Trouble pulling data from a messy ASCII file...
I usually use Unix tools to process really data beforehand (sed, awk), but if you want a pure R solution it is usually possible to kludge something together with scan() working line by line. # read a line # if it contains stuff you aren't interested in, go on to the next line # if it contains one kind of interesting stuff, do X # if it contains another kind of interesting stuff, do Y and so on. I've done this when it was easier than alternative processing (though slower), and found that it worked best for me to read the entire line in as a string, then split it apart later and convert to numeric if appropriate. Sarah
On Wed, Dec 17, 2008 at 2:37 PM, Titan8883 <jplaney at gmail.com> wrote:
Hi all, I am a new graduate student who is also new to R. I am ok with the basics, but the problem I am having right now seems beyond what I can do..so I am looking for advice. I am trying to pull data from flat ASCII files, but they do not have a "nice" structure so a simple "read.table" doesn't work. An example first half of a data file is below: ---------------------------------------------------------------------------------------------- 19 c:/data/WF-100/2008/20080911/trk/20080911.013115.007.17.txt 10 s name of program that wrote this file trkplt name of program that wrote this file 10 GORDON machine that generated this file machine that generated this file 10 3.7 version of program 10 3.6 version of this data file 10 5.81 version of Universal Library 10 20081121.145730 when this file was written 10 Windows_XP operating system used operating system used * * radar characteristics 11 WF-100 11 20000000 A/D rate, samples/second 11 7.5 bin width, m 11 800 nominal PRF, Hz 11 0.25 nominal pulse width, microsec 11 0 tuning, volts 11 3.19779 nominal wave length, cm ----------------------------------------------------------------------------------------------- ..the file goes on from there... How would I go about getting this data into some kind of useful format? This is one of about 1000 files I will need to go through. I would ideally like to get these into a format with each data file as a row with columns for the various values with the description text removed(version of program, file version, tuning volts, etc...). I'm not looking for a cut and paste answer, but perhaps some direction on where I should start. I have only done basic .csv, table, and line inputs up until now. Thanks for any advice
Sarah Goslee http://www.functionaldiversity.org