raster::clump not working?

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raster::clump not working?

João Carreiras
Hi!

I've been trying to run the clump command but the output is consistently a
raster with values == 1. Please find below an example.

I'm sure I'm doing something stupid. However, the command is really
straightforward and I can't seem to identify what the problem might be.

Any help really appreciated.
Thanks
Joao

r <- raster(ncols=36, nrows=18)
x <- init(r, fun='cell')
x
class       : RasterLayer
dimensions  : 18, 36, 648  (nrow, ncol, ncell)
resolution  : 10, 10  (x, y)
extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
data source : in memory
names       : layer
values      : 1, 648  (min, max)
a <- clump(x)
a
class       : RasterLayer
dimensions  : 18, 36, 648  (nrow, ncol, ncell)
resolution  : 10, 10  (x, y)
extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
data source : in memory
names       : clumps
values      : 1, 1  (min, max)

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Re: raster::clump not working?

Ben Tupper
Hi,

I think it is actually correct - there is only one 'clump' of connected cells.  In raster clumps are separated from other clumps by backgound (0 or NA).  In your example there is no background anywhere so there is just one clump.

You can see the difference if you divide x in to halves with a row of NAs.  Note that limited spatial extent so the clumping doesn't wrap around the globe which it will for [-180, 180].

r <- raster(ncols=36, nrows=18, xmn = 0, xmx = 36, ymn = 0, ymx = 18)
x <- init(r, fun='cell')
 
x[9,1:36] <- NA
y <- clump(x)
y
# class       : RasterLayer
# dimensions  : 18, 36, 648  (nrow, ncol, ncell)
# resolution  : 1, 1  (x, y)
# extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
# coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
# data source : in memory
# names       : clumps
# values      : 1, 2  (min, max)

x[1:18, 18] <- NA
y
# class       : RasterLayer
# dimensions  : 18, 36, 648  (nrow, ncol, ncell)
# resolution  : 1, 1  (x, y)
# extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
# coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
# data source : in memory
# names       : clumps
# values      : 1, 4  (min, max)


Cheers,
Ben


> On May 25, 2018, at 6:00 AM, João Carreiras <[hidden email]> wrote:
>
> Hi!
>
> I've been trying to run the clump command but the output is consistently a
> raster with values == 1. Please find below an example.
>
> I'm sure I'm doing something stupid. However, the command is really
> straightforward and I can't seem to identify what the problem might be.
>
> Any help really appreciated.
> Thanks
> Joao
>
> r <- raster(ncols=36, nrows=18)
> x <- init(r, fun='cell')
> x
> class       : RasterLayer
> dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> resolution  : 10, 10  (x, y)
> extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : layer
> values      : 1, 648  (min, max)
> a <- clump(x)
> a
> class       : RasterLayer
> dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> resolution  : 10, 10  (x, y)
> extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : clumps
> values      : 1, 1  (min, max)
>
> _______________________________________________
> R-sig-Geo mailing list
> [hidden email]
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>

Ben Tupper
Bigelow Laboratory for Ocean Sciences
60 Bigelow Drive, P.O. Box 380
East Boothbay, Maine 04544
http://www.bigelow.org

Ecological Forecasting: https://eco.bigelow.org/






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Re: raster::clump not working?

Bede-Fazekas Ákos
In reply to this post by João Carreiras
Dear Joao,
I think function clump() works as it should be. A toy example:
x <- raster(matrix(sample(x = c(NA, NA, NA, 1), size = 36*18, replace =
TRUE), ncol=36, nrow=18))
plot(x)
plot(clump(x))

Maybe you are searching for a function that aggregate those cells that
have the same value?
In this case it would do what you want (I'm sure there is a more
straightforward way...):
r <- raster(ncols=36, nrows=18)
x <- init(r, fun='cell')
y <- layerize(x)
ids <- calc(x = y, fun = function(layers)
{return(which(as.logical(layers))[1])})
plot(ids)

HTH,
Ákos Bede-Fazekas
Hungarian Academy of Sciences


2018.05.25. 12:00 keltezéssel, João Carreiras írta:

