Question

我在R中写了下面的if语句。它工作正常，但有一个令人讨厌的警告信息，我1）不完全理解，2）想不得到。： - ）

关于1）：它是什么意思

＆＃34;警告消息：关闭未使用的连接3＆＃34;

在这种情况下，数字（3）的含义是什么？谷歌搜索给了我一些指针（How to fix error "closing unused connection"和Warning: closing unused connection n），它们似乎不起作用，但我知道：它可能是我。我究竟做错了什么？下面是我的代码。

谢谢！

桑德

filetype = summary(file(opt$datagwas))$class

if(filetype == "gzfile"){
    cat("\n* The file appears to be gzipped, checking delimiter now...")
    TESTDELIMITER = readLines(opt$datagwas, n = 1)
    cat("\n* Data header looks like this:\n")
    print(TESTDELIMITER)
    if(grepl(",", TESTDELIMITER) == TRUE){
    cat("\n* Data is comma-seperated, loading...\n")
    GWASDATA_RAW = fread(paste0("zcat < ",opt$datagwas), 
    header = TRUE, sep = ",", dec = ".", 
    na.strings = c("", "NA", "na", "Na", "NaN", 
    "Nan", ".","N/A","n/a", "N/a"),
    blank.lines.skip = TRUE)
    } else {
    cat ("\n\n*** ERROR *** Something is rotten in the City of Gotham. The    GWAS data is neither comma, tab, space, nor semicolon delimited. Double     back, please.\n\n", file=stderr()) # print error messages to stder
    }
    } else if(filetype != "gzfile") {
    cat("\n* The file appears not to be gezipped, checking delimiter     now...")
    TESTDELIMITER = readLines(opt$datagwas, n = 1)
    cat("\n* Data header looks like this:\n")
    print(TESTDELIMITER)
    if(grepl(",", TESTDELIMITER) == TRUE){
    cat("\n* Data is comma-seperated, loading...\n")
    GWASDATA_RAW = fread(opt$datagwas, 
    header = TRUE, sep = ",",dec = ".",
    na.strings = c("", "NA", "na", "Na","NaN",
    "Nan", ".","N/A","n/a","N/a"),
    blank.lines.skip = TRUE)
    } else {
    cat ("\n\n*** ERROR *** Something is rotten in the City of Gotham. The     GWAS data is neither comma, tab, space, nor semicolon delimited. Double     back, please.\n\n", file=stderr()) # print error messages to stder
    }
    } else {
    cat ("\n\n*** ERROR *** Something is rotten in the City of Gotham. We     can't determine the file type of the GWAS data. Double back, please.\n\n",     file=stderr()) # print error messages to stder
    }
closeAllConnections()

Answer 1

您应该做的是打开文件一次，并将连接保存为变量。然后，当您使用完毕后，请自行关闭连接。

# Open it
conn <- file(opt$datagwas)

# Extract the information you need
filetype <- summary(conn)$class
TESTDELIMITER <- readLines(conn, n = 1)

# Then close it
close(conn)

# Continue with if-clause, fread, etc as before

您的方法可能会解决此特定情况。但在其他情况下，如果没有正确识别它们，可能会产生数千到数百个未闭合的连接，从而导致性能问题或崩溃。

Answer 2

感谢@mpjdem，我做了必要的修改。

datagwas_connection <- file(opt$datagwas)

filetype <- summary(datagwas_connection)$class

TESTDELIMITER <- readLines(datagwas_connection, n = 1)

close(datagwas_connection)

if(filetype == "gzfile"){ cat("\n* The file appears to be gzipped, checking delimiter now...") cat("\n* Data header looks like this:\n") print(TESTDELIMITER) if(grepl(",", TESTDELIMITER) == TRUE){等等等（代码的其余部分）

这就像一个魅力。再次感谢！

关于关闭未使用的连接如何在R中抑制警告消息？

2 个答案: