在R中导入和rbind具有通用名称的多个csv文件

Question

我有多个CSV文件,其名称中包含4个常用字符.我想知道如何使用相同的常用字符来处理文件.例如,"AM-25"在3个csv文件的名称中是常见的,而"BA-35"在另一个2的名称中是常见的.

文件类似于AM-25.myfiles.2000.csv,AM-25.myfiles.2001.csv,AM-25.myfiles.2002.csv,BA-35.myfiles.2000.csv,BA-35.myfiles .2001.csv,我用这个来读取所有文件:

files <- list.files(path=".", pattern="xyz+.csv", all.files = FALSE,full.names=TRUE )

Answer 1

你在找这样的东西吗？

do.call(rbind, lapply(list.files(path=".", pattern="AM-25"), read.table, header=TRUE, sep=","))

这会将从包含字符"AM-25"的csv文件中读取的矩阵组合在一起.read.table根据您的csv文件,参数可能会有所不同.

编辑

我希望这适用于您不知道目录中所有可能的五个字母前缀的文件名的情况:

##Get all different first five letter strings for all cvs files in directory "."                                                                                                                                                                                           
file.prefixes <- unique(sapply(list.files(path=".", pattern="*.csv"), substr, 1,5))

##Group all matching file names according to file.prefixes into a list                                                                                                                                                                                                     
file.list <- lapply(file.prefixes, function(x)list.files(pattern=paste("^",x,".*.csv",sep=""), path="."))
names(file.list) <- file.prefixes ##just for convenience                                                                                                                                                                                                                   

##parse all csv files in file.list, create a list of lists containing all tables for each prefix                                                                                                                                                                           
tables <- lapply(file.list, function(filenames)lapply(filenames, function(file)read.table(file, header=TRUE)))

##for each prefix, rbind the tables. Result is a list of length being length(file.prefixes)                                                                                                                                                                                
##  each containing a matrix with the combined data parsed from the files that match the prefix                                                                                                                                                                            
joined.tables <- lapply(tables, function(t)do.call(rbind, t))

##Save tables to files                                                                                                                                                                                                                                                     
for (prefix in names(joined.tables))write.table(joined.tables[[prefix]], paste(prefix, ".csv", sep=""))