similar to: Time Series Object

library(zoo) library(chron) t1 <- chron("1/1/2006", "00:00:00") t2 <- chron("1/31/2006", "23:45:00") deltat <- times("00:15:00") tt <- seq(t1, t2, by = times("00:15:00")) d <- sample(33:700, 2976, replace=TRUE) sin.zoo <- zoo(d,tt) #there are ninety six reading in a day d.max <- rollapply(sin.zoo, width=96, FUN=max)

Does anyone know of a test for stationarity of a time series, or like all ordination techniques it is a qualitative assessment of a quantitative result. Books, papers, etc. suggestions welcome. thanks Stephen -- Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and make us feel like gods. We are

NOTE: I will provide data if necessary, but I didn't want clutter everyones mailbox All: I have a time series with level and temperature data for 11 sites for each of three bases. I will have to do this more than once is what I am saying here. OK, The time series are zoo objects with index values in chron format. The problem is that the date and times should be at even 15 min intervals,

I have a time series object with two columns. a <- ts(x, frequency=1/15) I would like to split this into two time series of the same length (they are the same number of observations lined up time for time already). -- Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and make us feel like gods. We are

#this is a daily series of precipitation data. I would like to condense it into weekly means. How can I do this #as a side note I would like to do this same thing to two years worth of fifteen minute interval data and make it into #a series of daily averages (there are 96 readings per day) #is aggregate the right function? or... y <- c(1.23, 0, 0, 0, 0, 0, 0, 0, 0, 0.27, 0, 0.29, 0, 0, 0,

#Is there a way to break the below zoo object into non-NA data frames algorithmically #this is a small example of a much larger problem. #It is really no even necessary to have the continuous chunks #end up as zoo objects but it is important to have them end #up with the index column. #thanks for all of your help in advance, and #if you need anything else please let me know library(zoo) ind.

day<-structure(c(7.7, 7.7, 7.7, 7.7, 7.7, 7.71, 7.7, 7.71, 7.71, 7.7, 7.7, 7.7, 7.7, 7.69, 7.68, 7.68, 7.67, 7.67, 7.67, 7.66, 7.65, 7.65, 7.65, 7.64, 7.64, 7.63, 7.63, 7.63, 7.62, 7.62, 7.62, 7.62, 7.63, 7.63, 7.63, 7.63, 7.63, 7.64, 7.64, 7.65, 7.65, 7.65, 7.66, 7.66, 7.67, 7.67, 7.67, 7.68, 7.68, 7.69, 7.69, 7.69, 7.69, 7.7, 7.7, 7.7, 7.7, 7.7, 7.71, 7.7, 7.7, 7.71, 7.71, 7.7, 7.7, 7.7, 7.7,

Hello, I propose two small changes to spec.pgram to get modest speedup when dealing with input (x) having multiple columns. With plot = FALSE, I commonly see ~10-20% speedup, for a two column input matrix and the speedup increases for more columns with a maximum close to 45%. In the function as it currently exists, only the upper right triangle of pgram is necessary and pgram is not returned by

Solved. I tried to create a minimal example, but my script is too complicated to just cut out lines (too many dependencies). Instead of it, I sketch my idea. I do not say it is the nicest solution, but it works as I wanted. The first five rows of my data-matrix: > data_svd$u[1:5,] [,1] [,2] [,3] [,4] [,5] [,6] [,7] 25.12333 -0.05845695

Is there a way to write and analysis to disk and then reconstruct the whole thing back into an object. wavCWT() #wmtsa package I am running out of memory on my computer and I was wondering if there was a way to iterate through this process (as it is an iterative process anyway- it just stores the whole thing to memory). Or is there a way to set the scale that I want to look at so that wavCWT

plot(1,2, ylab= paste("insects", expression(m^2), sep=" ")) I get insects m^2 I would like m to the 2 what is the problem? -- Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and make us feel like gods. We are mammals, and have not exhausted the annoying little problems of being

RM215.sp <- SpatialPoints(RM215, proj4string=CRS("+proj=longlat +datum=WGS84")) d060101 <- as.POSIXct("2006-01-01", tz="EST") study_seq <- seq(from=d060101, length.out=761, by="days") up.215 <- sunriset(RM215.sp, study_seq, direction="sunrise", POSIXct.out=TRUE) down.215 <- sunriset(RM215.sp, study_seq, direction="sunset",

I am not entirely sure what is going on. I am sure that I am missing something. maptools won't detach... Thanks for all of your help. R 2.11.1 OS Ubuntu 10.04 R --vanilla install.packages("sp", dep=TRUE) Loading required package: reshape Loading required package: plyr Loading required package: grid Loading required package: proto This is vegan 1.17-3 Loading required package:

I am using the function metaMDS with jaccard distances to ordinate a set of constituent by site matrix. I can post this data if it would be helpful, but it is large to include in an email. I can also provide reproducable code if necessary. I would like to get an R^2 value for the axes of the ordination configuration that I get with metaMDS in the vegan package is there a way to do this- is it

I have a suggestion for kernapply for ts objects. When we choose the option circular=F, the returned series don't have the correct dates. The removed dates are all at the beginning instead of half at the beginning and half at the end. It is particularly useful when we need to smooth the series (or remove a trend using a filter) before estimating a model (like in macroeconomics) or simply

These are date and times in the format YYYYMMDDhhmmss. I would like to take this column and make a chron object form them. I have tried a couple of the split family of functions but they need character input here is the data: date.time <- c(19851001001500, 19851001003000, 19851001004500, 19851001010000, 19851001011500, 19851001013000, 19851001014500, 19851001020000, 19851001021500,

#I am putting a test together for an introductory biology class and I would like to put different cross hatching inside of each bar for the bar plot below color <- c("Brightly Colored", "Dull", "Neither") lizards <- c(277, 70, 3) liz.col <- data.frame(color, lizards) qplot(color, lizards, data=liz.col, geom="bar", ylab="Observed Matings",

have a data frame composed of many columns. I would like to hold one column constant and scatter plot it agianst all of the other columns? how do I do this? I have only been able to plot(x) and use indexes to create an entire scatterplot matrix, but not hold one constant. -- Let's not spend our time and resources thinking about things that are so little or so large that all they really do

I have got a data set that is Gross Primary Productivity ~ Total Suspended Solids it is a hyperbola just like: plot(1/c(1:1000)) how do I model this relationship so that I can get all of the neat things that lm gives residuals etc. etc. so that I can see if my eyeball model stands up. Thanks for any help, pointers, or good things to read. -- Stephen Sefick Research Scientist Southeastern

mac osx 10.5.4 R 2.7.1 I have fit a model d<-lm(y~x) with an R^2 of 0.963 but when I issue the command abline(d) the line is below where it ought to be. Looks like the right slope, but not the right intercept. thanks -- Stephen Sefick Research Scientist Southeastern Natural Sciences Academy Let's not spend our time and resources thinking about things that are so little or so large