当缺少&lt；tr&gt；标记时，使用rvest R-擦除-前端问题

R - Scraping an HTML table with rvest when there are missing lt;trgt; tags(当缺少lt；trgt；标记时，使用rvest R-擦除HTML表格)

本文介绍了当缺少&lt；tr&gt；标记时，使用rvest R-擦除HTML表格的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在尝试使用rvest从网站上抓取一个HTML表。唯一的问题是，我要清理的表没有<tr>标记，第一行除外。如下所示：

<tr> 
  <td>6/21/2015 9:38 PM</td>
  <td>5311 Lake Park</td>
  <td>UCPD</td>
  <td>African American</td>
  <td>Male</td>
  <td>Subject was causing a disturbance in the area.</td>
  <td>Name checked; no further action</td>
  <td>No</td>
</tr>

  <td>6/21/2015 10:37 PM</td>
  <td>5200 S Blackstone</td>
  <td>UCPD</td>
  <td>African American</td>
  <td>Male</td>
  <td>Subject was observed fighting in the McDonald's parking lot</td>
  <td>Warned; released</td>
  <td>No</td>
</tr>

等等。因此，使用以下代码，我只能将第一行放入我的数据框中：

library(rvest)
mydata <- html_session("https://incidentreports.uchicago.edu/incidentReportArchive.php?startDate=06/01/2015&endDate=06/21/2015") %>%
    html_node("table") %>%
    html_table(header = TRUE, fill=TRUE)

如何更改它以使html_table理解这些行就是行，即使它们没有开始<tr>标记？或者，有没有更好的办法来解决这个问题？

推荐答案

library(rvest)

url_parse<- read_html("https://incidentreports.uchicago.edu/incidentReportArchive.php?startDate=06/01/2015&endDate=06/21/2015") 

col_name<- url_parse %>%
  html_nodes("th") %>%
  html_text()

mydata <- url_parse %>%
  html_nodes("td") %>%
  html_text()

finaldata <- data.frame(matrix(mydata, ncol=7, byrow=TRUE))

names(finaldata) <- col_name

finaldata

                     Incident                                  Location    

    Reported                              Occurred
1                           Theft       1115 E. 58th St. (Walker Bike Rack) 6/1/15 12:18 PM 5/31/15 to 6/1/15 8:00 PM to 12:00 PM
2                     Information                          5835 S. Kimbark   6/1/15 3:57 PM                        6/1/15 3:55 PM
3                     Information                  1025 E. 58th St. (Swift)  6/2/15 2:18 AM                        6/2/15 2:18 AM
4 Non-Criminal Damage to Property                850 E. 63rd St. (Car Wash)  6/2/15 8:48 AM                        6/2/15 8:00 AM
5     Criminal Damage to Property 5631 S. Cottage Grove (Parking Structure)  6/2/15 7:32 PM             6/2/15 6:45 PM to 7:30 PM
                                                                                                                   Comments / Nature of Fire Disposition
1                                                                                       Bicycle secured to bike rack taken by unknown person        Open
2             Unknown person used staff member's personal information to file a fraudulent claim with U.S. Social Security Admin. / CPD case         CPD
3 Three unaffiliated individuals reported tampering with bicycles in bike rack / Subjects were given trespass warnings and sent on their way      Closed
4                                                                      Rear wiper blade assembly damaged on UC owned vehicle during car wash      Closed
5                                                           Unknown person(s) spray painted graffiti on north concrete wall of the structure        Open
  UCPDI#
1 E00344
2 E00345
3 E00346
4 E00347
5 E00348

这篇关于当缺少&lt；tr&gt；标记时，使用rvest R-擦除HTML表格的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！