similar to: Calling a column from a matrix using a variable

Displaying 20 results from an estimated 40000 matches similar to: "Calling a column from a matrix using a variable"

2012 Nov 19
5
help on matrix column removal based on another matrix results
Hi everyone, now I am trying to finish writing the code (I had asked for assistance on subtracting arrays) This is what I what I am running in R: > source("/home/ie/Documents/TTU/GA_Research/GLUE/R-Project/R_GLUE_Example/NSEr.R") NSEr <- function (obs, sim) { {jjh <- (as.vector(obs) - sim)^2 Xjjhs <- apply(Xjjh, 2, sum) Yii <- (obs - mean(obs))^2 Yiis <- apply(Yii, 2,
2018 Nov 21
2
Subsetting row in single column matrix drops names in resulting vector
Hello here. I'm struggling to understand R's subsetting behavior in couple of edge cases - subsetting row in a single column matrix and subsetting column in a single row matrix. I've read R's docs several times and haven't found answer. Consider following example: a = matrix(1:2, nrow = 2, dimnames = list(c("row1", "row2"), c("col1"))) a[1, ] # 1
2018 Nov 21
3
Subsetting row in single column matrix drops names in resulting vector
Hi Rui. Thanks for answer, I'm aware of drop = FALSE option. Unfortunately it doesn't resolve the issue - I'm expecting to get a vector, not a matrix . ??, 21 ????. 2018 ?. ? 20:54, Rui Barradas <ruipbarradas at sapo.pt>: > Hello, > > Use drop = FALSE. > > a[1, , drop = FALSE] > # col1 > #row1 1 > > > Hope this helps, > > Rui Barradas
2012 Jun 12
4
How to index a matrix with different row-number for each column?
here's my question: suppose I have a matrix: mt<-matrix(1:12,ncol=6) now I have a vector vt<-c(1,2,2,2,1,2) which means I want to get: the 1st row for column1; the 2nd row for column2; the 2nd row for column3; the 2nd row for column4; ... that what I want is this vector: 1,4,6,8,9,12 Does anyone know how to do this fast? I know I can use for-loop to travel all columns,but
2018 May 22
1
Bootstrap and average median squared error
Hello, Right! I copied from the OP's question without thinking about it. Corrected would be bootMedianSE <- function(data, indices){ d <- data[indices, ] fit <- rq(crp ~ bmi + glucose, tau = 0.5, data = d) ypred <- predict(fit) y <- d$crp median((y - ypred)^2) } Sorry, rui Barradas On 5/22/2018 11:32 AM, Daniel Nordlund wrote: > On 5/22/2018
2018 May 22
2
Bootstrap and average median squared error
I forgot, you should also set.seed() before calling boot() to make the results reproducible. Rui Barradas On 5/22/2018 10:00 AM, Rui Barradas wrote: > Hello, > > If you want to bootstrap a statistic, I suggest you use base package boot. > You would need the data in a data.frame, see how you could do it. > > > library(boot) > > bootMedianSE <- function(data,
2023 Jun 11
1
Problem with filling dataframe's column
?s 22:54 de 11/06/2023, javad bayat escreveu: > Dear Rui; > Many thanks for your email. I used one of your codes, > "data2$LU[which(data2$Layer == "Level 12")] <- "Park"", and it works > correctly for me. > Actually I need to expand the codes so as to consider all "Levels" in the > "Layer" column. There are more than hundred
2018 May 21
2
Bootstrap and average median squared error
Dear R-experts, I am trying to bootstrap (and average) the median squared error evaluation metric for a robust regression. I can't get it. What is going wrong ? Here is the reproducible example. ############################# install.packages( "quantreg" ) library(quantreg) crp <-c(12,14,13,24,25,34,45,56,25,34,47,44,35,24,53,44,55,46,36,67) bmi
2012 Dec 14
1
Plotting from a matrix, where column 1 is your x value
Hello, I'm very new to R, and have managed to plot xy graphs, but can't seem to plot a matrix properly. The first column is my time points, and the following columns 2-4 are the replicates of my experiment. I've tried using row.names=1 to make the first column the value for that row (whereas before I had 1-31 sequence) and then my 1st column) but I can't work out how to tell it
2018 May 22
0
Bootstrap and average median squared error
Hello, If you want to bootstrap a statistic, I suggest you use base package boot. You would need the data in a data.frame, see how you could do it. library(boot) bootMedianSE <- function(data, indices){ d <- data[indices, ] fit <- rq(crp ~ bmi + glucose, tau = 0.5, data = d) ypred <- predict(fit) y <- d$crp median(y - ypred)^2 } dat <-
2012 Dec 04
3
How to find matching columns in a matrix of lists?
