Reputation: 179
I want to use the packages rvest
to pull gas prices from a web page. However, I can not pull the numeric values and have to pull by the html class .sp_p
.
library(rvest)
desmoines <- html("http://www.desmoinesgasprices.com/")
Pull gas prices:
price <- desmoines %>%
html_nodes(".sp_p")
head(price, 3)
Output:
[[1]]
<div class="sp_p">
<div class="p2"></div>
<div class="pd"></div>
<div class="p5"></div>
<div class="p5"></div>
</div>
[[2]]
<div class="sp_p">
<div class="p2"></div>
<div class="pd"></div>
<div class="p5"></div>
<div class="p6"></div>
</div>
[[3]]
<div class="sp_p">
<div class="p2"></div>
<div class="pd"></div>
<div class="p5"></div>
<div class="p7"></div>
</div>
attr(,"class")
[1] "XMLNodeSet"
Now, I want to use the package stringr
to extract the digits from the web scrape, but I can't use stringr
because price
is not an atomic vector. How do I get around this?
Upvotes: 2
Views: 826
Reputation: 23798
Here's one possibility:
library(stringr)
pr <- xml_children(price)
p_raw <- sapply(1:length(pr), function(x) paste(xml_attrs(pr[[x]]),collapse=""))
p_readable <- paste0("$",str_replace_all(p_raw,c("d"=".","p"="")))
#> p_readable
# [1] "$2.49" "$2.57" "$2.59" "$2.59" "$2.59" "$2.59" "$2.59" "$2.59" "$2.61" "$2.64" "$2.67" "$2.68" "$2.68"
#[14] "$2.68" "$3.08" "$2.99" "$2.98" "$2.98" "$2.98" "$2.98" "$2.98" "$2.98" "$2.98" "$2.98" "$2.98" "$2.98"
#[27] "$2.98" "$2.98" "$2.98"
Upvotes: 3