Re: [R-sig-Geo] Converting UTMs to SpatialPolygons object

2012-07-16 Thread Michael Sumner 
Here we go, I'm assuming each ring is its own simple object, and a few
other things.

id = rep(seq(1,3),each=12)
az = rep(seq(0,359,30),3)

## assume you meant to use all ids here?
d = data.frame(id,az)
d$dist = round(rnorm(36,10,3),1)
xp = function(azimuth, r){cos(((90-azimuth)*pi)/180)*r}
yp =  function(azimuth, r){sin(((90-azimuth)*pi)/180)*r}
ctr_e = rnorm(3,667314,50)
ctr_n = rnorm(3,4784480,50)

d$utm_e = round(xp(d$az,d$dist),1) + ctr_e[d$id]
d$utm_n = round(yp(d$az,d$dist),1) + ctr_n[d$id]

library(sp)
myCRS = CRS(+proj=utm +zone=18 +ellps=WGS84)

## create list of coords, including repeat of first row for each
l.coords - lapply(split(d, d$id), function(x)
as.matrix(x[c(seq_len(nrow(x)), 1), c(utm_e, utm_n)]))


l.Polygons - vector(list,length(l.coords))

for (i in seq_len(length(l.coords))) {
l.Polygons[[i]] - Polygons(list(Polygon(l.coords[i])), as.character(i))
}

SpPolys - SpatialPolygons(l.Polygons, proj4string = myCRS)

plot(SpPolys, col = c(grey, red, blue))


On Mon, Jul 16, 2012 at 10:24 AM,  s...@swbigelow.net wrote:


 It seems my data-generating code was cut off. Here's another try:

 id = rep(seq(1,3),each=12)# Generate polygon
 IDs'
 az = rep(seq(0,359,30),3)   # Generate
 azimuth sequence
 c = data.frame(id
 [1],az)# Combine in
 data frame
 c$dist = round(rnorm(36,10,3),1)  # Generate random distances from
 center of polygon

 xp = function(azimuth, r){cos(((90-azimuth)*pi)/180)*r}
   # Function to calculate horizontal distance from polygon
 center

 yp =  function(azimuth, r){sin(((90-azimuth)*pi)/180)*r}
   # Function to calculate vertical distance from polygon
 center

 ctr_e = rnorm(3,667314,50)   # Randomly select eastings
 for polygon centers
 ctr_n = rnorm(3,4784480,50) # Randomly select northings for
 polygon centers

 c$utm_e = round(xp(c$az,c$dist),1) + ctr_e[c$id]  # Calculate
 point eastings
 c$utm_n = round(yp(c$az,c$dist),1) + ctr_n[c$id]  # Calculate point
 northings

 myCRS = CRS(+proj=utm +zone=18 +ellps=WGS84)# define
 proj4string

 Appreciatively,

 Seth Bigelow



 Links:
 --
 [1] http://sitemail.hostway.com/http:/


 [[alternative HTML version deleted]]


 ___
 R-sig-Geo mailing list
 R-sig-Geo@r-project.org
 https://stat.ethz.ch/mailman/listinfo/r-sig-geo




-- 
Michael Sumner
Hobart, Australia
e-mail: mdsum...@gmail.com

___
R-sig-Geo mailing list
R-sig-Geo@r-project.org
https://stat.ethz.ch/mailman/listinfo/r-sig-geo

Re: [R-sig-Geo] Converting UTMs to SpatialPolygons object

2012-07-16 Thread seth 
Michael,  the code for converting a data frame containing UTM
coordinates identified by group, into SpatialPolygon objects, works
spectacularly well. Many thanks --Seth

- Original Message -
 From:Michael Sumner 
To:
Cc:
Sent:Mon, 16 Jul 2012 16:30:46 +1000
Subject:Re: [R-sig-Geo] Converting UTMs to SpatialPolygons object

Here we go, I'm assuming each ring is its own simple object, and a
few
other things.

id = rep(seq(1,3),each=12)
az = rep(seq(0,359,30),3)

