0
votes
0answers
2 views

How to calculate a raster area with Grass - help for query by coordinates

I'm working with Grass. I have a raster digital elevation model and I have analyzed the wathershed flow. Now I have to: -calculate the watershed area; -find an identity in the digital elevation model ...
0
votes
0answers
8 views

How to find location from lon lat in shp file

I'm using openmap API to read SHP attributes file. So, How to get attributes of dbf file or layer infomation when I hover on map ?? thanks all !
1
vote
1answer
11 views

What's the purpose of the reference latitude in Lambert Conformal Conic?

Going through flight school I got acquainted with the Lambert Conformal Conic projection, as it's the common projection for VFR sectional charts, and I think I have pretty good grasp of it, ...
1
vote
1answer
9 views

Plotting species distribution on map in R

I'd like to plot the distribution of a species on a map of Switzerland, following this tutorial. library(maps) library(mapdata) map('worldHires', 'Switzerland', xlim=c(5, 12), ylim=c(45,48)) From ...
0
votes
0answers
6 views

Best practice for georeferencing coastline aerial imagery

I'm trying to georeference declassified CORONA images of coastlines in order to asses coastline changes and human impact. in most case, georeferncing is a no brainer, but since images of coastlines ...
0
votes
0answers
8 views

Hold a python variable during worksession

I'd like to get into qgis-plugin development, but am rather new to both python and qgis development. I intend to write a plugin which connects data from a mysql database to shapefiles. As the data is ...
-2
votes
1answer
16 views

SuperMap GIS in depth assessment

Does anybody have any idea about SuperMap GIS? --What are its limitations and strengths? --How does it compare to other GIS (especially ArcGIS)? --Can a local Government Department rely on it?
0
votes
0answers
5 views

Digitizing a city map for thesis project; Transportaion

So, basically I need a digitized map of a city that can be used for analysis. My thesis will be focusing on land-use destination, so I'll be needing the fully digitized map that has all kind of ...
0
votes
0answers
16 views

Shapefile to Rectangle Overlay/Intersect Test?

I have a shapefile and a repository of images that have corner Lat/Long points. I want to search that images who overlaps/intersects to shapefile. Here is the scenario that I am doing, creating a ...
0
votes
0answers
7 views

How to make a popup containing links?

I have a list of links taken from a GeoJSON file. What I want to do, is program a popup with all these links inside, with OpenLayers. So, I wrote a function which returns a string containing HTML ...
1
vote
0answers
17 views

Updating and exporting X and Y positions in UTM and WGS84 using ArcGis to a spreasheet with the model builder

On a daily basis I'm editing the geographic positions of various points of a shapefile (corner_XY.shp) by dragging them on my map. When this editing task is done I'm updating the points coordinates in ...
0
votes
1answer
17 views

What is the radius of earth [duplicate]

What is the real radius of earth? Google says 6378.1 km Wiki says 6371 km And there are references for 6378.7 km I'm using maximum radius 6378.7 km in distance calculation in spherical law of ...
0
votes
0answers
5 views

Trying to display GeoServer layer controls but nothing is coming?

I am a beginner with GeoServer trying to display layer controls but nothing is coming. <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>GeoServer Layer</title> ...
-1
votes
0answers
11 views

Get the specified feature by direction

I have two lines, while I want to get the line at the right hand according to a specified direction: The red line with arrow means the direction, while the line with blue color is the target to be ...
0
votes
1answer
16 views

removing spurious lines in raster before or after vector conversion?

I'm looking for a feature/function in either python opencv/ndimage/gdal/etc. or qgis/saga/grass that will help clean up a skeletonized image that I'd like to vectorize into a shapefile of ...
0
votes
0answers
23 views

How to combine Polygons and points?

Sorry for the basic question. I'm using qgis. I have two layers, one with points (a file that contains addresses with latitudes and longitudes linked to several variables), and another layer (a ...
1
vote
1answer
15 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 ...
0
votes
0answers
20 views

Statistics field in the dissolve tool not always accurate

When I run the Dissolve Tool using a Statistics Field (SUM being the statistic type) and proceed to check the SUM values for accuracy by comparing against the data in the original feature class, I ...
2
votes
2answers
27 views

QGIS doesn't create the correct projections when creating new shp files

I recieved shapefiles exported from ArcGIS with EPSG:2227 as the CRS, which should be: +proj=lcc +lat_1=38.43333333333333 +lat_2=37.06666666666667 +lat_0=36.5 +lon_0=-120.5 +x_0=2000000.0001016 ...
4
votes
0answers
28 views

How do ESRI and QGIS calculate scale values of geographic projections?

Does anyone know how (from which location) scale values are calculated in ESRI products and QGIS for geographic projections? The only thing I've noticed is that QGIS is changing scales when you pan ...
0
votes
1answer
18 views

Using ArcGIS Polygon to Raster tool does not divide resulting raster on cells?

I try to create raster composed of small (5x5 m) cells (pixels) from a polygon in ArcGIS-10. I created a polygon (as a single object), and use Feature to Raster Tool and Polygon to Raster tool (of ...
1
vote
3answers
26 views

Symbolizing multiple polygons as one by dropping internal boundaries?

Using ArcMap (ArcGIS 10.2 for Desktop), is there a way to symbolize two features within the same feature class as one feature without editing the feature and merging them? For example, if I have a ...
1
vote
2answers
113 views

How to calculate the square root of a feature attribute?

I have a polygon shapefile with over 16k features. Each has an attribute (Double, Precision(10) Scale (2)) that I am trying to calculate the square root of, and store in new field. Is there a tool, ...
0
votes
0answers
10 views

3D Analyst Extrude Between

I have a few TIN surfaces at different elevations, basically soil profiles, I've used the "extrude between" tool to create multipatch features. However, only one of the features says it is a closed ...
0
votes
0answers
16 views

Run-time substitution on MapServer with Leaflet

I have a MapServer instance and map file displaying data in selected countries using a Leaflet WMS tileLayer. This map file works to display points from a single country (showing the LAYER definition ...
-1
votes
0answers
21 views

GIS Seminars and Training [on hold]

I am trying to find a good website where I can find out when and where upcoming seminars and workshops will take place so I can plan for them with my work schedule. Does anyone know of where I should ...
2
votes
1answer
24 views

PROJ4 / PostGIS transformations between WGS84 and NAD83 transformations in Alaska

I'm trying to implement the recommended WGS84 - NAD83 transformation for Alaska using PostGIS. This post: Geographic Transformations in Alaska Between NAD83 and WGS84 indicates the proper ...
0
votes
1answer
19 views

When is Geographic Weighted Regression used and why?

I am currently trying to better understand what geographic weighted regression is, and what it is useful for. I have been reading up on it, but would like to get others people's views on it and see ...
1
vote
1answer
10 views

Geodetic lat/lon to ECEF cartesian: Direction to apply geoid undulation from ellipsoid surface?

I'm working on modeling the earths surface in 3D, using a combination of WGS84/EGM96 and NASA SRTM orthometric height data. To calculate a final cartesian XYZ coordinate for a point on the earth ...
-6
votes
0answers
37 views

What GIS processing machine is best to purchase if I have $5k to spend? [on hold]

I process huge data sets quite often. After expressing concerns with delays in project time frames, I have been given $5k to purchase a new PC. What should I get? I have built a couple machines on ...
0
votes
0answers
5 views

OpenLayers.control.Split not working as the example

I am following the split-feature example, but cannot make it works the same in my application. I have create a JsFiddle to show my code. In the fiddle you'll see a vectorLayer with one feature and a ...
1
vote
0answers
11 views

OpenLayers - Add points at vertices of line while drawing line

I would like to create points while I draw a line on my map in OpenLayers. That is, at each vertices of a line and at the end points there is a shape like a square, circle, or diamond. I have this ...
0
votes
0answers
9 views

Can HTML annotations be autogenerated for each location in QGIS 2.4

can HTML Annotation Boxes be autogenerated on the whole Map linked to locations and loading always the same html file for all of them? Best Regards
0
votes
0answers
6 views

ArcGIS Online:Unable to launch application: Unable to access application's configuration

I have a custom configuration for an ArcGIS Online Web Application, and have followed all instructions. I have changed the Web App settings and receive this message. Unable to launch application: ...
0
votes
1answer
7 views

Problems while rendering with Atlas

when I export my data genereated with the openLayers using Atlas rendering is always incomplete. Atlas is rendering too fast so that the data from openLayers is not completely loaded. Do anyone ...
0
votes
0answers
15 views

Calculate Solar Angle θs for remote sensing

Using the SPOT equation ρ = π L/[E cos (θs) d-²] to calculate TOA reflectance from Radiance. I have calculated d, L and Esun however I'm having trouble with cos (θs). SPOT says to calculate θs " ...
1
vote
1answer
23 views

ogr2ogr reprojection works on command line but shifts output when same command run from inside python?

Reprojection with ogr2ogr works fine on command line, but shifts the polygon to northeast when same command is run from inside python using os.system(...) Any ideas why this could be? I hard-coded ...
0
votes
0answers
36 views

Adding information from excel into ArcGIS [on hold]

I am working in ArcGIS and have a excel sheet with data pertaining to properties. I want to add this data to a map in ArcGIS of which i have property boundaries as a shapefile? I have a common folio ...
0
votes
1answer
12 views

How to delete selected features in Qgis using Python

I have a shape file with only one field DN. I would like to delete all features which does not have specific value of the field. Let say the DN can be 1,2 or 3. So far I was able to find out how to ...
2
votes
1answer
18 views

How to create a summary statistics table with as many rows as iterated features? I only get one row

I have a feature layer of 25 buffers, which are the light blue circles you see. Let’s call each buffer a community. Many buffers overlap. Each buffer has a unique ID. I also have a feature layer of ...
3
votes
1answer
66 views

ArcPy delete terrain: cannot be deleted

I can't get my ArcPy script to delete a terrain. If it exists, it should be deleted. However it throws an ERROR 000317: {path} cannot be deleted My script is a lot longer than this, but this ...
1
vote
1answer
20 views

JTS “points must form a closed linestring”

I'm trying to create a polygon and calculate it's area using final GeometryFactory gf = new GeometryFactory(); final ArrayList<Coordinate> points = new ArrayList<Coordinate>(); ...
1
vote
2answers
49 views

Creating counties in QGIS

I have a raster map (a photocopy I took from an Atlas), and a vector map of the UK. The raster map shows pre-1890 Scottish county borders. I have geocoded the map so that the raster borders overlap ...
0
votes
0answers
5 views

Updating an ArcPad Server Extension publication

If you have succesfully created a publication (axf file) that syncs between the server and multiple users, what happens if somebody wants to change the publication data, e.g. add some new fields ? ...
0
votes
1answer
14 views

How can i convert .tif file into headerless (flat) binary files?

I am using NDVI files (value range -1 to +1) created from Landsat CDR images to produce a timeseries in TIMESAT software. My .tif file has following characteristics. File type TIFF,Data Type ...
0
votes
1answer
15 views

resaving shapefile as WGS 84 EPSG:3857 doesnt align openlayer plugin

i am based in NSW, Australia. I have a shape file that when i underlay openlayer plugin (google satellite) the shape file is skewed despite all my efforts to correct it. I changed the project ...
0
votes
0answers
9 views

using WMS feature with OpenLayers object

I am sending query to a WMS address URL and getting results like following. data: { features: [...], totalFeatures: 2, type: "FeatureCollection" } I want to use features to calculate their ...
-1
votes
0answers
11 views

unable to open the QGIS Tab

I have download the QGIS Softarwe of “gis-osgeo4w-1.7.3-00624b3” and “QGIS-OSGeo4W-1.8.0-2-Setup” both from net and installed both in my system, My system is running window07 professional Service ...
0
votes
1answer
45 views

ArgGis seems to snap but doesn't

We are building a project in ArgGis 10.2 were we create buildings using rectangles. Some of them need to be attached at one or more sides (they have common walls), so we would use snapping to snap ...
1
vote
0answers
18 views

QGIS Equivalent of MapInfo's 'Combine Objects using Column' [duplicate]

MapInfo has a function that takes a table, and creates a new table populated combines them by a specified value. So, combining on the name field, and specifying that the Area field should be ...

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