Re: [R] Removing polygons from shapefile of Scotland and Islands
I believe mapshaper has functionality for removing small 'islands'. There is a webinterface for mapshaper, but I see there is also an R-package (see https://search.r-project.org/CRAN/refmans/rmapshaper/html/ms_filter_islands.html for island removal). If you want to manually select which islands to keep and which to remove, you can split multipolygons into single polygons. I believe that is possible using st_cast. But if it is just getting the relevant portion of the map on screen. With the plot-command and using st_viewport it is possible to set the part of the map that is drawn. HTH, Jsn On 14-05-2024 15:16, Nick Wray wrote: Hello I have a shapefile of Scotland, including the islands. The river flow data I am using is only for the mainland and for a clearer and larger map I would like to not plot Orkney and Shetland to the north of the mainland, as I don't need them. The map I have I got from https://borders.ukdataservice.ac.uk/easy_download_data.html?data=infuse_ctry_2011 then I put the uk shapefile onto my laptop with no problems (I have sf running) the_uk<-st_read(dsn="C:/Users/nickm/Desktop/Shapefiles/infuse_ctry_2011.shp") scotland<-the_uk[2,] plot(scotland$geometry) This gives me a nice map of Scotland plus islands but obviously there are lots of separate polygons and if I go into the points with something like scot_pts<-unlist(as.data.frame(scotland$geometry)) it's not at all clear how I can get rid of the points I don't want as they don't seem to be listed in any easy way to find where one polygon stops and another starts I am wondering whether this approach is right anyway or whether there is some sf function which would allow me to identify the polygons I want - essentially the big one which is the mainland without lots of elaborate conversions and manipulations Any pointers, thoughts etc much appreciated Thanks Nick Wray [[alternative HTML version deleted]] __ R-help@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. __ R-help@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.
Re: [R] Altrep and translations (was " Description of error is untranslated when ....")
Hello
On the other hand, i find that R_compact_intrange checks whether (r = n2 -
n1 + 1) >= R_XLEN_T_MAX, while seq_colon checks for (r = fabs(n2 - n1)) >=
R_XLEN_T_MAX. And only then n is defined as r + 1 + epsilon. r is not used
again
That is why seq_colon does not reject that size at first and then altrep
does.
Should not line 101 be " if (r + 1 + FLT_EPSILON >= R_XLEN_T_MAX) "
instead of r >= R_XLEN_T_MAX?
El mar, 14 may 2024 a las 4:45, Martin Maechler ()
escribió:
> > Ivan Krylov via R-help
> > on Tue, 14 May 2024 08:08:58 +0300 writes:
>
> > Dear Ricardo Villalba, Thank you for spotting this corner
> > case!
>
> > В Mon, 13 May 2024 11:37:57 -0300 Ricardo Villalba
> > пишет:
>
> >> I track the messages to be coded here:
> >>
> https://github.com/r-devel/r-svn/blob/abe625945c4402cd2bb97b5a64e7469db3e904f0/src/main/altclasses.c#L580
> >> and here
> >>
> https://github.com/r-devel/r-svn/blob/abe625945c4402cd2bb97b5a64e7469db3e904f0/src/main/seq.c#L102
>
> > You may have noticed that one of these places lacks the
> > underscore that R uses as the translation keyword: it's
> > _(string) that looks up the translation of the string.
>
> > Would you like to suggest a patch on r-de...@r-project.org
> > or https://bugs.r-project.org ?
>
> > --
> > Best regards, Ivan
>
> Thank you, but, well... for such small changes -- that would be
> quite a bit of (human, i.e. R-core) overhead, but of course is
> generally a good possibility (but here, wait! .. and read on : )
>
> Actually -- this now gets more "R-devel" - appropriate --
> I notice that there are quite a few error("..." .. )
> and also warning("..." ..) calls in
> src/main/altclasses.c *and* in
> src/main/altrep.cand *none* of them asks for translation;
>
> While this could be for historical reasons (code originally much
> by Gabe Becker from outside R-core *and* at first just in a
> separate branch before being merged in to the main (r-devel)
> branch.
> OTOH: There may be good reasons for translations lookup being
> brittle in case of altrep error messages .. and hence left off
> purposely?
>
> Martin
>
> --
> Martin Maechler
> ETH Zurich and R Core Team
>
>
--
®DV!
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[R] Removing polygons from shapefile of Scotland and Islands
Hello I have a shapefile of Scotland, including the islands. The river flow data I am using is only for the mainland and for a clearer and larger map I would like to not plot Orkney and Shetland to the north of the mainland, as I don't need them. The map I have I got from https://borders.ukdataservice.ac.uk/easy_download_data.html?data=infuse_ctry_2011 then I put the uk shapefile onto my laptop with no problems (I have sf running) the_uk<-st_read(dsn="C:/Users/nickm/Desktop/Shapefiles/infuse_ctry_2011.shp") scotland<-the_uk[2,] plot(scotland$geometry) This gives me a nice map of Scotland plus islands but obviously there are lots of separate polygons and if I go into the points with something like scot_pts<-unlist(as.data.frame(scotland$geometry)) it's not at all clear how I can get rid of the points I don't want as they don't seem to be listed in any easy way to find where one polygon stops and another starts I am wondering whether this approach is right anyway or whether there is some sf function which would allow me to identify the polygons I want - essentially the big one which is the mainland without lots of elaborate conversions and manipulations Any pointers, thoughts etc much appreciated Thanks Nick Wray [[alternative HTML version deleted]] __ R-help@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.
[R] Altrep and translations (was " Description of error is untranslated when ....")
> Ivan Krylov via R-help
> on Tue, 14 May 2024 08:08:58 +0300 writes:
> Dear Ricardo Villalba, Thank you for spotting this corner
> case!
> В Mon, 13 May 2024 11:37:57 -0300 Ricardo Villalba
> пишет:
>> I track the messages to be coded here:
>>
https://github.com/r-devel/r-svn/blob/abe625945c4402cd2bb97b5a64e7469db3e904f0/src/main/altclasses.c#L580
>> and here
>>
https://github.com/r-devel/r-svn/blob/abe625945c4402cd2bb97b5a64e7469db3e904f0/src/main/seq.c#L102
> You may have noticed that one of these places lacks the
> underscore that R uses as the translation keyword: it's
> _(string) that looks up the translation of the string.
> Would you like to suggest a patch on r-de...@r-project.org
> or https://bugs.r-project.org ?
> --
> Best regards, Ivan
Thank you, but, well... for such small changes -- that would be
quite a bit of (human, i.e. R-core) overhead, but of course is
generally a good possibility (but here, wait! .. and read on : )
Actually -- this now gets more "R-devel" - appropriate --
I notice that there are quite a few error("..." .. )
and also warning("..." ..) calls in
src/main/altclasses.c *and* in
src/main/altrep.cand *none* of them asks for translation;
While this could be for historical reasons (code originally much
by Gabe Becker from outside R-core *and* at first just in a
separate branch before being merged in to the main (r-devel)
branch.
OTOH: There may be good reasons for translations lookup being
brittle in case of altrep error messages .. and hence left off
purposely?
Martin
--
Martin Maechler
ETH Zurich and R Core Team
__
R-help@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.
