[R] Best way to get the prices from these strings?

[PIKAL Petr]

Hi

Slight modification to get rid of $

as.numeric(gsub(".*\\$(.*)<.*","\\1",thePrices))

Petr


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of dan wang
> Sent: Wednesday, January 29, 2014 3:55 PM
> To: Keith S Weintraub
> Cc: r-help at r-project.org
> Subject: Re: [R] Best way to get the prices from these strings?
>
> I am not sure if below ways are better.
>
> sub(".*>(.*)<.*","\\1",thePrices)
>
> sapply(thePrices, function(x){s=gregexpr(pattern
> ='\\$',x)[[1]][1];e=gregexpr(pattern
> ='<',x)[[1]][1];return(substr(x,s,e-1))})
>
>
> On Wed, Jan 29, 2014 at 9:29 AM, Keith S Weintraub <kw1958 at gmail.com>
> wrote:
>
> > Folks,
> >
> > I got the following prices by scraping a web page just for my own
> > edification:
> >
> > thePrices<-
> > c("id=\"p0\">$69.95</div>", "id=\"p1\">$44.95</div>",
> > "id=\"p2\">$69.95</div>", "id=\"p3\">$59.95</div>",
> > "id=\"p4\">$69.95</div>", "id=\"p5\">$79.95</div>",
> > "id=\"p6\">$89.95</div>", "id=\"p7\">$59.95</div>",
> > "id=\"p8\">$59.95</div>", "id=\"p9\">$79.95</div>",
> > "id=\"p10\">$79.95</div>", "id=\"p11\">$89.95</div>",
> > "id=\"p12\">$89.95</div>", "id=\"p13\">$79.95</div>",
> > "id=\"p14\">$89.95</div>", "id=\"p15\">$79.95</div>",
> > "id=\"p16\">$39.95</div>", "id=\"p17\">$59.95</div>",
> > "id=\"p18\">$69.95</div>", "id=\"p19\">$83.95</div>",
> > "id=\"p20\">$73.95</div>", "id=\"p21\">$83.95</div>",
> > "id=\"p22\">$93.95</div>", "id=\"p23\">$87.95</div>",
> > "id=\"p24\">$91.95</div>", "id=\"p25\">$99.95</div>",
> > "id=\"p26\">$61.95</div>\""
> > )
> >
> > Using lapply and strsplit (twice) unlist etc. I was able to get the
> > result I wanted (the prices as numbers e.g. 59.95)  but I am sure
> that
> > there is a much better way that someone might be able to point out
> for me.
> >
> > Note that I tried various regexes which didn't work.
> >
> > Is part of the difficulty that the strings in thePrices have multiple
> > \"'s in them?
> >
> > Thanks for your time,
> > Best,
> > KW
> >
> > --
> >
> > ______________________________________________
> > R-help at r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
> >
>
>       [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-
> guide.html
> and provide commented, minimal, self-contained, reproducible code.

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