The questions that get asked repeatedly, gathered together in one place. What’s a question every R programmer asks at some point? Add it here! Grab questions from the r-faq tag to get them added ...

Berthold♦

answered Aug 2, 2023 at 17:39

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How-to guide

How to write a good R question with a reproducible example

This article is largely written based on https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example When posting a question to Stack Overflow, you should include a minimal ...

anon

created Aug 28, 2023 at 18:58

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Why Does Trying to Load rJava Keep Resulting in an Error?

I am trying to run r5r for a transit network based analysis. I am using R 4.4.3 in Positron on Fedora 41. Some context for me is that I have a couple years of R underneath my belt, but I am absolutely ...

M--

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Recommended RStan compiler flags for gcc

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AnthonyC

modified Nov 27 at 13:22

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R GEE Error in `contrasts<-`(`tmp`, value = contr.funs[1 + isOF[nn]]) : contrasts can be applied only to factors with 2 or more levels

I got this error when running GEE with unstructured correlation. Error in `contrasts<-`(`*tmp*`, value = contr.funs[1 + isOF[nn]]) : contrasts can be applied only to factors with 2 or more ...

Ben Bolker

230k

modified Nov 27 at 15:37

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Costing according to a schedule using the hesim package. All strategies at all times?

I am trying to produce a partitioned survival model (PSM) using the hesim package. When supplying a dataframe of costs to stateval_tbl(), which is then passed to create_StateVals(), it seems every ...

L Tyrone

8,361

modified Nov 26 at 19:10

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How can I adjust branches that are outside my phylogeny?

I am working on phylogenetic tree manipulation in R, and I'm encountering a visualization issue with one of my trees. A few branches are being drawn with lengths that go past the terminal nodes (tips) ...

Gerardo Manzanarez-Villasana

modified Nov 26 at 21:24

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data.table programming with variable columns

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r2evans

167k

answered 12 hours ago

Answer Accepted

The I(..) portion within env= is used "to escape automatic conversion" (https://rdatatable.gitlab.io/data.table/articles/datatable-programming.html#substitute-variables-and-character-values),...

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r2evans

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Build forest plot for estimate comparison of multiple models using ggplot2. How to add text of CI?

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Allan Cameron

178k

answered Nov 25 at 12:33

Answer

It takes quite a lot of placing of graphical elements to get you from a basic ggplot to a labelled forest plot. Your two-level grouping (model and parameter) also means that whatever output you are ...

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Allan Cameron

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answered Nov 25 at 12:33

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Creating a unique animal identifier using multiple id columns some with missing data [duplicate]

I have a data set of mark-recapture data with the fields species, ear_tag, pit_tag, and sample_id. I need to create a animal_id column so I can identify each unique animal which unfortunately has ...

Reed

modified Nov 24 at 17:40

Answer Accepted

How about grouping by species, ear_tag, and pit_tag, and assign the current group id? Starting with your df with its "animal_id", we can easily reproduce it with: library(dplyr) df <- ...

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r2evans

167k

answered Nov 24 at 17:39

1 vote

1 answer

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R geom_contour_filled date scale

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stefan

130k

modified Nov 20 at 12:07

Answer Accepted

One option would be to pass a function to the labels= argument of the scale to convert the interval boundaries to date labels in your desired format: library(tidyverse) ggplot(predictions) + aes(x =...

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stefan

130k

answered Nov 20 at 11:50

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Flag rows if the time in a column falls within a specified window of another column

I have a dataframe where each row represents a detection of a fish. The fish can be either, Brown Trout (Fish.ID starts with TB_) or Salmon/Parr (Fish.ID starts with TA_). I want to create a new ...

M--

33.6k

modified Nov 14 at 20:12

Answer

Regarding the solutions in the accepted answer, the (now deleted) data.table approach creates multiple intermediate tables, sorts them, and uses foverlaps() which results in wasting 15GB+ of memory ...

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M--

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Given two data frames: df1 = data.frame(CustomerId = c(1:6), Product = c(rep("Toaster", 3), rep("Radio", 3))) df2 = data.frame(CustomerId = c(2, 4, 6), State = c(rep("Alabama&...

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