使用 R 下载压缩数据文件、提取和导入 .csv [英] Using R to download zipped data file, extract, and import .csv

问题描述

我正在尝试使用 R 从网页下载并提取 .csv 文件.

I am trying to download and extract a .csv file from a webpage using R.

此问题与 使用R 下载压缩数据文件，提取和导入数据.

我无法使解决方案起作用，但这可能是由于我使用的网址造成的.

I cannot get the solution to work, but it may be due to the web address i am using.

我正在尝试从 http://data.worldbank.org/下载 .csv 文件国家/地区/英国(在下载数据下拉菜单下)

I am trying to download the .csv files from http://data.worldbank.org/country/united-kingdom (under the download data drop down)

使用上面链接中@Dirk 的解决方案，我试过了

Using @Dirk's solution from the link above, i tried

temp <- tempfile()
download.file("http://api.worldbank.org/v2/en/country/gbr?downloadformat=csv",temp)
con <- unz(temp, "gbr_Country_en_csv_v2.csv")
dat <- read.table(con, header=T, skip=2)
unlink(temp)

我通过查看页面源代码获得了扩展链接，我预计这会导致问题，尽管如果我将其粘贴到地址栏中，它仍然有效.

I got the extended link by looking at the page source code, which I expect is causing the problems, although it works if i paste it into the address bar.

文件以正确的 Gb 下载

The file downloads with the correct Gb

download.file("http://api.worldbank.org/v2/en/country/gbr?downloadformat=csv",temp)
# trying URL 'http://api.worldbank.org/v2/en/country/gbr?downloadformat=csv'
# Content type 'application/zip' length 332358 bytes (324 Kb)
# opened URL
# downloaded 324 Kb

# also tried unzip but get this warning
con <- unzip(temp, "gbr_Country_en_csv_v2.csv")
# Warning message:
# In unzip(temp, "gbr_Country_en_csv_v2.csv") :
# requested file not found in the zip file

但这些是我手动下载时的文件名.

But these are the file names when i manually download them.

如果我出错了，我将不胜感激，谢谢

I'd appreciate some help with where i am going wrong , thanks

我使用的是 Windows 8，R 版本 3.1.0

I am using Windows 8, R version 3.1.0

推荐答案

为了让你的数据下载和解压，你需要设置mode="wb"

In order to get your data to download and uncompress, you need to set mode="wb"

download.file("...",temp, mode="wb")
unzip(temp, "gbr_Country_en_csv_v2.csv")
dd <- read.table("gbr_Country_en_csv_v2.csv", sep=",",skip=2, header=T)

看起来默认是w"，它假设一个文本文件.如果它是一个普通的 csv 文件，那就没问题了.但由于它是压缩的，它是一个二进制文件，因此是wb".没有wb"部分，您根本无法打开压缩包.

It looks like the default is "w" which assumes a text files. If it was a plain csv file this would be fine. But since it's compressed, it's a binary file, hence the "wb". Without the "wb" part, you can't open the zip at all.

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