In R, let’s have an array and a matrix: a <- array(rep(1:3, each = 4), dim = c(2, 2, 3)) b <- matrix(seq(0, 1, length.out = 6), nrow = 2, ncol = 3) I want to use an function that utilises matrices from a along the 3rd dimension and columns in b as its two… Read More How to perform an operation on a 3D array and a matrix whilst returning a 3D array?

I’m trying to use sapply to create a matrix that contains output from rbeta using different specified alphas and betas obtained from a dataset. I think this should be fairly simple, but I am struggling. Here is some data q1 <- c(27, 104) q2 <- c(25, 121) q3 <- c(29, 114) df <- as.data.frame(rbind(q1,q2,q3)) colnames(df)… Read More apply or loop rbeta using different alpha and beta values from a dataframe in R

I want to get the mean of specific columns in a dataframe and store those means in a vector in R. The specific variable names of the columns are stored in a vector. For those specific variables (depends on user input) I want to calculate the mean and store those in a vector, over which… Read More How to get the mean of specific columns in dataframe and store in vector (in R)

I’ve got 3 tibbles in a list that I would like to add a column, for each, with a different value. I found it struggling to do this apart from using the usual for loop (granted, for may well be the best solution in this use case, but I am curious if there’s a clever… Read More One-To-One apply/map in R operations

I have this dataframe: set.seed(42) ## for sake of reproducibility df <- data.frame("time"=c(1:40), "Var1"=sample(1:100, size=40), "Var2"=sample(1:100, size=40), "Var3"=sample(1:100, size=40)) head(df) # time Var1 Var2 Var3 # 1 1 49 3 38 # 2 2 65 21 1 # 3 3 25 2 13 # 4 4 74 58 78 # 5 5 18 10 5… Read More How to add a column next to another consecutively without using loops in R?

I have multiple folders such as "results/[model_name_here]/rasters/" and I’m trying to create multiple objects resulting from a loop of list.files. For example: model_a <- list.files("results/rf/rasters", pattern = "tif$", full.names = TRUE) I was trying to go for a for loop such as models <- c("rf", "brt", "gam", "glm", "mars", "bart", "svm") for(i in models){ i… Read More Create multiple objects resulting from a loop of paste(list.files)