我实现了以下过程,旨在写入一些文件并在写入完成后在每个文件的末尾打印一条消息:
# Print one file per piaf
output_dir_piafs <- "OUTPUT_dataset_piafs"
unlink(output_dir_piafs, recursive = TRUE, force = TRUE)
dir.create(output_dir_piafs)
for (i in 1:length(lst_sorted)) {
sink() # Generates warnings...
filename <- paste(output_dir_piafs, "/piaf_", i, ".txt", sep="")
sink(file = filename, append = TRUE)
sink(type = "message")
cat(" ", colnames(file1), "\n")
for (j in 1:length(lst_sorted[[i]])) {
cat(j, " ")
lapply( lst_sorted[[i]][[j]],
function(x) {
cat(as.character(x), " ")
}
)
cat("\n")
}
## back to the console
sink()
cat(paste(filename, "done !\n"))
#flush(stdout()) # Tested, no particular effect
}
我的问题是,如果我不在sink()
循环的最开始添加 a ,则标准输出 ( cat(paste(filename, "done !\n"))
) 上的最终写入将无效。另一方面,提早添加sink()
会产生我想避免的警告:
There were 50 or more warnings (use warnings() to see the first 50)
> warnings()
Warning messages:
1: In sink() : no sink to remove
2: In sink() : no sink to remove
3: In sink() : no sink to remove
有没有人知道 sink() 的行为方式和/或如何摆脱这些警告?
注意:我也尝试过try(sink(), silent=TRUE)
,但该silent
选项只能防止错误...