Dear R users, I have a matrix composed of lists: m <- matrix( list(), nrow=1, ncol=3 ) m[[ 1, 1 ]] <- list("A", "B") m[[ 1, 2 ]] <- list("A", "C") m[[ 1, 3 ]] <- list("A", "B") and want to get the sub-matrix where cells contain "B". But m[ , "B" %in% m[ 1, ], drop=F ] as well as m[ , "B"
2012 Jun 07
1
select subrows based on a specific column in a matrix
Hi all, I have a matrix with 10000 rows and 10 columns. The last columns contains another identifiers but the values are not uniques so that I want to generate another matrix with rows with unique values in the last column. If I did tmp<-unique(my_mat$col10) this will give me 8560 unique entries so the ideal matrix will be 8560X10 columns now then. I tried sub_mat<-my_mat[tmp,] but
2013 Apr 18
3
dividing a long column to many short ones by a condition
hello i have a very long column of numbers. i want R to make a new column every time the value changes from zero. example for the column: 90.1194354 87.94788274 80.34744843 64.06080347 30.40173724 0 0 0 0 0 16.28664495 23.88707926 29.31596091 48.85993485 13.02931596 0 0 0 7.600434311 20.62975027 29.31596091 32.5732899 for this example i want to get 3 columns. thanks! [[alternative HTML version
2013 Jan 28
2
centering matrix
? stato filtrato un testo allegato il cui set di caratteri non era indicato... Nome: non disponibile URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20130128/e2b59d9c/attachment.pl>
2018 May 22
0
Bootstrap and average median squared error
On 5/22/2018 2:32 AM, Rui Barradas wrote: > bootMedianSE <- function(data, indices){ > ???? d <- data[indices, ] > ???? fit <- rq(crp ~ bmi + glucose, tau = 0.5, data = d) > ???? ypred <- predict(fit) > ???? y <- d$crp > ???? median(y - ypred)^2 > } since the OP is looking for the "median squared error", shouldn't the final line of the
2023 Jun 11
1
Problem with filling dataframe's column
Dear Rui; Many thanks for your email. I used one of your codes, "data2$LU[which(data2$Layer == "Level 12")] <- "Park"", and it works correctly for me. Actually I need to expand the codes so as to consider all "Levels" in the "Layer" column. There are more than hundred levels in the Layer column. If I use your provided code, I have to write it
2018 May 26
1
Grouping by 3 variable and renaming groups
Hello, Sorry, but I think my first answer is wrong. You probably want something along the lines of sp <- split(priceStore_Grps, priceStore_Grps$StorePC) res <- lapply(seq_along(sp), function(i){ sp[[i]]$StoreID <- paste("Store", i, sep = "_") sp[[i]] }) res <- do.call(rbind, res) row.names(res) <- NULL Hope this helps, Rui Barradas On 5/26/2018
2018 May 22
0
remove rows of a matrix by part of its row name
Hello, Please always cc the list. As for the question, yes, it does. If you want to remove just the ones with exactly 73.1 use the pattern grep("^73\\.1$", etc) Explanation: Beginning of string: ^ End of string: $ Escape special characters: \\ (needed because the period is a special character.) Hope this helps, Rui Barradas On 5/22/2018 12:50 PM, Ahmed Serag wrote: > Thank
2018 May 26
0
Grouping by 3 variable and renaming groups
Hello, See if this is it: priceStore_Grps$StoreID <- paste("Store", seq_len(nrow(priceStore_Grps)), sep = "_") Hope this helps, Rui Barradas On 5/26/2018 2:03 PM, Jeff Reichman wrote: > ALCON > > > > I'm trying to figure out how to rename groups in a data frame after groups > by selected variabels. I am using the dplyr library to group my
2018 May 26
3
Grouping by 3 variable and renaming groups
ALCON I'm trying to figure out how to rename groups in a data frame after groups by selected variabels. I am using the dplyr library to group my data by 3 variables as follows # group by lat (StoreX)/long (StoreY) priceStore <- LapTopSales[,c(4,5,15,16)] priceStore <- priceStore[complete.cases(priceStore), ] # keep only non NA records priceStore_Grps <- priceStore %>%