我在R中创建了一系列命令，这些命令可以使用特定的URL完成工作。我想遍历驻留在单独文本文件中的URL列表上的一系列命令。如何一次将列表调用到命令中？
我不知道此编程操作的正确术语是什么。我研究了脚本和批处理编程，但这不是我想要做的。
# URL that comes from list
URL <- "http://www.urlfromlist.com"
# Load URL
theurl <- getURL(URL,.opts = list(ssl.verifypeer = FALSE) )
# Read the tables
tables <- readHTMLTable(theurl)
# Create a list
tables <- list.clean(tables, fun = is.null, recursive = FALSE)
# Convert the list to a data frame
df <- do.call(rbind.data.frame, tables)
# Save dataframe out as a csv file
write.csv(df2, file = dynamicname, row.names=FALSE)
上面的代码是我在做什么。每次列表中的第一个变量都必须是一个不同的URL-冲洗并重复。谢谢！
更新的代码-这仍然不会写出任何文件，但是可以运行。
# Function to pull tables from list of URLs
URLfunction<- function(x){
# URL that comes from list
URL <- x
# Load URL
theurl <- RCurl::getURL(URL,.opts = list(ssl.verifypeer = FALSE) )
# Read the tables
tables <- XML::readHTMLTable(theurl)
# Create a list
tables <- rlist::list.clean(tables, fun = is.null, recursive = FALSE)
# Convert the list to a data frame
df <- do.call(rbind,tables)
# Split date and time column out
df2 <- separate(df, "Date / Time", c("Date", "Time"), sep = " ")
# Fill the missing column with text, in this case shapename
shapename <- qdapRegex::ex_between(URL, "ndxs", ".html")
df2$Shape <- shapename
# Save dataframe out as a csv file
write.csv(result, paste0(shapename, '.csv', row.names=FALSE))
return(df2)
}
URL <- read.csv("PATH", header = FALSE)
purrr::map_df(URL, URLfunction) ## Also tried purrr::map_df(URL[,1], URLfunction)
答案 0 :(得分：0)
如果我正确理解您的问题， 我的答案可能与您的问题有关。
library(RCurl)
library(XML)
library(rlist)
library(purrr)
URLfunction<- function(x){
# URL that comes from list
URL <- x
# Load URL
theurl <- RCurl::getURL(URL,.opts = list(ssl.verifypeer = FALSE) )
# Read the tables
tables <- XML::readHTMLTable(theurl)
# Create a list
tables <- rlist::list.clean(tables, fun = is.null, recursive = FALSE)
# Convert the list to a data frame
df <- do.call(rbind,tables)
# Save dataframe out as a csv file
return(df)
}
（我不确定您看起来像什么数据）
URL <- c("https://stackoverflow.com/questions/56139810/how-to-call-a-script-in-another-script-in-r",
"https://stackoverflow.com/questions/56122052/labelling-points-on-a-highcharter-scatter-chart/56123057?noredirect=1#comment98909916_56123057")
result<- purrr::map(URL, URLfunction)
result <- do.call(rbind, result)
如果要通过每个URL写入write.csv，请plz移至URLfunction
write.csv(result, file = dynamicname, row.names=FALSE)
URL <- list("https://stackoverflow.com/questions/56139810/how-to-call-a-script-in-another-script-in-r",
"https://stackoverflow.com/questions/56122052/labelling-points-on-a-highcharter-scatter-chart/56123057?noredirect=1#comment98909916_56123057")
result<- purrr::map_df(URL, URLfunction)
>result
asked today yesterday
1 viewed 35 times <NA>
2 active today <NA>
3 viewed <NA> 34 times
4 active <NA> today
URL <- read.csv("PATH",header = FALSE)
result<- purrr::map_df(URL[,1], URLfunction)
>result
asked today yesterday
1 viewed 35 times <NA>
2 active today <NA>
3 viewed <NA> 34 times
4 active <NA> today
URLfunction<- function(x){
# URL that comes from list
URL <- x
# Load URL
theurl <- RCurl::getURL(URL,.opts = list(ssl.verifypeer = FALSE) )
# Read the tables
tables <- XML::readHTMLTable(theurl)
# Create a list
tables <- rlist::list.clean(tables, fun = is.null, recursive = FALSE)
# Convert the list to a data frame
df <- do.call(rbind,tables)
# Split date and time column out
df2 <- tidyr::separate(df, "Date / Time", c("Date", "Time"), sep = " ")
# Fill the missing column with text, in this case shapename
shapename <- unlist(qdapRegex::ex_between(URL, "ndxs", ".html"))
# qdapRegex::ex_between returns list type, when it added to df2 it couldn't be saved.
# So i added 'unlist'
df2$Shape <- shapename
# Save dataframe out as a csv file
write.csv(df2, paste0(shapename, '.csv'), row.names=FALSE)
# Here are two error.
# First, You maked the data named 'df2' not 'result'. So i changed result -->df2
# Second, row.names is not the 'paste0' attributes, it is 'write.csv's attributes.
return(df2)
}
定义上述功能后，
URL = c("nuforc.org/webreports/ndxsRectangle.html",
"nuforc.org/webreports/ndxsRound.html")
RESULT = purrr::map_df(URL, URLfunction) ## Also tried purrr::map_df(URL[,1], URLfunction)
最后，我得到下面的结果
1. Rectangle.csv, Round.csv files on your desktop(Saved path).
2. Returning row binded data frame looks like below (2011 x 8)
> RESULT[1,]
Date Time City State Shape Duration
1 5/2/19 00:20 Honolulu HI Rectangle 3 seconds
Summary
1 Several of rectangles connected in different LED like colors. Such as red, green, blue, etc. ;above Waikiki. ((anonymous report))
Posted
1 5/9/19