Questions tagged [r]
R is a free, open source programming language and software environment for statistical computing and graphics.
332
questions
-1
votes
0answers
15 views
R simplify nested for loop which removes rows from a global variable
Cross-posted in https://stackoverflow.com/questions/61036376/r-convert-nested-for-to-nested-operator-with-global-variable but I will delete either the SO/CR question which has no useful information
...
2
votes
1answer
30 views
Better filereading and print formating in R
I am a beginner using R and I am trying to solve some simple statistics problems and print the output. The following code takes in two datasets, computes the mean, ...
5
votes
2answers
95 views
Speeding up string splitting in Rcpp/Cpp
I'm looking to speed up an Rcpp function I have written.
The function takes in a string called vcfield, which takes the format od ...
1
vote
1answer
47 views
Statistical sampling from a vector
I have written a function/script to simulate data for sample size estimation. The following code samples from a vector of generated values with varying numbers of sample sizes and then concatenates ...
2
votes
3answers
47 views
Flagging system: Check for changing values in a data frame
I've written the following code to check if a value in a data frame changes. I'm looking at the last 5 values. If there was no change at all I want my code to return 1, if a single one (or multiple) ...
1
vote
0answers
43 views
code plots - spatial data
I am an absolute newcomer in R. For my bachelor thesis I worked with spatial data. I did many plots with the normal "points"-function. I already have my results, but would like to improve my code.
...
4
votes
1answer
71 views
Citymapper API wrapper
As a simple project to tackle during the holidays I've set to write a simple wrapper around Citymapper's api to familiarise with httr, ...
1
vote
0answers
26 views
Extracting English-French cognates from a messy .txt glossary
After using an online tool to convert a PDF glossary of English-French cognates to a .txt file, I wanted to write a simple script to extract the cognate pairs and save them to a CSV. I could then ...
2
votes
1answer
46 views
R solution to max product in matrix for four adjacent numbers (Euler 11)
Background
This is solution to Problem 11 on Project Euler that is concerned with finding largest product of four adjacent numbers in the provided grid.
Other than solving the problem I was also ...
9
votes
0answers
105 views
Generated Minecraft stone texture in R
I needed a Minecraft-like stone texture, instead of creating it using image editing software I decided to generate one using R.
The idea is to create some noise and stretch it horizontally so the ...
1
vote
0answers
52 views
Is there a cleaner way of writing this dplyr sql server query
This is the first time I am writing R code to access/manipulate and save data. The SQL query I would normally run then save to a spreadsheet, read it into R, save to another sheet then copy and paste ...
0
votes
1answer
28 views
Correctness and Performance of graph plotting on R
Current State:
I have two CSV files, their sample attached below:
FileOutputWithoutBuffer-Metrics.csv
...
1
vote
1answer
91 views
R: Optimize algorithm speed that estimates hourly temperature and relative humidity
I built an algorithm to estimate real-time temperature and humidity values based on daily values of the same variables. The algorithm works, however the speed with which it processes the information ...
1
vote
1answer
57 views
Computing features over the same dataframe
The following code computes three different features over the same dataset. I'm not sure if the filter_by_day_segment function can be made tidy or there's a more ...
2
votes
1answer
66 views
Dictionary function for R
I'm new to R and have created a dictionary function. A user will input a phrase into a text field and the server will read it and see if there's a match in a back-end data table and if so, output the ...
2
votes
1answer
87 views
Speed up a while loop that conditionally creates a new variable in R
I would like to speed up the following code in R. This is a loop to define new individuals (column newID) when the variable ...
1
vote
1answer
39 views
Filter string with min distance in r
I have the following sample data:
target <- "Stackoverflow"
candidates <- c("Stackflow", "Stackflow", "Stckoverfow")
I would like to filter the string from ...
8
votes
1answer
401 views
Truth table generator for an arbitrary function
Summary: This function generates a truth table for a boolean function of variable number of arguments. The name of the function passed and its arguments are deduced outside of the computable function ...
2
votes
0answers
59 views
Compute angular distances between data points in a matrix
I am having a hard time speeding up a function that I use to compute angular distances between data points in a matrix. More precisely, I want to compute $$\sum_{r=1}^n|\pi - \arccos\left(\frac{(X_{i}-...
1
vote
0answers
170 views
Random Forest model
I am new in machine learning methods and I am trying to use a Random Forest regression. I want to explain the influence of my variables on the variable "one" and I have the following code:
...
6
votes
2answers
134 views
Mandelbrot rendering code in R
I'm trying out a new continuous histogram coloring method for Mandelbrot rendering in R, and since it requires three loops (three passes), each of them doubly nested, there should be a way to ...
4
votes
2answers
79 views
Looping through two lists and randomly aggregating elements to equal an element from another list
I have three datasets, "CV", "FV" and "LA". I have attached reproducible data for all of them. The idea is that some combination of the elements in each column of CV and FV should sum up to equal the ...
10
votes
1answer
137 views
error-specific tryCatch
R doesn't have classed errors, just (for the most part) error and warning, so determining if the error should be caught or ...
3
votes
0answers
106 views
Efficient way to fill 2D matrices by rows in a list using R
I have a list of 2D matrices. Each matrix is filled using the function “fillMatrices”. This function adds a number of individuals to each day 0 in a matrix and updates the columns “a_M”, “b_M” and “...
3
votes
1answer
442 views
Merge dataframes on timestamps and time intervals using data.table in R
I have two dataframes (x and y) that I need to join, conditional on the timestamp in ...
