Hi Mike and Erin,
I added the projection to the shape file as suggested by Erin.
Then i plotted the rivers over and plotted my data points (places
where i collected samples). All my data points look accurate.
Thank you so much.
This was my first try working with GIS data. And, it was fun.
Migu
Since you can install rgdal it would be best to go that way (I had
completely missed that you obviously had access to rgdal::spTransform,
please provide the code you are using as asked by the mailing list
guidelines).
library(rgdal)
See ?readOGR
You need a layer name, which can just be the file
Try something like this:
proj4string(nc.river) <- CRS("+proj=lcc +lat_1=36.16
+lat_2=34.34 +lat_0=33.75 +lon_0=-79 +x_0=609601.22 +y_0=0
+ellps=GRS80 +datum=NAD83 +units=m +no_defs")
From: Migun Shakya [microbea...@gmail.com]
Se
Hi Mike,
I tried the rgdal:readOGR, but got an error.
> nc.river<-readOGR("~/hydromaj/hydromaj_arc.shp")
Error in readOGR("~/hydromaj/hydromaj_arc.shp") :
missing layer
Sorry, I am not very familiar with the data structure, but i am
looking at the spatialreference.org. Lets see what i get.
Th
You need an input projection on the data, it doesn't know what you are
transforming FROM.
Did you read this with maptools::readShapePoly? Try with rgdal:readOGR
so you get the projection automatically with the object.
I cannot download the data from the link you provide, but if you post
the text
Hi Migun:
Do an str(nc.river)
Is the proj4string string set, please?
Thanks,
Erin
From: Migun Shakya [microbea...@gmail.com]
Sent: Monday, February 25, 2013 7:45 PM
To: Hodgess, Erin
Cc: r-sig-geo@r-project.org
Subject: Re: [R-sig-Geo] converting from NA
Hi Erin,
I tried that but ended up getting this error. Does the spTransform
function requires the data to be as data.frame?
Here is what i did to read the data
library(maptools)
library(rgdal)
nc.river<-readShapeSpatial("~/hydromaj/hydromaj_arc.shp") #reading the
shape file
nc1.wgs84 <- spTransfo
Tom, say x is your SpatialPolygonsDataFrame, did you try the obvious,
as(x, "SpatialLinesDataFrame")
?
On 02/25/2013 11:18 PM, Tom Roche wrote:
How to cast SpatialPolygonsDataFrame (SPDF) to SpatialLinesDataFrame
(SLDF), or vice versa? Alternatively, how best to write a function to
use either
On 02/25/2013 11:00 PM, Adrian Antonescu wrote:
Hi,
Two weeks ago I have asked a question regarding the use of R for plotting
lightning density maps. Thanks to you answers I was able to go one step further.
Attached is the .R script and a sample of the data. The script is counting the
number
Hi!
Suppose your data set is called nc1.df.
Then you can do:
library(rgdal)
nc1.wgs84 <- spTransform(nc1.df,CRS("+proj=longlat +datum=WGS84"))
From: r-sig-geo-boun...@r-project.org [r-sig-geo-boun...@r-project.org] on
behalf of Migun Shakya [microbea...
Hi all,
Is there a way/package/trick to convert the NAD83 formatted file to
lat lon format?
I downloaded the "Major Hydrography" dataset from NC,USA to plot
rivers into a NC map. However, the dataset is in NAD83 or in state
plane projection, but i need it to be in lat/lon.
Any help would be gre
Dear Michela,
I apologize for the late answer. From the help of mahasuhab, section "Details":
?mahasuhab
The function ‘mahasuhab’ first computes this mean vector as well
as the variance-covariance matrix of the niche density function,
based on the value of habitat variables in th
How to cast SpatialPolygonsDataFrame (SPDF) to SpatialLinesDataFrame
(SLDF), or vice versa? Alternatively, how best to write a function to
use either an SPDF or an SLDF as a map overlay in levelplot(...)?
Why I ask:
https://bitbucket.org/tlroche/clm_cn_global_to_aqmeii-na
regrids a dataset from
Hi,
Two weeks ago I have asked a question regarding the use of R for plotting
lightning density maps. Thanks to you answers I was able to go one step further.
Attached is the .R script and a sample of the data. The script is counting the
number of lightning strikes in hexagons, and then is plott
On Mon, Feb 25, 2013 at 2:12 PM, Jonathan Greenberg wrote:
> Folks:
>
> Has anyone figured out a general solution to create a foreach progress
> bar, updated as each iteration is completed?
>
> --j
The following is what I use frequently, but you should note that the
raster package (assuming that'
Folks:
Has anyone figured out a general solution to create a foreach progress
bar, updated as each iteration is completed?
--j
--
Jonathan A. Greenberg, PhD
Assistant Professor
Global Environmental Analysis and Remote Sensing (GEARS) Laboratory
Department of Geography and Geographic Information
Folks:
After about a year of working on this package, I finally got
spatial.tools pushed out to CRAN this weekend. The core function
(?focal.hpc) provides an engine for realizing parallel/cluster
processing of raster files with some features to make the development
of the functions easier for use
On 02/25/2013 02:24 PM, ping yang wrote:
Dear R,
I have a question for conducting a spatio-temporal inquiry, suppose I have
a time series of air temperature data for 100 years for my domain, can I
perform a inquiry like this " *How many days are there temperature above 40
degree *(CC) and get
Dear R,
I have a question for conducting a spatio-temporal inquiry, suppose I have
a time series of air temperature data for 100 years for my domain, can I
perform a inquiry like this " *How many days are there temperature above 40
degree *(CC) and get all these days", I noticed there are evolving
Hello,
I am working with spacetime data of pollution (91 stations, 193 time).
With the new release of gstat, i was able to compute a good sample
variogram (thanks :-)).
But now I would like to now if there is a way to visualize our data
set in order to be able to define a good Space-Time ani
if your data are latitude/longitude, and you specified them to be so
(i.e., is.projected(object) is TRUE), then distance is in km, else
distance is in the units of the original data coordinates.
(I recognized your output to come from gstat::variogram, but please
mention such details in future
when computing variogram, what are the units of the dist in the output
below. are they in km?
np distgamma id timelag spacelag
2 90855 1.148903 42.10353 lag0 01
3 114349 2.929328 40.82177 lag0 03
[[alternative HTML version deleted]]
_
Dear Ross, no you missunderstud.
The area of a (square) pixel is computed by a^2 where 'a' is the length
of one pixel side.
In your case a^2 = 100 qkm (and a^2 = 1000 qkm in the second case).
So if you want 'a' from your area's you have to make sqrt(100[km]) and
sqrt(1000[km]), the result is th
23 matches
Mail list logo
