Questions tagged [r]
R is a language and environment for statistical computing and graphics that provides a wide variety of statistical (linear and nonlinear modelling, classical statistical tests, time-series analysis, classification, clustering, ...) and graphical techniques and is highly extensible. (Questions about problems and bugs encountered when using R belong on the R-help mailing list (https://stat.ethz.ch/mailman/listinfo/r-help).)
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Guidelines for image detection model for statis sample
I have 20,000 plus images of art (paintings, sculptures, jars, etc). My goal is creating a computer vision model that, from an input (image), identifies the exact same piece of art and returns its id, ...
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Unable to decipher the error in Anderson-Darling estimation code in R
I just ran the code in R, which estimates some parameters using Anderson-Darling estimation method. The code is given in the appendix of the Habib-Khalil paper.
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Simulating a dataset from model output when model includes multiple binary deviation-coded variables
I am trying to simulate data using parameters from a glmer() model output. The model, which comes from a published paper, is as follows: DV ~ 1 + group* sex *verb type + trial number + (1 |participant)...
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Doubt of wavelets about the return of comand plot() of package Wavethresh in R language
I take a plot of father wavelet with this code
library(wavethresh)
y <- c(1,1,7,9,2,8,8,6)
ywd <- wd(y, filter.number=1, family='DaubExPhase')
plot(ywd)
But ...
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Numerical Method for Multivariate Inversion Formula
For my research, I need to evaluate the density of a random vector $\boldsymbol{X} \in \mathbb{R}^p$ using the multivariate inversion formula. Let the density function of $\boldsymbol{X}$ be $f (\...
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Solve discontinuous ODE with lsode
I am trying to solve a discontinuous ODE using the lsode solver. I tried setting the t_crit parameter to specify the time where the discontinuity is present, but it ...
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How to initialize Eigen C++ parameters within for-loop? [closed]
I am new to Eigen C++ programming. I am trying to create an Rcpp function to call from R. The function takes a list of matrices (Xlst), and two lists of vectors (ylst and smwlst). In each for-loop ...
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Getting gradient from voxel, is it possible and how?
The R package rmarchingcubes implements a marching cubes algorithm. Given a voxel contructed from a function defining an isosurface, it returns a 3d mesh with some vertex normals. When I plot this ...
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Finding matrix of a linear transformation using R programing
The full question is:
Let {u1, u2,···, un} and {x1, x2,···, xm} be bases for Rn and Rm respectively. Let T:Rn→Rm be the linear transformation whose associated matrix with respect to the above bases is ...
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Efficient multidimensional numerical integration in R and C++
I'm trying to perform a 4-dimensional numerical integration in R using a function I wrote in C++ code which is then sourced in <...
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How are scientific computing workflows faring on Apple's M1 hardware
The initial wave of reviews for Apple's M1 hardware are out, and there's lots of generic benchmarks and data on workflows on professional programs for creative users, but I haven't seen anyone talking ...
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Problem of half-planes intersection
Consider the half-planes $\{x \leqslant 2\}$ and $\{x+y \leqslant 3\}$. These two half-planes are coded with the R package 'rcdd' as follows:
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(Lack of) Availability of Finite-Difference library for simple 2D PDEs
I would like to solve two types of simple 2D problems, namely the stationary heat equation on an L shaped geometry like this:
And also compute the magnetostactic field in an air gap of the following ...
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How to solve for underlying function from discrete data set containing integral of that function
New to Computational Science, I hope I'm on the right exchange network for this question.
I have a time series data set that contains the sum of a source data set representing an exponential decay ...
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2-dimensional Gauss-Hermite quadrature in R
A similar question was asked here and the given answer is perfect for a unidimensional integration.
I need to make bidimensional integration in R with a Gauss-Hermite quadrature:
$$\int_{R^2} h(p1,p2)...
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