# Tagged Questions

(1) abstract geometry; (2) storing geographic data in projected coordinates; (3) a generic ESRI term for vector features; a class for "geometry" objects.

292 views

### Geopandas: counting the number of raster pixels within a shapefile polygon

I have a shapefile that I have loaded as a geopandas dataframe, and it has a geometry column containing polygons and multipolygons. My end goal is to do some zonal computations on a GeoTiff raster, ...
186 views

### spatialite : spatial index on geometries

I'm currently learning to use spatial access methods for query optimization. I'm going through the examples in spatialite cookbook and got stuck in here http://www.gaia-gis.it/gaia-sins/spatialite-...
211 views

### Create point on a line with given distance from end in PostGIS

Does anyone know how to create points along a line (MultiLineString geometry) with a given distance in PostGIS? I'd like to create points at a regular distance over a line, which represents a ...
357 views

### Efficient way of determining polygon intersection with bounding box

I have a set of polygons, and I need to check whether they are intersecting with a given bounding box(rectangle). What I am doing is, I am taking every vertex of polygon and checking whether it's ...
2k views

### Google's S2 library - any alternatives? [closed]

Is there any alternative to Google's S2 geometry library? It looks it was updated 4 years back and hardly any documentation. I need a library to divide cities into zones of the area I need. S2 looks ...
65 views

### Creating PolylineZ in arcpy

The script below is slightly modified "Polyline example" from ArcGIS help http://resources.arcgis.com/en/help/main/10.1/index.html#//018z00000008000000 import arcpy # next 3 lines are new from arcpy ...
102 views

### How to get arcpy to access attributes of a geometry?

As a novice python programmer I am struggling mightily with my code. What it is supposed to do is Buffer a bunch of points with four distances (100, 200, 300, 400meters) Calculate zonal sum for ...
1k views

### How to convert features of layer from POLYGON to MULTIPOLYGON?

How can I convert features of a layer from POLYGON to MULTIPOLYGON? I know how to do that using the postgis function ST_Multi but how could I do to same thing for a layer in QGIS?
196 views

### Using arcpy to find geometry within another feature

In Arcpy, I would like to start with a point and then using its geometry method to find out if it is inside my polygon feature (Urban Areas) deeper than the buffer distance. This is a follow up to ...
71 views

### How to know if two geometric figures are approximately equal?

I would like to know how to determine if two geometric figures (the_geom) are approximately equals. By the way, I'm working with Python, PostgreSQL and Postgis I have the following geometries: ...
1k views

### Using WKT.writeGeometry for 'Circle' Geometry in OpenLayers?

In my application which I'm building using OpenLayers3, I'm trying to extract the geometry of a feature to WKT using var format = new ol.format.WKT(); console.log(format.writeGeometry(geometry)); by ...
127 views

### Drawing boundaries between discrete features based on attribute values in ArcGIS for Desktop?

There is a point feature class with a certain numeric attribute (let us say, populated places with population). I wonder if there is, in ArcGIS, a way to draw polygons such that the sum of the ...
62 views

### Zonal geometry output in ArcGIS

Is there a way to specify the coordinate type in Zonal geometry output in ArcGIS? I am trying to perform zonal geometry on a raster and in the resulting output, the XCENTROID and YCENTROID are in ...
100 views

### Joining the tables with the geometry

I have a large table (as a shapefile without geometry, just set of records) with data which has the refference to the other tables (as a shapefiles with specific geometry, reference as same ID's for ...
62 views

### How can I find internal overlaps in my polygon feature class ideally via modelbuilder tools?

I have a polygon layer containing "depth curves" for the making of a skin of earth kind of map. I want to check whether or not my feature class contain any overlaps internally between these polygons. ...
123 views

### Points contained in envelopes that cross date-line - java

I'm using the ESRI Geometry Java API https://github.com/Esri/geometry-api-java I want to construct an envelope and see if it contains certain points. It's possible the envelope crosses the ...
93 views

### Reverse parameters of a projection map

I'm user of a soaring simulator named "Condor Soaring". This simulator is at the center of a community of enthusiastic people who build sceneries (landscapes) which represents quite accurately real ...
64 views

### Unable to read different kind of shape files

I have written the java code to read the shapefile and insert it into the table. But the way I have written code it will accept only a multistring .shp file. It fails for other shapefile geometry ...
3k views

### Store a GeoJSON FeatureCollection to postgres with postgis

I am new to GeoJSON. I have a GeoJSON features collection as shown and would like to store it in postgres table (testtable). My postgres table has a serial id and geometry column. { "type": "...
283 views

### Calculate distance between two points in projection EPSG:900913

I have two points in 900913 projection and I want to calculate the distance between the points. I don't want to transform points to 4326 and then calculate. How do I do this?
143 views

### QGIS Python - raster as point layer, coordinates issues

I would like to create point layer for storing values retrieved from a raster file. My idea was to iterate through all raster cells. If cell value is different than NULL, I wish to create a new point ...
107 views

