> # R script to create a dual-histogram ps file from a predict-2nd bychain files.
> 
> # Usage: R --vanilla --quiet --args 'fname1' 'fname2' < bychain2dualhist.r >& R.bychain2dualhist.log
> 
> # input  file:  fname1.by-chain
> # input  file:  fname2.by-chain
> # output file:  fname1.fname2.by-chain.dualhist.pdf
> 
> infile.bychain.suffix      <- ".by-chain"
> outfile.hist.suffix    <- ".by-chain.dualhist"
> 
> # find the fname arguments after --args
> my.args <- commandArgs()
> my.argnum <- which(my.args == "--args")
> fname1 <- NULL
> fname1 <- my.args[my.argnum+1]
> fname2 <- NULL
> fname2 <- my.args[my.argnum+2]
> 
> if (!length(fname1)) {
+     print("Error: expecting --args 'fname1' 'fname2'") 
+     quit() 
+ }
> 
> if (!length(fname2)) {
+     print("Error: expecting --args 'fname1' 'fname2'") 
+     quit() 
+ }
> 
> infile1.prefix <- fname1
> infile2.prefix <- fname2
> outfile.prefix <- paste (fname1, fname2, sep=".")
> 
> infile1.bychain   <- paste (infile1.prefix, infile.bychain.suffix,  sep="")
> infile2.bychain   <- paste (infile2.prefix, infile.bychain.suffix,  sep="")
> outfile.hist.ps   <- paste (outfile.prefix, outfile.hist.suffix,".ps", sep="")
> outfile.hist.pdf  <- paste (outfile.prefix, outfile.hist.suffix,".pdf",sep="")
> 
> 
> bychain1.data <- read.table( infile1.bychain, header=FALSE, as.is=TRUE)
Error in file(file, "r") : unable to open connection
In addition: Warning message: 
cannot open file `fname1.by-chain' 
Execution halted