【R】Rscript中使用变量控制输入输出的文件名

在R输入输出控制中不可避免地将变量引入输出文件名中，这种输出的文件名在Rscript中应该如何加入变量？

library(ggplot2)
library(dplyr)
library(tidyr)

for (i in 10:21){
    file <- paste("result_", i, sep="") 
    out_file <- paste(file, ".out", sep="")
    out_file2 <- paste(file, ".plot", sep="")
    plot_file <- paste(file, ".pdf", sep="")
    df <- read.table(file, header=FALSE)
    df_spread <- tidyr::spread(df, V3, V1)
    #write.table(df_spread, file=out_file,row.names = FALSE, quote =FALSE, sep="\t")
    df_change <- df %>% 
        group_by(V3) %>%
        mutate(V6 = log2(V1 / V5))
    Title <- df[1,4]
    write.table(df_change, file=out_file2,row.names = FALSE, quote =FALSE, sep="\t")
    plot <- ggplot(df_change, aes(x=V3,y=V6,fill=V2)) + geom_col(position= "dodge") + theme_classic() + theme(axis.text.x = element_text(size = 7),axis.text.y = element_text(size = 7), strip.text = element_text(size=10, color = "black"),axis.title.y = element_text(size=11, color = "black"),  strip.text.y=element_text(size=9, color = "black"),  panel.spacing = unit(0.1, "lines"), panel.grid = element_blank(),legend.text = element_text(size = 8),legend.background = element_blank())+ xlab(Title) + ylab("log2(fold change)") +scale_fill_brewer(palette = "Set3")
    ggsave(file=plot_file,plot,width = 8,height = 4, units = "in")
}

　　这里循环变量i可以使用.paste()函数将变量与前缀后缀组合在一起，形成新的文件名。此处要注意参数“sep=”要加，如果没有间隔就是""。