[R] suggestion of regex pattern

Fernando Gama f.fabiogama88 at gmail.com
Sun Apr 19 02:44:50 CEST 2015


Ok, I'll try to do this...

Thanks :D

2015-04-18 18:55 GMT-03:00 Boris Steipe <boris.steipe at utoronto.ca>:

> Re-reading your question and taking a wild guess, perhaps you are looking
> for parse() and eval() ...
>
> xyz <- data.frame( a=c(1,2), b=c(3,4))
> xyz
>
>   a b
> 1 1 3
> 2 2 4
>
> expp <- parse(text="xyz$a > 1 & xyz$b == 4")   # turn a string into an
> expression
> expp
>
> expression(xyz$a > 1 & xyz$b == 4)
>
> xyz[eval(expp), ]                              # evaluate an expression in
> place
>   a b
> 2 2 4
>
> ... but really, it's just a guess at what you might be trying to do.
>
> B.
>
>
>
>
> On Apr 18, 2015, at 1:30 PM, Boris Steipe <boris.steipe at utoronto.ca>
> wrote:
>
> > Sorry - it's not entirely clear to me what you need to do.
> >
> > See here for some hints on how to ask questions on this list. I'm sure
> we'll be able to help quickly.
> > http://adv-r.had.co.nz/Reproducibility.html
> >
> http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example
> > (and don't post in HTML   :-)
> >
> >
> > B.
> >
> > On Apr 18, 2015, at 11:10 AM, Fernando Gama <f.fabiogama88 at gmail.com>
> wrote:
> >
> >> Hello Boris,
> >>
> >> thanks for your response.
> >>
> >> So, firstly considered that  i've been input a set of serches strings
> (.txt format) and i'm using regex to transform in a suitable  format to my
> script. This part is a final part of my code and i wish putting in input to
> a subset.
> >>
> >> (.txt formatted)
> >>
> >> ---- STRINGS (INPUT)
> >>
> >> [1]  "municipio =='Limeira' "
> >> [2]  "municipio =='Limeira' & mesincident =='marco' "
> >> [3]  "​municipio =='Limeira' & mesincident =='marco' & trechoklmetros >
> 1.00 12.300"
> >> ...
> >> ..
> >> ..
> >> ..
> >> [n] "......"
> >>
> >> --------------
> >>
> >> desired_fomart <- ​it will reveice all strings to filter in a dataset
> by subset below:
> >>
> >>
> >> a loop each line:
> >>
> >> subset(dataset_read, desired_fomart[i])
> >>
> >> My question: taking into consideration this cenario, in your oppinion
> your reply is my suitable for my problem, whereas i will to map each value
> in database?
> >>
> >> Once again, thank so much! :)
> >>
> >> 2015-04-18 11:04 GMT-03:00 Boris Steipe <boris.steipe at utoronto.ca>:
> >> This is not a regular expression but simply a conjunction (sequence of
> '&') of logical expressions. Moreover it's not wrong. Consider:
> >>
> >> xyz <- data.frame(municipio = c('Limeira'), mesincident = c('marco'),
> trechoklmetros = c(3.00, -4.00, 30))
> >> xyz
> >>
> >>  municipio mesincident trechoklmetros
> >> 1   Limeira       marco              3
> >> 2   Limeira       marco             -4
> >> 3   Limeira       marco             30
> >>
> >>
> >> xyz$municipio =='Limeira' & xyz$mesincident =='marco' &
> xyz$trechoklmetros > 1.00
> >> [1]  TRUE FALSE  TRUE
> >>
> >> xyz$municipio =='Limeira' & xyz$mesincident =='marco' &
> xyz$trechoklmetros > 1.00 & xyz$trechoklmetros <= 12.3
> >> [1]  TRUE FALSE FALSE
> >>
> >>
> >> If there's a problem it seems to be elsewhere.
> >> Cheers,
> >> Boris
> >>
> >>
> >> On Apr 17, 2015, at 4:22 PM, Fernando Gama <f.fabiogama88 at gmail.com>
> wrote:
> >>
> >>> Hello,
> >>>
> >>> I have benn problems to construct the pattern for this:
> >>>
> >>> municipio =='Limeira' & mesincident =='marco' & trechoklmetros > 1.00
> 12.300
> >>>
> >>> I would like:
> >>>
> >>> municipio =='Limeira' & mesincident =='marco' & trechoklmetros > 1.00
> >>> *& **trechoklmetros
> >>> <= *12.300
> >>> ​
> >>> ​Any suggestion?​
> >>>
> >>>
> >>> --
> >>> Att,
> >>>
> >>> Fernando Gama da Mata
> >>>
> >>>      [[alternative HTML version deleted]]
> >>>
> >>> ______________________________________________
> >>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >>> 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.
> >>
> >>
> >>
> >>
> >> --
> >> Att,
> >>
> >> Fernando Gama da Mata
> >>
> >>
> >
> > ______________________________________________
> > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > 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.
>
>


-- 
Att,

Fernando Gama da Mata

Vale of Institute Technology

	[[alternative HTML version deleted]]



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