> Hi!
>
> I've been trying to run the clump command but the output is consistently a
> raster with values == 1. Please find below an example.
>
> I'm sure I'm doing something stupid. However, the command is really
> straightforward and I can't seem to identify what the problem might be.
>
> Any help really appreciated.
> Thanks
> Joao
>
> r <- raster(ncols=36, nrows=18)
> x <- init(r, fun='cell')
> x
> class       : RasterLayer
> dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> resolution  : 10, 10  (x, y)
> extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : layer
> values      : 1, 648  (min, max)
> a <- clump(x)
> a
> class       : RasterLayer
> dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> resolution  : 10, 10  (x, y)
> extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : clumps
> values      : 1, 1  (min, max)
>
> _______________________________________________
> R-sig-Geo mailing list
> [hidden email]
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>

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Re: raster::clump not working?

João Carreiras
In reply to this post by Ben Tupper
Dear Ben,

Thank you for your prompt reply.

Now I see what clump does. I just thought clump would give the same
result as ArcGIS "Region Group". I need some command to assign a
different value to each patch. And by patch I mean contiguous pixels
having the same value, so that in this (absurd) example I would get
648 patches.

Take care
Joao

On 25 May 2018 at 11:35, Ben Tupper <[hidden email]> wrote:

> Hi,
>
> I think it is actually correct - there is only one 'clump' of connected
> cells.  In raster clumps are separated from other clumps by backgound (0 or
> NA).  In your example there is no background anywhere so there is just one
> clump.
>
> You can see the difference if you divide x in to halves with a row of NAs.
> Note that limited spatial extent so the clumping doesn't wrap around the
> globe which it will for [-180, 180].
>
> r <- raster(ncols=36, nrows=18, xmn = 0, xmx = 36, ymn = 0, ymx = 18)
> x <- init(r, fun='cell')
>
> x[9,1:36] <- NA
> y <- clump(x)
> y
> # class       : RasterLayer
> # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> # resolution  : 1, 1  (x, y)
> # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
> # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> # data source : in memory
> # names       : clumps
> # values      : 1, 2  (min, max)
>
> x[1:18, 18] <- NA
> y
> # class       : RasterLayer
> # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> # resolution  : 1, 1  (x, y)
> # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
> # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> # data source : in memory
> # names       : clumps
> # values      : 1, 4  (min, max)
>
>
> Cheers,
> Ben
>
>
> On May 25, 2018, at 6:00 AM, João Carreiras <[hidden email]> wrote:
>
> Hi!
>
> I've been trying to run the clump command but the output is consistently a
> raster with values == 1. Please find below an example.
>
> I'm sure I'm doing something stupid. However, the command is really
> straightforward and I can't seem to identify what the problem might be.
>
> Any help really appreciated.
> Thanks
> Joao
>
> r <- raster(ncols=36, nrows=18)
> x <- init(r, fun='cell')
> x
> class       : RasterLayer
> dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> resolution  : 10, 10  (x, y)
> extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : layer
> values      : 1, 648  (min, max)
> a <- clump(x)
> a
> class       : RasterLayer
> dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> resolution  : 10, 10  (x, y)
> extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> data source : in memory
> names       : clumps
> values      : 1, 1  (min, max)
>
> _______________________________________________
> R-sig-Geo mailing list
> [hidden email]
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>
>
> Ben Tupper
> Bigelow Laboratory for Ocean Sciences
> 60 Bigelow Drive, P.O. Box 380
> East Boothbay, Maine 04544
> http://www.bigelow.org
>
> Ecological Forecasting: https://eco.bigelow.org/
>
>
>
>
>

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Re: raster::clump not working?

Michael Sumner-2
Joao, this is what you are after I think.  It's important to use
sf/fasterize otherwise any holes filled by other patches won't be
identified (and it's faster). It won't scale well given rasterToPolygons,
but there might be other options using sf related tricks.

library(raster)
r <- raster(volcano) %/% 20
## p has six distinct values (multipolygons)
p <- rasterToPolygons(r, dissolve = TRUE)
## pp has ten distinct patches
pp <- disaggregate(p)
pp$patch <- seq_len(nrow(pp))

## back to raster
#rr <- rasterize(pp, r, field = pp$patch)
# or faster with sf/fasterize (also this gets the holes filled correctly)
rr <- fasterize::fasterize(sf::st_as_sf(pp), r, field = "patch")
unique(values(rr))

Cheers, Mike.


On Fri, 25 May 2018 at 21:15 João Carreiras <[hidden email]> wrote:

> Dear Ben,
>
> Thank you for your prompt reply.
>
> Now I see what clump does. I just thought clump would give the same
> result as ArcGIS "Region Group". I need some command to assign a
> different value to each patch. And by patch I mean contiguous pixels
> having the same value, so that in this (absurd) example I would get
> 648 patches.
>
> Take care
> Joao
>
> On 25 May 2018 at 11:35, Ben Tupper <[hidden email]> wrote:
> > Hi,
> >
> > I think it is actually correct - there is only one 'clump' of connected
> > cells.  In raster clumps are separated from other clumps by backgound (0
> or
> > NA).  In your example there is no background anywhere so there is just
> one
> > clump.
> >
> > You can see the difference if you divide x in to halves with a row of
> NAs.
> > Note that limited spatial extent so the clumping doesn't wrap around the
> > globe which it will for [-180, 180].
> >
> > r <- raster(ncols=36, nrows=18, xmn = 0, xmx = 36, ymn = 0, ymx = 18)
> > x <- init(r, fun='cell')
> >
> > x[9,1:36] <- NA
> > y <- clump(x)
> > y
> > # class       : RasterLayer
> > # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > # resolution  : 1, 1  (x, y)
> > # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
> > # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > # data source : in memory
> > # names       : clumps
> > # values      : 1, 2  (min, max)
> >
> > x[1:18, 18] <- NA
> > y
> > # class       : RasterLayer
> > # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > # resolution  : 1, 1  (x, y)
> > # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
> > # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > # data source : in memory
> > # names       : clumps
> > # values      : 1, 4  (min, max)
> >
> >
> > Cheers,
> > Ben
> >
> >
> > On May 25, 2018, at 6:00 AM, João Carreiras <[hidden email]>
> wrote:
> >
> > Hi!
> >
> > I've been trying to run the clump command but the output is consistently
> a
> > raster with values == 1. Please find below an example.
> >
> > I'm sure I'm doing something stupid. However, the command is really
> > straightforward and I can't seem to identify what the problem might be.
> >
> > Any help really appreciated.
> > Thanks
> > Joao
> >
> > r <- raster(ncols=36, nrows=18)
> > x <- init(r, fun='cell')
> > x
> > class       : RasterLayer
> > dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > resolution  : 10, 10  (x, y)
> > extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> > coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > data source : in memory
> > names       : layer
> > values      : 1, 648  (min, max)
> > a <- clump(x)
> > a
> > class       : RasterLayer
> > dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > resolution  : 10, 10  (x, y)
> > extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> > coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > data source : in memory
> > names       : clumps
> > values      : 1, 1  (min, max)
> >
> > _______________________________________________
> > R-sig-Geo mailing list
> > [hidden email]
> > https://stat.ethz.ch/mailman/listinfo/r-sig-geo
> >
> >
> > Ben Tupper
> > Bigelow Laboratory for Ocean Sciences
> > 60 Bigelow Drive, P.O. Box 380
> > East Boothbay, Maine 04544
> > http://www.bigelow.org
> >
> > Ecological Forecasting: https://eco.bigelow.org/
> >
> >
> >
> >
> >
>
> _______________________________________________
> R-sig-Geo mailing list
> [hidden email]
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>
--
Dr. Michael Sumner
Software and Database Engineer
Australian Antarctic Division
203 Channel Highway
Kingston Tasmania 7050 Australia

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Re: raster::clump not working?

Michael Treglia
In reply to this post by João Carreiras
Check out SDMTools::ConnCompLabel
I think that will get you what you're after.

Hope that helps!
Mike


Please pardon any typos, this message was sent from a mobile device.

On Fri, May 25, 2018, 7:15 AM João Carreiras <[hidden email]> wrote:

> Dear Ben,
>
> Thank you for your prompt reply.
>
> Now I see what clump does. I just thought clump would give the same
> result as ArcGIS "Region Group". I need some command to assign a
> different value to each patch. And by patch I mean contiguous pixels
> having the same value, so that in this (absurd) example I would get
> 648 patches.
>
> Take care
> Joao
>
> On 25 May 2018 at 11:35, Ben Tupper <[hidden email]> wrote:
> > Hi,
> >
> > I think it is actually correct - there is only one 'clump' of connected
> > cells.  In raster clumps are separated from other clumps by backgound (0
> or
> > NA).  In your example there is no background anywhere so there is just
> one
> > clump.
> >
> > You can see the difference if you divide x in to halves with a row of
> NAs.
> > Note that limited spatial extent so the clumping doesn't wrap around the
> > globe which it will for [-180, 180].
> >
> > r <- raster(ncols=36, nrows=18, xmn = 0, xmx = 36, ymn = 0, ymx = 18)
> > x <- init(r, fun='cell')
> >
> > x[9,1:36] <- NA
> > y <- clump(x)
> > y
> > # class       : RasterLayer
> > # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > # resolution  : 1, 1  (x, y)
> > # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
> > # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > # data source : in memory
> > # names       : clumps
> > # values      : 1, 2  (min, max)
> >
> > x[1:18, 18] <- NA
> > y
> > # class       : RasterLayer
> > # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > # resolution  : 1, 1  (x, y)
> > # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
> > # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > # data source : in memory
> > # names       : clumps
> > # values      : 1, 4  (min, max)
> >
> >
> > Cheers,
> > Ben
> >
> >
> > On May 25, 2018, at 6:00 AM, João Carreiras <[hidden email]>
> wrote:
> >
> > Hi!
> >
> > I've been trying to run the clump command but the output is consistently
> a
> > raster with values == 1. Please find below an example.
> >
> > I'm sure I'm doing something stupid. However, the command is really
> > straightforward and I can't seem to identify what the problem might be.
> >
> > Any help really appreciated.
> > Thanks
> > Joao
> >
> > r <- raster(ncols=36, nrows=18)
> > x <- init(r, fun='cell')
> > x
> > class       : RasterLayer
> > dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > resolution  : 10, 10  (x, y)
> > extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> > coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > data source : in memory
> > names       : layer
> > values      : 1, 648  (min, max)
> > a <- clump(x)
> > a
> > class       : RasterLayer
> > dimensions  : 18, 36, 648  (nrow, ncol, ncell)
> > resolution  : 10, 10  (x, y)
> > extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
> > coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
> > data source : in memory
> > names       : clumps
> > values      : 1, 1  (min, max)
> >
> > _______________________________________________
> > R-sig-Geo mailing list
> > [hidden email]
> > https://stat.ethz.ch/mailman/listinfo/r-sig-geo
> >
> >
> > Ben Tupper
> > Bigelow Laboratory for Ocean Sciences
> > 60 Bigelow Drive, P.O. Box 380
> > East Boothbay, Maine 04544
> > http://www.bigelow.org
> >
> > Ecological Forecasting: https://eco.bigelow.org/
> >
> >
> >
> >
> >
>
> _______________________________________________
> R-sig-Geo mailing list
> [hidden email]
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>

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Re: raster::clump not working?

João Carreiras
In reply to this post by Michael Sumner-2
Dear Mike,

great and many thanks as this is exactly what I was after.

Cheers
Joao

On 25 May 2018 at 12:58, Michael Sumner <[hidden email]> wrote:

> Joao, this is what you are after I think.  It's important to use
> sf/fasterize otherwise any holes filled by other patches won't be identified
> (and it's faster). It won't scale well given rasterToPolygons, but there
> might be other options using sf related tricks.
>
> library(raster)
> r <- raster(volcano) %/% 20
> ## p has six distinct values (multipolygons)
> p <- rasterToPolygons(r, dissolve = TRUE)
> ## pp has ten distinct patches
> pp <- disaggregate(p)
> pp$patch <- seq_len(nrow(pp))
>
> ## back to raster
> #rr <- rasterize(pp, r, field = pp$patch)
> # or faster with sf/fasterize (also this gets the holes filled correctly)
> rr <- fasterize::fasterize(sf::st_as_sf(pp), r, field = "patch")
> unique(values(rr))
>
> Cheers, Mike.
>
>
> On Fri, 25 May 2018 at 21:15 João Carreiras <[hidden email]> wrote:
>>
>> Dear Ben,
>>
>> Thank you for your prompt reply.
>>
>> Now I see what clump does. I just thought clump would give the same
>> result as ArcGIS "Region Group". I need some command to assign a
>> different value to each patch. And by patch I mean contiguous pixels
>> having the same value, so that in this (absurd) example I would get
>> 648 patches.
>>
>> Take care
>> Joao
>>
>> On 25 May 2018 at 11:35, Ben Tupper <[hidden email]> wrote:
>> > Hi,
>> >
>> > I think it is actually correct - there is only one 'clump' of connected
>> > cells.  In raster clumps are separated from other clumps by backgound (0
>> > or
>> > NA).  In your example there is no background anywhere so there is just
>> > one
>> > clump.
>> >
>> > You can see the difference if you divide x in to halves with a row of
>> > NAs.
>> > Note that limited spatial extent so the clumping doesn't wrap around the
>> > globe which it will for [-180, 180].
>> >
>> > r <- raster(ncols=36, nrows=18, xmn = 0, xmx = 36, ymn = 0, ymx = 18)
>> > x <- init(r, fun='cell')
>> >
>> > x[9,1:36] <- NA
>> > y <- clump(x)
>> > y
>> > # class       : RasterLayer
>> > # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
>> > # resolution  : 1, 1  (x, y)
>> > # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
>> > # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
>> > # data source : in memory
>> > # names       : clumps
>> > # values      : 1, 2  (min, max)
>> >
>> > x[1:18, 18] <- NA
>> > y
>> > # class       : RasterLayer
>> > # dimensions  : 18, 36, 648  (nrow, ncol, ncell)
>> > # resolution  : 1, 1  (x, y)
>> > # extent      : 0, 36, 0, 18  (xmin, xmax, ymin, ymax)
>> > # coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
>> > # data source : in memory
>> > # names       : clumps
>> > # values      : 1, 4  (min, max)
>> >
>> >
>> > Cheers,
>> > Ben
>> >
>> >
>> > On May 25, 2018, at 6:00 AM, João Carreiras <[hidden email]>
>> > wrote:
>> >
>> > Hi!
>> >
>> > I've been trying to run the clump command but the output is consistently
>> > a
>> > raster with values == 1. Please find below an example.
>> >
>> > I'm sure I'm doing something stupid. However, the command is really
>> > straightforward and I can't seem to identify what the problem might be.
>> >
>> > Any help really appreciated.
>> > Thanks
>> > Joao
>> >
>> > r <- raster(ncols=36, nrows=18)
>> > x <- init(r, fun='cell')
>> > x
>> > class       : RasterLayer
>> > dimensions  : 18, 36, 648  (nrow, ncol, ncell)
>> > resolution  : 10, 10  (x, y)
>> > extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
>> > coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
>> > data source : in memory
>> > names       : layer
>> > values      : 1, 648  (min, max)
>> > a <- clump(x)
>> > a
>> > class       : RasterLayer
>> > dimensions  : 18, 36, 648  (nrow, ncol, ncell)
>> > resolution  : 10, 10  (x, y)
>> > extent      : -180, 180, -90, 90  (xmin, xmax, ymin, ymax)
>> > coord. ref. : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
>> > data source : in memory
>> > names       : clumps
>> > values      : 1, 1  (min, max)
>> >
>> > _______________________________________________
>> > R-sig-Geo mailing list
>> > [hidden email]
>> > https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>> >
>> >
>> > Ben Tupper
>> > Bigelow Laboratory for Ocean Sciences
>> > 60 Bigelow Drive, P.O. Box 380
>> > East Boothbay, Maine 04544
>> > http://www.bigelow.org
>> >
>> > Ecological Forecasting: https://eco.bigelow.org/
>> >
>> >
>> >
>> >
>> >
>>
>> _______________________________________________
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>
> --
> Dr. Michael Sumner
> Software and Database Engineer
> Australian Antarctic Division
> 203 Channel Highway
> Kingston Tasmania 7050 Australia
>

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