Hello All:
I am very new to R and am trying to import some (107) text files into R while simultaneously manipulating the data into a structure that I can use.  Below is a description of what I am trying to ultimately accomplish.  However, I find that I am unable to even read one file into R using the read.table function.  I get the following error: 
> test<-read.table("test4.txt")
Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings,  : 
  line 16 did not have 8 elements
 
So, I would like to resolve the error first, and then ultimately accomplish the goal outlined below.  I understand that my ultimate goal may require multiple steps.  I am open to that.


First, a little background:  Data were collected from 107 participants on palm pilots.  Participants were randomly beeped 5 times throughout the day for 5 days resulting in a total of 25 measurement occasions.  Participants responded to beeps only when they were able to (not in class, driving, etc).  Thus, most participants completed far less than 25 measurement occasions.  During each measurement occasion participants responded to 32 questions by moving a slider on a 100 point scale.  The palms recorded the date, time, palm pilot ID number, response to the beep (non-response = -32767), question number, response latency in milliseconds, response to each question, and three addtiional data points of no interest.  The data are arranged in an unstacked (long) text file such that each line contains all of the above information and there are 34 (32 responses plus 2 extra lines of meaningless data) lines per measurement occasion (upto 850 lines of data if all 34 lines are present for all 25 measurment occasions). Below is an example of how the data are arranged.

20080204131646         2        32            560        63  6         0 ""
20080204131646         2        33            152        -1  7         0 ""
20080204150043         2    -32767              0      9999  0     65535 ""
20080204182117         2         1            283        -1  7         0 ""
20080204182117         2         2            838        34  6         0 ""
20080204182117         2         3            266        36  6         0 ""
Year/Month/Day/Time  Palm ID  Response/Q#    Latency  Response  3 meangingless columns    The dataset presented above begins with question 32 of one measurement occasion on Febraury 4, 2008 taken at 13:16:46.  The next line (33) is in the datafile because participants had to click a button to exit the measurement occasion.  You then see the beginning of another measurement occasion (20080204192117) in which the participant did not respond (-32767).  The next measurement occasion begins on the next line which actually starts with response 2 because participants were required to read a screen and click through prior to answering any questions.  Thus, anytime participants simply read an instruction page responses are coded as a -1.  What I would like to do is write code to automatically import these 107 files into R and structure them appropriately while importing them.  Furthermore, I would like for the code to use conditional statements so that whenever it encounters a -32767 it inserts 32 variables (columns) with missing data and whenever it encounters a -1 it deletes that column all together.  I would also like the code to separate the combined year/month/day/time column into 4 separate columns (year, month, day, time).  Finally, I would like the code to stack the 32 responses during each measurement occasion so that I have 32 columns of reponses plus columns for year, month, day, and latency, but leave each measurment occasion unstacked. 

Thanks!

Eric S McKibben
Industrial-Organizational Psychology Graduate Student
Clemson University
Clemson, SC
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