[R-sig-Geo] Manipulate extract output

[Gustavo Carvalho]

Dear Joseph,

Could you please try this?

names(X) <- 1:length(X)
stack(X)

Gustavo.

On Sun, Apr 24, 2011 at 11:55 AM, jm3389 <jm3389 at columbia.edu> wrote:
> Dear All,
>
> I have been struggling to extract individual pixel values from within a set
> of polygons.
>
> Mbola.shp <- readOGR(dsn="C:/Users/JOX201S/Desktop/Dropbox/LDSF/Mbola",
> "MBSubplot1LULC")
> SMA <- raster("C:/Users/JOX201S/Desktop/Dropbox/LDSF/Mbola/SMA-clipped.img")
>
> X <- extract(SMA, Mbola.shp)
>
> then when I display X I obtain a list:
>
>>X
> [[1]]
>  [1] 0.08505697 0.11521957 0.07027940 0.07027940 0.10559745 0.10363697
> 0.09353689
>  [8] 0.09353689 0.09673717 0.12536806 0.15696177 0.09306118 0.09353689
> 0.09673717
> [15] 0.09306118 0.09306118 0.09669495
>
> [[2]]
>  [1]  0.02609529  0.02609529  0.02996226 -0.00057072  0.02159369  0.02159369
>  [7]  0.04489277  0.02804214  0.02835380  0.06462935  0.06462935  0.02266412
> [13]  0.03684234  0.02083779  0.07917891  0.05502048  0.03577228
>
> [[3]]
>  [1] 0.08705948 0.08705948 0.08622552 0.05902963 0.05902963 0.03294581
> 0.08919024
>  [8] 0.10308155 0.10308155 0.04357137 0.06129387 0.18882106 0.15271443
> 0.15271443
> [15] 0.07749587 0.23532785 0.23532785
>
> [[4]]
>  [1] 0.09554891 0.09314694 0.13511878 0.12017184 0.12056647 0.10497463
> 0.19552167
>  [8] 0.19496135 0.10160323 0.09736327 0.12032449 0.18401594 0.13698930
> 0.09173016
> [15] 0.11627619 0.13992140
>
> [[5]]
>  [1] 0.08130399 0.12848020 0.15129283 0.06018241 0.06018241 0.12764616
> 0.15831620
>  [8] 0.16025396 0.07245398 0.07245398 0.08861573 0.15831620 0.16025396
> 0.07245398
> [15] 0.08861573 0.10879661
>
> [[6]]
>  [1] 0.01403566 0.05509807 0.06573696 0.07086041 0.05806389 0.08060271
> 0.04586258
>  [8] 0.04270630 0.07691538 0.06859619 0.08897498 0.06756449 0.04492125
> 0.04651234
> [15] 0.04652581 0.08224432 0.04266668 0.05377325
>
> [[7]]
>  [1] 0.19860968 0.13489768 0.11530623 0.11530623 0.12832202 0.18902805
> 0.09427368
>  [8] 0.08301217 0.08301217 0.11991798 0.18725793 0.19014162 0.14259814
> 0.14259814
> [15] 0.08376002 0.18725793 0.14259814 0.14259814 0.08376002
>
> [[8]]
>  [1]  0.06091007  0.06091007  0.05323072  0.03962127  0.04709431  0.04709431
>  [7]  0.05578892  0.06078413  0.03223819  0.02318165  0.02318165  0.04193906
> [13]  0.04568461 -0.01365644  0.01866432  0.01866432  0.04833658  0.04675072
> [19]  0.04113418  0.04113418  0.03635887
>
>
> I would like to reshape the list like that:
>
> Pixel value  | Polygon
> 0.08505697     [[1]]
> 0.11521957     [[1]]
> 0.07027940     [[1]]
> 0.07027940     [[1]]
> 0.10559745     [[1]]
> ...
>
> I have tried stack, and the reshape package but haven't been able to
> manipulate the list.
> I am sure it's a very simple function but I've been searching the web for
> days now and nothing really works.
>
> Any suggestion?
> Thanks
> Joseph
>
>
> --
> View this message in context: http://r-sig-geo.2731867.n2.nabble.com/Manipulate-extract-output-tp6301073p6301073.html
> Sent from the R-sig-geo mailing list archive at Nabble.com.
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>