Hopefully there is a simple solution to this problem. I process really large 
satellite images in R and, in order to not offend the memory-limitation 
demi-gods, I open each row of the imagery one at a time, process it, write the 
results, and then open the next line. I use readBin() to open each line.  For 
examaple, say I have the following file:

writeBin(1:20,con="desktop/temp.bip",size=2,endian="big")

which I can open using readBin():

readBin("desktop/temp.bip","integer",size=2,endian="big",n=20)

Now I want to open select values from the binary file, not a complete line.  
Say I want to read values 3, 7, and 10, process them, write the result, and 
then read values 4, 5, and 17.  How do I direct readBin to those specific 
values? Thanks.


Jonathan B. Thayn, Ph.D.
Illinois State University
Department of Geography - Geology
200A Felmley Hall
Normal, Illinois 61790-4400

(309) 438-8112
jth...@ilstu.edu
my.ilstu.edu/~jthayn






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