Question

如何下载网页内容并查找其中列有特定扩展名的所有文件。然后下载所有这些。例如，我想从以下网页下载所有netcdf文件（扩展名为* .nc4）： https://data.giss.nasa.gov/impacts/agmipcf/agmerra/

我被建议查看Rcurl包但无法找到如何执行此操作。

Answer 1

library(stringr)

# Get the context of the page
thepage = readLines('https://data.giss.nasa.gov/impacts/agmipcf/agmerra/')

# Find the lines that contain the names for netcdf files
nc4.lines <- grep('*.nc4', thepage) 

# Subset the original dataset leaving only those lines
thepage <- thepage[nc4.lines]

#extract the file names
str.loc <- str_locate(thepage,'A.*nc4?"')

#substring
file.list <- substring(thepage,str.loc[,1], str.loc[,2]-1)

# download all files
for ( ifile in file.list){
 download.file(paste0("https://data.giss.nasa.gov/impacts/agmipcf/agmerra/",
                      ifile),
               destfile=ifile, method="libcurl")

从网站下载具有特定扩展名的文件

1 个答案: