[R] sprintf in system command

hi all I am using r (2.15.2) in windows 7 32bit I want to execute an external program from r console. the program is a command line program which needs the following format to start C:/Users/.../dssp-2.0.4-win32.exe -i data_1.txt -o data_1.dssp I used the system

[R] execute an external program in R

Dear all I am using r (2.15.2) under windows 7 32bit. I want to use system command to execute an external program inside a for loop. this program needs the input and output names. since the names will change in the for loop I am not able to use the programs on all the files for (k in 1:10){

[R] For loop on data frame

I am a beginner in R. I wrote a function to read a data frame from a file and then split it into certain number of data frames and write each one of them in a separate txt file. the function is working perfectly for the first four files the it gives me files contain one column of NA values.