Trouble pulling data from a messy ASCII file...

input <- readLines(textConnection("19 c:/data/WF-100/2008/20080911/trk/20080911.013115.007.17.txt

closeAllConnections()

# parse out the data
f.parse <- function(line){

fileName <- ''
result <- NULL
for (i in input){

# convert to dataframe for 'melt'
result <- as.data.frame(result, stringsAsFactors=FALSE)
names(result) <- c('fileName', 'variable', 'value')
require(reshape)
cast(result, fileName ~ variable, c)

The output I would be looking for would be one row for each data file with
columns for each variable, so using a .csv example with a few variables
would be:
-------------------------------------------------------------------------
File_name,date_written,program_ver,data_file_ver,bin_width
20080911.013115.007.17.txt, 20081121.145730,3.7,3.6,7.5
--------------------------------------------------------------------------
My plan is to create a table with all the data files listed. This would
allow me to find mean/min/max values for different variables,sort by a
certain variable, etc. I am not limiting myself to R, I have seen awk
mentioned before, so that sounds like it is worth looking at to prep the
data.

Hope that helps.





jholtman wrote:

It would be helpful if you could show what the output would be for the
example given.  Exactly what are 'values' and what would be the
'headings'.  As mentioned before, you can use readLines and then parse
the data you want, but something like Perl might be easier, but it is
hard to tell from the mail.

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
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--
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?

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