从网站下载多个数据表

Question

我正在尝试通过这个阿尔茨海默病数据库读取 R 中的这五个表。解决方案是什么？如果是网络上的 csv 文件，我可以读成read.table，但是你怎么读未定义的表呢？

我要阅读的表格在这里：Link

Answer 1

这是rvest 和xml2 的一种方法：

首先，打开页面并确定相关表格的位置。例如，在 Chrome 中，按 F12，切换到元素选项卡并展开元素，直到将鼠标悬停在元素上时表格突出显示：

右键单击并选择“复制 XPath”：

现在很简单：

library(xml2)
library(rvest)
library(magrittr) #for %>%
url <- "https://www.alzforum.org/mutations/search?genes=&diseases%5B%5D=145&keywords-entry=&keywords=#results"
my_xpath <- '//*[@id="results"]/article/div/table'
table <- read_html(url) %>% html_nodes(xpath = my_xpath) %>% html_table()
table[[1]][1:10,1:4]
#   Mutation                 Clinical Phenotype              Pathogenicity                                                 Neuropathology
#1     A201V None, Parkinson's Disease Dementia        AD : Not Pathogenic                                                Not applicable.
#2     A235V                Alzheimer's Disease AD : Unclear Pathogenicity                                                       Unknown.
#3     D243N                Alzheimer's Disease AD : Unclear Pathogenicity                                                       Unknown.
#4     E246K                Alzheimer's Disease AD : Unclear Pathogenicity                                                       Unknown.
#5     E296K                Alzheimer's Disease AD : Unclear Pathogenicity                                                       Unknown.
#6     P299L                Alzheimer's Disease AD : Unclear Pathogenicity                                                       Unknown.
#7     R468H                               None        AD : Not Pathogenic                                                Not applicable.
#8     A479S                               None        AD : Not Pathogenic                                                Not applicable.
#9     K496Q                Alzheimer's Disease AD : Unclear Pathogenicity One reported carrier of this variant had autopsy-confirmed AD.
#10    A500T                               None        AD : Not Pathogenic                                                Not applicable.

根据需要重复该过程以下载其他表。