3
votes
2answers
61 views

Reprojection of shapefile in R and final extraction of values

I need to extract values from some raster files (stack) using a shape file. to bring both of them in the same CRS, I first transformed the shapefile using the EPSG codes. Opening it in an GIS software ...
4
votes
1answer
64 views

Convert ESRI Shapefile to Raster using R - biggest polygon area to raster cell value?

I want to create a raster from an ESRI shapefile. Multiple polygons may exist in one raster cell. If so, I want to assign the attribute variable which occupies the biggest area of the raster cell. ...
2
votes
1answer
38 views

Intersect shapefile with raster, then determine proportion of each raster value?

Using the arcpy module in Python, I want to find the proportion of each pixel value within the boundary of an overlaying polygon. (The polygon is in a shapefile.) For example, there are 10 possible ...
1
vote
1answer
26 views

How to show number of patches in a neighbourhood?

Given one raster file containing only one zone that indicates patches of vegetation in a city and a shape file containing neighbourhoods for the city, explain how you could create a map that shows the ...
2
votes
2answers
67 views

Group adjacent polygons with similar (but not same) attributes

In ArcMap 10, I have a few dozen tiffs with cells that represent habitat area that has been burned. Each burned cell has a Julian date of the fire associated with it. I want to end up with polygons ...
2
votes
1answer
208 views

Mapnik + OpenStreetMap + Shapefile with Raster Images + Mod Tile + PostGIS

I am new to GIS. I have a Shapefile (.shp, .shx and .pbf). The .pbf file contains path to PNG files located on my machine only. I was able to save the Shp data to PostGis via Shape2Gis tool. Now ...
0
votes
1answer
43 views

Clip a shapefile based on raster extent with high accuracy

I am trying to clip a shapefile based on the extents of a smaller raster. I find the extent of the raster using this code: Extents = arcpy.sa.Raster(MyRaster).extent` Then, I use these lines to ...
0
votes
1answer
28 views

gdal_rasterize : getting area not in or touching polygon (options -at and -i)

I would like to capture the area that is not in a polygon (option -i) and that doesn't touch that polygon. gdal_rasterize -at will return the polygon + edges, but gdal_rasterize -at -i will not ...
0
votes
0answers
21 views

Overlay Shapefile and Raster layer in R [duplicate]

I have a raster layer with climate data from the north of Mexico, part of Canada and the US mainland. I am trying to restrict the climate data to only the zone of the US mainland. To do this I thought ...
2
votes
0answers
90 views

Ecoregions shapefiles: subsetting, extracting and summarizing data from raster

I am attempting to subset and project an ecoregions shapefile from : EPA ECOREGIONS my data set is found here: SHAPEFILES and RASTER When I run this code, two major problems occur: 1) I cannot get the ...
1
vote
1answer
110 views

extract shapefile attributes from raster colors

I have two layers: a shapefile with states and counties (shp) a raster file (with colors and some text and borders, but not a perfect map) (tiff) I want to use the colors in the raster file to ...
1
vote
0answers
72 views

How to create a circle vector layer with 12 sectors with Python and to save average value of underlying raster in each sector?

Hi I am writing a code with Python 2.7 using Arcpy 10.1 and I guess I am doing stuck with a silly problem that lies under my eyes. I have created a grid of points (with "Create fishnet" function) over ...
0
votes
0answers
33 views

How to raster vector- and shape-files correctly

does anybody know how to convert vector- and shape-files correctly? Doesn't work with tab Raster/convert/vector to shape files. The output always contains strange input-data (wrong and strange ...
3
votes
2answers
893 views

Extract Raster from Raster using Polygon shapefile in R

I am new to R and using the raster package. I have a problem extracting polygons from an existing raster file. If I use extract(raster, poly_shape) function on the raster it always creates a list ...
0
votes
2answers
78 views

Clipping a raster file into the multiple shapefiles

I splitted the single shapefile into the multiple shape file based upon their attributes. Now I want to clip the raster file into the each splitted shape file. How can I do it at once? I am using a ...
4
votes
2answers
168 views

