similar to: matrix position to list of coordinates

Displaying 20 results from an estimated 20000 matches similar to: "matrix position to list of coordinates"

2020 Sep 24
1
How to use `[` without evaluating the arguments.
Hello R-devel, I am currently attempting to implement an API similar to data.table wherein single bracket subsetting can accept an unquoted expression to be evaluated in the context of my object. A simple example from the data.table package looks like this: DT <- data.table(col1 = c('a', 'b', 'c'), col2 = c('x', 'y', 'z')) DT[col1 ==
2011 Dec 14
2
plot matrix of characters
Hi, I am looking for options to plot the following type of matrices: "A" "B" "C" "D" "A" "A" "C" "C" "A" "A" "A" "C" as a image like this: http://www.phaget4.org/R/image002.jpg
2011 Dec 13
4
sum with dates
How do I sum 15 years to my dataset? original dataset dates val 1 2001-01-12 1.2 2 2001-02-12 1.2 3 2001-03-12 1.2 result dates val 1 2016-01-12 1.2 2 2016-02-12 1.2 3 2016-03-12 1.2
2011 Nov 08
3
lapply to list of variables
Hi Can someone help me with this? How can I apply a function to a list of variables. something like this listvar=list("Monday","Tuesday","Wednesday") func=function(x){x[which(x<=10)]=NA} lapply(listvar, func) were Monday=[213,56,345,33,34,678,444] Tuesday=[213,56,345,33,34,678,444] ... in my case I have a neverending list of vectors. Thanks!
2012 Feb 06
3
Logistic Regression
I am looking for R packages that can make a Logistic Regression model with parameter estimation by Maximum Likelihood Estimation. Many thanks for helping out.
2011 Jul 29
5
HIRHAM netcdf files
Can someone help me out with a "small" problem? I've started using netcdf files recently, and I want to extract the grid id and also the coordinates from a HIRHAM netcdf file. I know how to extract a slice of dataset both in space and in time and I also know the area that this file should cover, however I have no idea regarding the reference for both LAT/LON and RLAT/RLON. I tried
2012 Jan 05
3
save output of print() to txt file
I am looking for other option to write the output of the print command in R I am using sink() to write the R output to a file. This is similar to what I have: > a=c(1:30) > a [1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 > sink("vectorA.txt");print(a);sink() I am looking for othe roptions to save the output of the print()
2006 Aug 18
1
Boxplot Help
Hello R-users and developers, Once again, I'm asking for your help. I can identify outliers in boxplot with this instruction result <- boxplot( Income ~ Sex, col = "lightgray", data=dados) if (length(result$out)) text(result$group, result$out, result$out, pos = 4, col = "red") But I can not identify the outlier's id (variable names) in the boxplot.
2011 Dec 28
3
transparency using plot+points with sp classes
How can I make one point graphics with transparency These are all sp classes: plot(polygons_area,axes=TRUE,asp=1.5,main="Title",xlab="Latitude", ylab="Longitude") points(observations2000,type = "p",pch=21,col="green") points(observation1999,type = "p",pch=21,col="blue") points(reference.points,type =
2006 Dec 10
4
sample "n" random positions from a matrix
Hi there, I have a binary matrix (dim 100x100) filled with values 0 and 1. I need select a record "n" positions of that matrix when values are 1. How can I do that? Thanks for all, Miltinho Brazil --------------------------------- [[alternative HTML version deleted]]
2011 Nov 28
5
window manager interface commands for linux
How can i replicate this in Linux: source(file.choose()) I've tried source(tkgetOpenFile()) but with no luck
2012 Feb 03
3
strftime - Dates from Excel files
Hi I have many excel files were the Date field was not declared as date, so the dates look like this: 1/2/1978 I know that the format is day/month/year How can I make R change this to Date format? If I use strftime, I get wrong dates: dataset=c("1/2/1978") strftime(dataset,"%d/%m/%Y") "19/02/0001" Thanks in advance.
2009 Jul 24
2
Stting non-overlaping text positions
Dear List I am having problems to set text labels in a scatter plot. At some areas dots are close and labels overlap and texts cannot be read. I have too many dots to adjust this manually. Is there any function that will calculate the label offsets to avoid this overlapping problem? Thanks Ana -- Ana Conesa Bioinformatics and Genomics Department Centro de Investigaciones Principe Felipe
2012 Feb 08
4
String position character replacement
Hi, Is there a way to efficiently replace specified indices in a string with another character? For example, if I had a vector of strings such as [1] "hellohowareyoudoing" [2] "imgoodhowareyou" [3] "goodandyou" [4] "yesimgoodijusttoldyou" [5] "ohyesthatsright" and had a list of positions that I want to replace with the character "-"
2024 May 21
1
wrtiteBin in conjunction with seek : the position in the file is not good when writing
? Tue, 21 May 2024 11:29:33 +0200 Laurent Rhelp <laurentRHelp at free.fr> ?????: > pos <- seek(con_in,2,origin="start") > # We have to repeat the command to return the good amount of read > # bytes > print(paste0("pos is not equal to 2, pos = ",pos)) That's because seek() returns the previous position ("before any move", the one that the
2008 Oct 31
4
[ifelse] how to maintain a value from original matrix without probs?
Dear all, I have a matrix with positive and negative values. >From this I would like to produce 2 matrices: 1st - retaining positives and putting NA in other positions 2nd - retaining negatives and putting NA in other positions and then apply rowMeans for both. I am trying to use the function ifelse in the exemplified form: ifelse(A>0,A,NA) but by putting A as a 2nd parameter it
2011 Apr 27
6
Assignments inside lapply
Dear all I would like to ask you if an assignment can be done inside a lapply statement. For example I would like to covert a double nested for loop for (i in c(1:dimx)){ for (j in c(1:dimy)){ Powermap[i,j] <- Pr(c(i,j),c(PRX,PRY),f) } } to something like that: ij<-expand.grid(i=seq(1:dimx),j=(1:dimy)) unlist(lapply(1:nrow(ij),function(rowId) { return
2008 Aug 26
4
sequence with start and stop positions
Hi, I have a vector of start positions, and another vector of stop positions, eg start<-c(1,20,50) stop<-c(7,25,53) Is there a quick way to create a sequence from these vectors? new<-c(1,2,3,4,5,6,7,20,21,22,23,24,25,50,51,52,53) the way Im doing it at the moment is pos<-seq(start[1],stop[1]) for (i in 2:length(start)){ new<-seq(start[i],stop[i]) pos<-c(pos,new) }
2012 Oct 26
1
matrix algebra for constructing a special matrix?
Dear R-users, would it be a better way to construct the matrix below without using any for-loop or model.matrix? preferably with some matrix algebra? Thanks in advance, Carlo Giovanni Camarda ## dimensions m <- 3 n <- 4 mn <- m*n k <- m+n-1 ## with a for-loop X <- matrix(0, mn, k) for(i in 1:n){ wr <- 1:m+(i-1)*m wc <- rev(1:m+(i-1)) where <- cbind(wr,wc)
2010 Jun 03
1
plot polar coordinates
Hi, I'd like to plot in in polar coordinates a line which is given as a vector of lengths and angles. library("plotrix")