## assume you meant to use all ids here?
d = dataframe(id [1],az)
d$dist = round(rnorm(36,10,3),1)
xp = function(azimuth, r){cos(((90-azimuth)*pi)/180)*r}
yp = function(azimuth, r){sin(((90-azimuth)*pi)/180)*r}
ctr_e = rnorm(3,667314,50)
ctr_n = rnorm(3,4784480,50)

d$utm_e = round(xp(d$az,d$dist),1) + ctr_e[d$id]
d$utm_n = round(yp(d$az,d$dist),1) + ctr_n[d$id]

library(sp)
myCRS = CRS(+proj=utm +zone=18 +ellps=WGS84)

## create list of coords, including repeat of first row for each
l.coords [2]  az = rep(seq(0,359,30),3) # Generate
 azimuth sequence
 c = data.frame(id [11]
 [1],az) # Combine in
 data frame
 c$dist = round(rnorm(36,10,3),1) # Generate random distances from
 center of polygon

 xp = function(azimuth, r){cos(((90-azimuth)*pi)/180)*r}
 # Function to calculate horizontal distance from polygon
 center

 yp = function(azimuth, r){sin(((90-azimuth)*pi)/180)*r}
 # Function to calculate vertical distance from polygon
 center

 ctr_e = rnorm(3,667314,50) # Randomly select eastings
 for polygon centers
 ctr_n = rnorm(3,4784480,50) # Randomly select northings for
 polygon centers

 c$utm_e = round(xp(c$az,c$dist),1) + ctr_e[c$id] # Calculate
 point eastings
 c$utm_n = round(yp(c$az,c$dist),1) + ctr_n[c$id] # Calculate point
 northings

 myCRS = CRS(+proj=utm +zone=18 +ellps=WGS84) # define
 proj4string

 Appreciatively,

 Seth Bigelow



 Links:
 --
 [1] http://sitemail.hostway.com/http:/ [12]


 [[alternative HTML version deleted]]


 ___
 R-sig-Geo mailing list
 R-sig-Geo@r-project.org [13]
 https://stat.ethz.ch/mailman/listinfo/r-sig-geo [14]


-- 
Michael Sumner
Hobart, Australia
e-mail: mdsum...@gmail.com [15]


Links:
--
[1] http://sitemail.hostway.com/http:/
[2] http://l.coords/
[3] http://sitemail.hostway.com/http:/
[4] http://l.polygons/
[5] http://sitemail.hostway.com/http:/
[6] http://sitemail.hostway.com/http:/
[7] http://sitemail.hostway.com/http:/
[8] http://sitemail.hostway.com/http:/
[9] http://sitemail.hostway.com/http:/
[10] http://l.polygons/
[11] http://sitemail.hostway.com/http:/
[12] http://sitemail.hostway.com/http:/
[13] mailto:R-sig-Geo@r-project.org
[14] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[15] mailto:mdsum...@gmail.com


[[alternative HTML version deleted]]

___
R-sig-Geo mailing list
R-sig-Geo@r-project.org
https://stat.ethz.ch/mailman/listinfo/r-sig-geo

Re: [R-sig-Geo] Converting UTMs to SpatialPolygons object

2012-07-15 Thread Michael Sumner 
If you sent code it did not survive the journey. See the vignette in
sp for how to build polygons from scratch, section 7.1.

library(sp)
vignette(intro_sp)



On Mon, Jul 16, 2012 at 10:12 AM,  s...@swbigelow.net wrote:


 r-sig-geo listers:

 Can anyone provide code or suggest commands for converting a data
 frame with UTMS to a SpatialPolygons (sp package) object? Below, I
 provide code to generate a sample dataframe, with three ordered
 sequences of twelve coordinate pairs each.

 id

 [[alternative HTML version deleted]]

 ___
 R-sig-Geo mailing list
 R-sig-Geo@r-project.org
 https://stat.ethz.ch/mailman/listinfo/r-sig-geo



-- 
Michael Sumner
Hobart, Australia
e-mail: mdsum...@gmail.com

___
R-sig-Geo mailing list
R-sig-Geo@r-project.org
https://stat.ethz.ch/mailman/listinfo/r-sig-geo