Converting shapefile to raster: Character attributes

I've got a shapefile that I would like to convert into a raster, but the trick is that the attribute I want a raster version of is character data. I'm familiar with geoprocessing using GDAL (in the ...
0
votes
0answers
42 views

Android app where i can import image and set waypoints by GPS

Hello i'm looking for an application for android where I can upload a large image raster and apply for it `these GPS waypoints. We would like to count the trees in the area, we have the exact raster ...
1
vote
1answer
75 views

QGIS combine Vectorlayer and Rasterlayer to one shapefile

I have to create some Thematic Maps, especially Choropleth Maps on Matlab. Therefore i've found a shapefile which I can use, but need to draw some lines there. I've imported my shapefile as a Vector ...
0
votes
0answers
208 views

How to convert a shapefile to binary grid?

I have a polygon shapefile with a UTM projection which I read into MATLAB: s = 'C:\path\to\shapefile.shp' % Read the shapefile shp = shaperead(s); How can I convert this simply polygon into a ...
3
votes
1answer
167 views

How to count and rasterize polygon overlaps in QGIS?

I have a large number of polygons that are overlapping. I'd like to create a heat map and plan on using raster calculation to do this. My plan: to give each polygon a raster value of 1, and adding ...
1
vote
1answer
105 views

Load Raster Values into Shapefile [duplicate]

I have a shapefile containing many points. Some of these points fall within an area for which I have raster data. I would like to load the values of the raster which underlie each point into the ...
0
votes
2answers
90 views

Count the area of rasterdata in specific shapefile polygons (residential density in different districts)

I'd like to count the exact area of three different residential classes (low, medium, high) by district of a shapefile which contains 225 districts. like: district 1 has: XXX sqm low, XXX sqm medium, ...
0
votes
0answers
34 views

Can´t display two files at the same time

for some reason when I open a raster FIRST and then a shp, I can only see the raster. Then if I open the shp FIRST, and then the raster, I can only see the shp! Is there a bug on QGIS? Or have I ...
0
votes
0answers
26 views

calculating mean and standard deviation for raster values using whole pixels within a polygon [duplicate]

i have a raster image and a corresponding shape file. i would like to calculate the statistics of the values within polygons which have a common attribute but only using pixels which are fully ...
4
votes
1answer
78 views

Update Grid cell value with Point attribute

I have a 4km gridded dataset with each grid cell value as a measurement of precipitation. I would like to update it with a point shapefile of more precise precipitation values. Aside from ...
1
vote
1answer
672 views

How to change the pixel value of a raster dataset which overlaps a polygon featured shapefile in ArcGIS

I have a raster data of 1992 and a 'shapefile' of Los Angeles county. I want to reclassify the pixel value of the raster data set to 'no data' or zero in the region where the raster and the ...
1
vote
0answers
146 views

How to perform Shapefile to Raster with ArcMap 10.1 while preserving resolution and values?

I am new to ArcMap and I would really appreciate some help. I want to create a new raster using a value in a column of a point shapefile. I have a point shapefile with points equally spaced and each ...
4
votes
1answer
2k views

R - Plotting shapefile with geographical (raster) data

Over the last few days I have been trying to plot a shapefile over data loaded into a data.frame within R. It should be a view of radar precipitation with an overlay of the country borders from a ...
2
votes
1answer
123 views

Reproject gif.gz raster to WGS84 in QGIS

I am a steep learning curve into QGIS. I have a raster of global fire maps from the modis site: http://lance-modis.eosdis.nasa.gov/imagery/firemaps/firemap.2013221-2013230.8192x4096.gif.gz I would ...
0
votes
0answers
84 views

Why does a shapfile shift after transformation?

