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Hello All I, for the life of me, can't figure out to subset my dataframe by my Date field. The field has been formatted as POSIXlt. str(wild) ...... $ Date : POSIXlt, format: "2010-05-28" "2010-05-28" "2010-05-28" ... This doesn't work: test <-subset(wild,ID=="2830" & Date=="2010-08-17") which returns: <0 rows> (or

I've seen a few threads about this, but none that seem to answer my problem I have a list of .txt files in a directory that I am reading into R and row binding together. I am using the following code to do so: # Directory where files are found my.txt.file.directory <- "C:/Jared/Data/Kenya/Wildebeest/Tracking_Data" names.of.txt.files <-

I have a dataframe of animal locations that I need to have in incremental order so that I can calculate the distance traveled between each time step. However, I have identified a few values that don't seem to sort properly. For instance, the last value in the table below should be the first value after sorting, since its time value is '00:01:35'. But, for some reason, it seems to be

I have a series of animals that are being radio-tracked. I have written some code that goes through each animal and calculates the total distance that each animal is traveling. I will need to run these data on a regular basis and want to write the result to a .php webpage file so that the page updates automatically when I re-run the code. I thought I'd be able to use the