2
votes
2answers
90 views
Generate a large block diagonal covariance matrix with exponential decay
I am implementing Kalman filtering in R. Part of the problem involves generating a really huge error covariance block-diagonal matrix (dim: 18000 rows x 18000 columns = 324,000,000 entries). We denote ...
2
votes
1answer
82 views
Group by consecutive values in first column and second column value
I have a typing log in which rows are grouped by consecutive package_name, and within those groups rows are grouped if they are logged within 180,000 ms from each ...
3
votes
1answer
55 views
dput() concatenated vector with no quotes, separated by commas in R
An oddly specific task - I have a dataframe with columns with values I need to concatenate in order to prepare a query for a website that requires very specific inputs: unquoted strings, separated by ...
1
vote
1answer
61 views
Replace values in R data frame according to values in other data frame
I would like to change row names values from a first data frame if these rows names are present in another data frame, and change it to a corresponding value (defined in the second data frame). I ...
4
votes
1answer
77 views
Generating random sparse matrix
My goal is to generate a large sparse matrix with majority (~99%) zeros and ones. Ideally, I would be working with 10,000 rows and 10,000,000 columns. Additionally, each column is generated as a ...
1
vote
1answer
31 views
Two-Part Hurdle Model Simulation with Bootstrapping
I am running a simulation study where I am using two-part hurdle modeling on different effect sizes. I tried to stream-line my code for the best optimization including foreach loops and ...
2
votes
0answers
71 views
Bias-corrected percentile Bootstrapping Optimization
I have never posted to this forum, but was referred here. I need some help printing key iterations as well as optimizing my code for run time. If someone had some time to help/explain how to correct ...
3
votes
1answer
55 views
Extracting small word parts (quadgrams) from text using R
I would like to extracts small word parts (quadgrams) from text. Example:
hello world
results in:
...
5
votes
1answer
81 views
Manually writing a function matrixpower() in R
Problem 1 - Matrix powers in R
R does not have a built-in command for taking matrix powers.
Write a function matrixpower() with two arguments mat and k ...
2
votes
1answer
56 views
5
votes
1answer
89 views
Passing uint64_t from C++ to R: Hilbert Mapping - xy2d function
I have been working with Rcpp to perform a forward and backward Hilbert Mapping. Below is an implementation based on this code.
My application is in genomics and I may be dealing with enormous ...
4
votes
1answer
46 views
Sample size, P-values (its relationship), and data visualization with plots. ggplot and T test
We know that P-values (within t-test context as an example..) is highly sensitive to sample size. A larger sample will yield a smaller p-value remaining everything else constant. On the other hand, ...
4
votes
3answers
62 views
3
votes
2answers
86 views
Finding values below a threshold
I am wondering if it's possible to avoid looping. I want to make the function faster. The function is to find how many times a particular value is lower in the overall data. For example:
...
0
votes
0answers
68 views
Text2Vec - fit_transform, $transform TF-IDF
I am sorry if this is a wrong place to post a question.
I have two questions:
~ A)
I am trying to do text similarity using TF-IDF cosine similarity. I somehow managed it in the fallowing code, ...
3
votes
1answer
153 views
Discrete event simulation for production defects
I have one machine, which produces parts. In machine_failure_rate% it produces faulty parts which need to be produced again. Thus, we end up with a simple queuing ...
3
votes
1answer
102 views
Plots of prior and posterior distributions for a model
I have an exercise that ask to plot the prior and posterior distribution in the Poisson-Gamma model. I did it (I think it's correct) inspired
in the answer of this question https://stats.stackexchange....
2
votes
1answer
99 views
A faux parser for fdf files
Introduction
If you know what FDF files are, you can skip this section.
PDF files sometimes includes form fields. These fields can be represented as FDF in plain text form, extracted using certain ...
1
vote
1answer
139 views
Using findInterval to assign vector elements to corresponding brackets
The following function receives a vector of positive integers and list of brackets. The function returns a data frame with a logical vector for each bracket indicating whether a given element of a ...
0
votes
1answer
538 views
Calculate decile table with some loop in R
I wrote code which calculates:
Decile threshold for every decile group
Total income in the decile group
Number of persons
Share of decile in total income (%)
Tax
Share of tax (%)
But unfortunately I ...
1
vote
1answer
75 views
Simulating data generating process correctly
My aim is to simulate the following model by means of a Monte Carlo simulation. I wonder if my R code is correct for generating the data.
Could somebody check?
The model:
$$Y = \sum_{j=1}^{100} (...
1
vote
1answer
77 views
Get maximum sequence lengths taking into account the tradeoff of omitted observations
From a data frame d I have to select the longest possible sequences of x. variables.
Example:
...
-1
votes
1answer
54 views
R Regex : Need only numeric figures [closed]
I'm working on R and using regex to keep only numeric figures in a column (I need to keep digits, negative and decimal sign).
Suppose I've a value
...
2
votes
1answer
76 views
dplyr — tidyverse, pipes, correlation, same variable across time “a” “b”
Have a look at this dataset. The"a" and "b" are used to make possible differentiate when the same variable was measured. In this case X1a and X1b access the same variable, but "a" was (suppose..) in ...
1
vote
1answer
357 views
Using dplyr and pipes for logistic regression plotting
I have successfully created a plot of a binomial glm using example data. https://sciences.ucf.edu/biology/d4lab/wp-content/uploads/sites/125/2018/11/parasites.txt
The predictors of the model include ...