I have a shapefile created in the raster package (ER_14.3_2000_poly). > #read in a raster file > ER_14.3_2000<-raster('E:/Ecoregions Models/Outputs/ER_14.3/ER_14.3_ConsensusMap3.asc') > ...
3
votes
1answer
980 views

Setting extent and geographic projection in R

I have a raster and a shapefile that I am attempting to view and process in R. The shape file "ER_11.1" has the following specs: > ER_11.1 class : SpatialPolygonsDataFrame nfeatures : 22 ...
3
votes
2answers
343 views

How to calculate the shared area between a raster and a shape file in ArcGIS 10?

I have a raster file with 5 classifications developed from habitat modelling algorithms. I'd like to know how much of 2 classes of the raster is covered by the network of protected areas (Shape file). ...
1
vote
1answer
359 views

Problem to clip a raster with a shapefile

I need to clip a rasterlayer with a vector layer. When I try this, the following error appears: **ERROR 1: Attempt to create 0x0 dataset is illegal,sizes must be larger than zero.** What am I ...
3
votes
1answer
1k views

How to convert jpg file to shapefile? [duplicate]

I am developing a GIS application like this: By now my steps are: I have got a jpg file, 5040 x 8179 dimension. In this map, the roads, rivers, towns etc. are marked. I am using .Net to develop ...
1
vote
0answers
185 views

How to use GDAL to burn a selected value from one raster into another?

I think this should be a relatively simple process, but I'm not quite sure how to approach it. I have a shapefile containing 1000's of polygons. I also have 19 rasters. All of the polygons fall ...
2
votes
1answer
189 views

Tiling Rasters based on an existing Polygon Shapefile (Vector Grid)

I have a tile index representing the tile scheme used to tile Lidar data. I want to tile imagery rasters using the same tiling scheme. I have not found anyway using open source tools to tile a ...
3
votes
1answer
2k views

Creating Isolines from point Data

I'm quite new with ArcGis 10 so I’m having difficulties with something that may be simple to some. Anyway I have a list of bores that I’ve plotted using coordinates. Now I need to draw a single ...
6
votes
1answer
156 views

Is there a difference between projecting shapefiles then rasterizing & rasterizing shapefiles then projecting?

I currently have a project where I rasterize shapefiles into simple presence/absence (1 & 0) rasters and then add each one to a running total to create a total richness raster at the end. The ...
3
votes
3answers
226 views

How to compare a set of images with a shapefile?

I have around 150 images (rasters), each one is just a map of certain "classes", e.g. pixel value 1=forest. I also have a shapefile that consists of roughly the same area as the 150 images constitute ...
7
votes
7answers
2k views

how to overlay shapefile and raster?

I have a shapefile with polygons. And I have a global raster file. I want to overlay the shapefile's polygons onto the raster grid and calculate the mean raster value for each polygon. How can I do ...
4
votes
2answers
636 views

Extract all pixels of given RGB value and render as MultiPolygons

Given a geotiff image with a colortable in it, what is the easiest way to extract each color as its own "layer or shapefile or multipolygon object"? Specifically, I am looking for a programmatic ...
7
votes
1answer
5k views

Converting a polygon into a raster using R

I'm trying to convert a shapefile into a raster within R. My approach is to read in the raster as follows: library(rgdal) # Loads SP package by default demo <- readOGR('F:/data/', 'shapefile') # ...
0
votes
1answer
200 views

Where to get raster files of Earth, united states [duplicate]

Possible Duplicate: Open access repository of general GIS spatial data? I'm brand new to GIS programming so please excuse my lack of knowledge. I am developing a GIS web app using ...
8
votes
4answers
378 views

Identify corrupt shapefiles or rasters via Python or ArcObjects

I'm interested in a way to identify rasters (e.g., ESRI GRID format) or shapefiles that are corrupt that would prevent them from being used in an analysis tool. I have a large number in structured ...
14
votes
6answers
1k views

Creating simple image from vector data

Can anyone suggest a quick (and preferably open source) way to create an image from a shapefile. For example, I have a shapefile containing parcel boundaries, I want to create a png file depicting ...