similar to: Summarizing a response variable based on an irregular time period

Hello, I am trying to create a plot often seen in hydrodynamic work than includes a contour plot representing the water speed with arrows pointing in the direction of flow. Does anyone have any idea how I might add arrows based on wf$angle (in the example below) to the plot below? Thanks in advance! Sam library(lattice) speed <- runif(100, 0, 20) wf <- data.frame(speed) wf$width <-

Good Morning, I am trying to create a new column of character strings based on the first two letters in a string in another column. I believe that I need to use some combination of ifelse and grep but I am not totally sure how to combine them. I am not totally sure why the command below isn't working. Obviously it isn't finding anything that matches my criteria but I am not sure why. Any

Hello all, I have not been able to find an answer to this problem. I feel like it might be so simple though that it might not get a response. Suppose I have a dataframe like the one I have copied below (minus the 'calib' column). I wish to create a column like calib where I am subtracting the 'Count' when 'stain' is 'none' from all other 'Count' data for

Hello, I am curious if anyone has had any success with finding a R version of a k-sample Kolmogorov-Smirnov test. Most of the references that I have able to find on this are fairly old and I am wondering if this type of analysis has fallen out of favour. If so, how do people tend to compare distributions when they have more than two? Is it reasonable to pursue an adjusted p-value method. That is,

Hello all, I have a fairly simple data manipulation question. Say I have a dataframe like this: dat <- as.data.frame(runif(7, 3, 5)) dat$cat <- factor(c("1","4","13","1","4","13","13A")) dat runif(7, 3, 5) cat 1 3.880020 1 2 4.062800 4 3 4.828950 13 4 4.761850 1 5 4.716962 4 6

Hello, I am having a little trouble formatting my dates correctly. When I plot something using the following commands, R plots the most recent date on the left of the figure and then earlier date on the right of the figure. Given that English is read from left to right I would like to have the dates on my figure arranged in the same way. I am sure that this is something fairly simple but I was

Hello there, I have a situation where I would like to select the first row of a particular factor for a data frame (data example below). So that is, I would like to select the first entry when the factor1 =A and then the first row when factor1=B etc. I have thousands of entries so I need some general way of doing this. I have a minimal example that should illustrate what I am trying to do. I am

Hello there, I am trying to run an ANOVA model using a non-Standard F ratio. Imagine that the treatments (treatments 1 & 2) are applied to the row not to individual samples. Thus the row is the experimental unit. Therefore my error term in my ANOVA table should be the error associated with with row. The question is how do I check the assumptions of an ANOVA model when I have a non-standard F

Hello, I am attempting to write a script that adds error bars to a barchart. I basing my attempt heavily on the following thread: http://tolstoy.newcastle.edu.au/R/e2/help/06/10/2791.html I can't seem to get around the problem that was discussed in the thread. The following example should illustrate my problem. Sorry about the messy example but I am 1) trying to make it as close as possible

Hello R list, This is a question for anyone who has used the by() command. I would like to perform a regression on a data frame by several factors. Using by() I think that I have able to perform this using the following: > lm.r <- by(master, list(Sectionf=Sectionf, startd=startd), function(x) lm (tot.c ~ starttime, data = x)) So that is, I would like to perform separate regressions for

Hello all, I am having a little trouble working with "strptime" and I was hoping someone might be able to give me a hand. I have an instrument that outputs an ordinal date and time in two columns something like this: day.hour min.sec 1 12525 2050 2 12518 2029 3 12524 2023 4 12524 2028 5 12507 2035 Now the problem I am having is converting these numbers

Hello, I'm using R to run a acoustic analysis software called Seewave. I ask the code to extract a list of variables from my recording, and the program give ONE table for each of these. The tables consist of a two column data.frame with the time in column 1 and the frequency in column 2. However, for my purpose I need only one column with the time first and the frequency second. I tried

Hi, I have a data matrix with 13 columns and 55 rows. First coulmn is year and other are monthly values for 55 years. Now i want to create a single column of all the values ( i e a single time series column from column 2 to 13 ). Is it the for loop that works here ...how ? or how i can rearrange the data so that it becomes a times series column. hope i made the question clear . thank you,

Dear R-help I am using R version 2.6.2. I am trying to subtract specific values from a larger data frame. I feel this should be straightforward, but I am struggling. I have a dataframe "Bk" as follows: DateTime cumPrecip 01/01/2008 00:00 348 01/01/2008 01:00 348 01/01/2008 02:00 348 01/01/2008 03:00 347 01/01/2008 04:00 348 01/01/2008 05:00 348 01/01/2008 06:00 349

Hello, I am having a problem making use of some data outputted from an instrument in a somewhat weird format. The instrument outputs two columns - one called JulianDay.Hour and one called Minutes.Seconds. I would like to convert these columns into a single column with a time. So I was using substr() and paste to extract that info. This works fine for the JulianDay.Hour column as there are always

Hey I got Icecast2 to work, except that when I try to listen to it, it has this weird sample error where everything is sped up. Any way to fix this? -- ------------------------------------------------ Joe Bowser Program Director CFUR FM 88.7 - UNBC/CNC Campus/Community Radio Suite 7-222, 3333 University Way Prince George, BC V2N 4Z9 Phone: (250) 960-7664 Fax: (250) 960-5995

>> what is in '/usr/bin/dhcpd-update-samba-dns.sh' ? # will receive addresses from this DHCP server. Instructions are found here: # https://wiki.archlinux.org/index.php/Samba_4_Active_Directory_Domain_Controller#DHCP sleep 5 checkvalues() { [ -z "${2}" ] && echo "Error: argument '${1}' requires a parameter." && exit 1 case ${2} in -*) echo

Hi all, Issue: I have two datasets, one is a regular time series (rain gauge) with resolution of 10 minutes. The other one is an irregular time series (link). Now I want to analyze the correlation between these two datasets with linear regression. The regular time series is a data.frame and the irregular time series is a zoo object. Problem: For the irregular time series (link) I want also a 10

Hello, I am having trouble constructing a time series object for my data. This is because the frequency is irregular: one year, there may be only 100 individuals, another 200. There are 100 measurements for every individual. I have the observations in a data frame with the year that they were taken from as a factor. I would like to plot the top 10 mean measurements for each year and connect them

I have uploaded to CRAN a new package named 'its' (Irregular Time-Series). It implements irregular time-series as an S4 class, extending the matrix class, and records the time-stamp of each row in the matrix using POSIX. Print, plot, extraction, append, and related functionality are available. Feedback and suggestions are welcome. Giles Heywood