Question

您好我在这里指的是问题 - Downloading multiple files using "download.file" function in R

但我找不到我想要的答案。我想从多个网址下载数据，我使用以下代码：

我正在尝试做类似的事情而且在R中相对较新。以下是我的代码：

temp <- tempfile(pattern = "my", fileext = ".txt")    #my is a vector in YYMM form

masterfile = as.data.frame(NULL)

for(i in 1:length(my)) {

  download.file(url = paste0("http://www2.census.gov/econ/bps/Metro/ma", "my[i]", "c.txt"), destfile = paste0("/Users/shashankrai/GitHub/data-science/homeworks/homework1/","my[i]","c.txt"), mode = wb)

temp <- read.table(paste0("/Users/shashankrai/GitHub/data-science/homeworks/homework1/","my[i]","c.txt"), sep = ",", skip = 3)[, c(1,3,5)]

masterfile <- rbind(masterfile, temp)

}

它引发了以下错误：

卷曲：（3）第44栏中[全局]坏范围

文件错误（文件，“rt”）：无法打开连接

另外：警告信息：

1：在download.file中（url =   paste0（“http://www2.census.gov/econ/bps/Metro/ma”，：下载了   非零退出状态

2：在文件（文件，“rt”）中：无法打开文件   '/Users/shashankrai/GitHub/data-science/homeworks/homework1/my[i]c.txt'：   没有这样的文件或目录

你能告诉我我做错了吗？

我也试过这个：

temp <- tempfile(pattern = "my", fileext = ".txt")

masterfile = as.data.frame(NULL)

for(i in 1:length(my)) {

  download.file(url = paste0("url", "my[i]", "c.txt"), destfile = my[i], mode = wb)

  temp <- read.table(my[i], sep = ",", skip = 3)[, c(1,3,5)]

  masterfile <- rbind(masterfile, temp)

}

Answer 1

没关系。弄清楚了。这是一个最终有效的代码：

masterfile = as.data.frame(NULL)

for(i in 1:length(my)) {

  temp <- tempfile(pattern = "my", fileext = ".txt")

  download.file(url = paste0("http://www2.census.gov/econ/bps/Metro/ma",     my[i], "c.txt"), destfile = temp[i], mode = wb)

  masterfile <- rbind(masterfile, read.table(file = temp[i], sep = ",", skip = 3)[, c(1,3,5)])

}

for循环和下载多个网址

1 个答案: