus-Like Space: create a migration matrix in R
I'm working on a standard problem in random walk in two dimension.
In particular, I'm trying to generate a migration matrix for a toroidal model (Toroidal Transition Matrix) in R.
I have previously posted the same problem here: Transition matrix for…
CafféSospeso
- 1,101
- 3
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- 28
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Random Walk to a Time Series in R
I am trying to answer the following question"
The time series given below gives the price of a dozen eggs in cents, adjusted for inflation. Fit a random walk to the time series egg.ts. What is the SS1PE?
library(tsdl)
eggs.ts <- tsdl[[440]]
I…
hoke9
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- 1
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Possible ways to incorporate topography in a correlated random walk in R?
I was wondering which possibilities there are for incorporating topography in a correlated random walk in R. I have a digital elevation model (DEM) of the study area. I would like for my random walk to avoid areas with a steep slope.
walk <-…
neòinean
- 39
- 7
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0 answers
Boundary limit for correlated random walk in R
I need to create a boundary for my correlated random walk. This boundary is based on a mask of my study area (raster file). In my for loop I want to add a repeat{} loop which breaks whenever the value of the raster is 0 (and not 1). How would I go…
neòinean
- 39
- 7
0
votes
1 answer
Segmentation fault, while running a Monte-Carlo-random-walk simulation in c++
I am trying to simulate a random walk of 2000 particles, while the one boundary has the ability to make particles bound on that and merely perform a biased step.
There are of course probabilities for binding unbinding etc...
Below I have the whole…
0
votes
3 answers
Random walk Python exercise loop
I am doing python exercise and I can not finish it. I need to a create array and fill it 25 numbers, every number will be the sum of previous one and the value drawn from the set (-5, 5).
import numpy as np
import random
def prog_list(mylist):
…
Coya
- 13
- 3
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1 answer
How does one sample a random walk on a circle with a Gaussian step size in R or Python?
I am trying to obtain samples of a random walk on a circle that takes steps according to N(0, \sigma). To do this for a discrete random walk one calculates the cumulative sum of {+1,-1} coin tosses and then does mod the number of states on the…
hawk.q852
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- 2
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Extraction of data from a plot
Is it possible to extract data from a plot - for example when having the plot of a random walk, is it possible to quantify the amplitudes of fluctuations etc just because of the plot.
Calculator123
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How to get the min and max of a minimum range, along with the min and max of a maximum range of the same set of numbers
I'm getting a stream of numbers from a random walk, and I'm successfully getting the min and max from that random walk using this code:
const rw = require('random-walk')
const num = new rw
let nums = []
num.on("result", number => {
…
Dshiz
- 3,099
- 3
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- 53
0
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0 answers
Need to create a matrix with an unspecified amount of rows so that a for loop can write values to the matrix
I am modeling the drunkards walk in 2D ( a variation of a random walk which ends if the drunk man falls off a cliff). I need to know if there is any way to create the matrix "walk" without specifying the number of rows initially. I was thinking…
