Problems with the Spatial Reference of a shapefile created with writePolyShape

Hi Manuel

Thank you, I tryed your solution and it works partially

xysp <- SpatialPoints(xy)

proj4string(xysp) <- CRS("+proj=tmerc +lon_0=-84 +lat_0=0 +x_0=500000
+k=0.9999 +datum=WGS84")

xysp

SpatialPoints:
             X       Y
 [1,] 815196.4 1152758
 [2,] 815196.0 1152759
 [3,] 815055.7 1152120
 [4,] 815055.7 1152120
 [5,] 815056.5 1152122
 [6,] 815061.6 1152131.......

Coordinate Reference System (CRS) arguments: +proj=tmerc +lon_0=-84
+lat_0=0 +x_0=500000 +k=0.9999 +datum=WGS84

locoh<- LoCoH.a(xysp, a=657,

unin=c("m"),unout=c("ha"),duplicates=c("random"),amount=NULL)

summary(locoh)

Object of class SpatialPolygonsDataFrame
Coordinates:
       min       max
x  815048.9  815365.8
y 1152113.3 1152759.5
Is projected: TRUE
proj4string :
[+proj=tmerc +lon_0=-84 +lat_0=0 +x_0=500000 +k=0.9999 +datum=WGS84]
Data attributes:
     area            percent
Min.   :  789.5   Min.   : 54.17
1st Qu.:  789.5   1st Qu.: 54.17
Median :  834.9   Median : 60.83
Mean   : 6311.2   Mean   : 69.13
3rd Qu.: 8263.5   3rd Qu.: 85.83
Max.   :31699.1   Max.   :100.00

BUT, when I create the shapefile > writePolyShape(locoh, "Locohraul") the
same problem appear in AarGis 10.0:  "UnKnown Spatial Reference: object
missing spatial reference information, this can be drawn, but can't be
projected."

Then, the object is draw, but not projected. The map of my study area
and the shapefile of my LoCoH.a analysis doesn't match.

Any idea? Thank you



2013/10/30 Manuel Sp?nola <mspinola10 at gmail.com>

Hi David,

You don?t have the CRS.

Try this:

proj4string(xysp) <- CRS("+proj=tmerc +lon_0=-84 +lat_0=0 +x_0=500000
+k=0.9999 +datum=WGS84")

Best,

Manuel Sp?nola


2013/10/30 David Villalobos <avi3187 at gmail.com>

Dear list,

Maybe a silly problem, but I need help to solve it.

At this moment I am working with the R package "adehabitatHR",
specifically with the LoCoH.a (Adaptative LoCoh). I am calculating the
home range of a neotropical bat (Ectophylla alba: Phyllostomidae). My
commands are the followings:

xy<-read.table("clipboard", header=T)

head(xy)

         X       Y

1 815802.7 1151723

2 815816.2 1151717

3 815816.1 1151811

4 816053.5 1151723

5 816027.1 1151698

6 816096.1 1151687

xysp

SpatialPoints:

              X       Y

  [1,] 815802.7 1151723

  [2,] 815816.2 1151717

  [3,] 815816.1 1151811

  [4,] 816053.5 1151723

  [5,] 816027.1 1151698.........

Coordinate Reference System (CRS) arguments: NA


locoh<- LoCoH.a(xysp, a=1419,
unin=c("m"),unout=c("ha"),duplicates=c("random"),amount=NULL)

plot(locoh)

plot(xysp,add=T)

locohhr<- MCHu2hrsize(locoh, percent=seq(10, 100, by=5))

locohhr

            df

10    2935.613

15    2935.613

20    2935.613

25    2935.613........

At this point everything right, and now my purpose is to create a
"shapefile" using the object "locoh" (Class =
SpatialPolygonsDataFrame) with this command:

writePolyShape(locohhr, "LocohI")

Here, the real problem: I want to use the shapefile created on a map
of my study area (in Costa Rica). I have the map in the local
Projected Coordinate System:

 Projected Coordinate System:   Proyeccion_CRTM05

Projection:    Transverse_Mercator

False_Easting: 500000.00000000

False_Northing: 0.00000000

Central_Meridian:      -84.00000000

Scale_Factor:  0.99990000

Latitude_Of_Origin:    0.00000000

Linear Unit:   Meter

Geographic Coordinate System:  GCS_WGS_1984

Datum:  D_WGS_1984

Prime Meridian:        Greenwich

Angular Unit:  Degree


The first step is to read the shapefile in ArcMap 10. When I try to
read the shapefile of my LoCoH.a analysis, I can't do it good because
the following message appear: "UnKnown Spatial Reference: object
missing spatial reference information, this can be drawn, but can't be
projected."

Then, the object is draw, but not projected. The map of my study area
and the shapefile of my LoCoH.a analysis doesn't match.


I want to solve this problem with spatial reference information of my
shapefile(LoCoH.a). I suspect that the way to do it is related with
one part of the command writePolyShape(locoh, "LocohI"), maybe the
part: "proj4string=CRS(as.character(NA)".



Please any help is welcome. I will be very appreciated.


 Since now, THANK YOU.


--

Saludos

David Villalobos Chaves
Maestr?a Acad?mica en Biolog?a
Universidad de Costa Rica

        [[alternative HTML version deleted]]

--
*Manuel Sp?nola, Ph.D.*
Instituto Internacional en Conservaci?n y Manejo de Vida Silvestre
Universidad Nacional
Apartado 1350-3000
Heredia
COSTA RICA
mspinola at una.ac.cr
mspinola10 at gmail.com
Tel?fono: (506) 2277-3598
Fax: (506) 2237-7036
Personal website: Lobito de r?o<https://sites.google.com/site/lobitoderio/>
Institutional website: ICOMVIS <http://www.icomvis.una.ac.cr/>