### Could not translate dgn geometry to esri fgdb

I am trying to import geometry in dgn file to a point feature class in arcgis file geodatabase. I have a layer in dgn file 'baum' which bascially means trees. I want to store these features in CAD ...
2k views

### How to add a point to existing attribute record, rather than edit attributes of an existing point?

I'm using ArcGIS 10 to create point data. Normally I would start an edit session, select point as a construction tool, click where I want a point to be, and then go in and edit the attributes. Say I ...
337 views

### Extracting specific geometry point from MultiPoint geometry using PostGIS?

I am working with multipoint geometries in postgis and would like to extract the geometry point associated with the greatest y value of the multipoint geometry. How may I accomplish such a task? For ...
140 views

### TSQL Geometry Query Requires conversion to string

If I specifically define some polygons and check for containment, I get a correct result: DECLARE @g geometry; DECLARE @g2 geometry; SET @g = geometry::STGeomFromText('POLYGON((407305 100826.5, ...
347 views

### Convert string column back to geometry column?

I had a table with a column set to 'point' in doctrine2, but this was changed to 'string' and updated. I can't change it back to 'point' in doctrine2, I get an error: [Doctrine\DBAL\Exception\...
80 views

### Geometry in QGIS 2.6

This might be a beginners question, but I could not find an answer on the internet. I drew a couple of polygons in a vector layer and I am trying to get some basic geometric information into my ...
161 views

### Postgis: Query ST_DWithin in square instead of circle

The ST_DWithin query queries all geometries within a certain radius from another geometry (in my case a point). For performance optimization of my application I want to query in a square. So that the ...
288 views

### How to handle coordinates accuracy in ArcGIS

I am creating very basic rectangular polygon using very basic a Python code nCols,nRows=100,100 corners =[[0,0],[0,nRows],[nCols,nRows],[nCols,0],[0,0]] p=arcpy.Polygon(arcpy.Array([arcpy.Point(*...
33 views

### problem in PostGIS Name of the system used for Points and how to get distance between to point?

I have started to work on a project in PostGIS. I have a table with a geometry points in which points saved like this : "010100000089F511C671C01E4162327E2A83545341" and I have translated this ...
221 views

### Parsing large GeoJson geometry to WKT

I'm reading a very large json file as an InputStream in Android with JsonReader. This json has a geometry object like so.. "geometry":{ "type":"MultiPolygon", "coordinates":[ ...
118 views

### JTS Geometry to GML3.1 encoding

I searched all the internet and I didn't find a solution to my problem. I want to convert a JTS geometry to a GML3.1 geometry. Geo tools says that have support but the have not (please check encode ...
794 views

### Convert java.vividsolutions.jts.geom distance to meters

I am using com.vividsolutions.jts.geom to perform the distance calculations. I have a list of "LineString"s and a Point (Say A). I want to determine the The nearest LineString to the Point A. The ...
23 views

### Creating density layer after calculating one value based on two variables?

I have a map of census blocks and the population of each block for an island. I also have a map of the tax map key (TMK), broken down into land parcels, with the dollar value of each land parcels. I ...
142 views

### ArcGIS geometry update from table XY

I am trying to update the geometry of a point FC stored in a FileGeodatabase using ArcPy. I got this Python script to compare the values of the SHAPE@X and SHAPE@Y and change the Geometry if not ...
314 views

### Calculate distance from all points to all lines within 10km using FME?

I have a polyline shapefile and a point shapefile. The points are along the polylines. There are over 100 lines and over 10,000 points. I want to calculate the perpendicular distance from every ...
145 views

### Inflating the boundaries created with convex hull

I have a set of lan and lat points and have plotterd a convex hull for them using QGIS. A polygon is created along the set of points and plotting them on the MAP. Now I am trying to inflate the size ...
940 views

### How to compute Straight Skeletons using Python?

Is there a Python package which provides an implementation of a Straight Skeleton algorithm? I'm aware that the open source (C++) project CGALcontains an implementation but it seems like cgal-...
935 views

### Openlayers 3 ol.extent to ol.geom.Polygon conversion

In openlayers 2 there was a method "toGeometry()" on Openlayers.Bounds() that could convert that bounds into a Geometry. I migrated from ol2 to ol3 and I try to find a solution to easily do the same ...
112 views

### How to use Calculate Geometry tool to calculate area

I have added a field in my attribute table but I cannot calculate the area. The units field is greyed out and the options at the top say "area - disabled". What can I do about this?
27 views

### Points shapefile resulting in MultiPoints table in PostGIS

I have a Points shapefile. When opened with QGIS, the type is 'Point' (right-click on the layer and check properties). When imported in PostGIS using pgAdmin III plugin 'PostGIS shapefile and DBF ...
209 views

### ArcMap: Output to XML Including Shape Data?

I need to create a solution for non-technical people to export data from an ArcMAP document (.mxd) to XML files. I will need each feature's data to be exported in such a way that the output xml file (...
84 views

### Is there any way to know if a polygon is part of another bigger polygon(s) in SQL server?

Basicaly, what I am trying to do is we have a lot of geographical containers like territories, sub-territories etc. and the boundaries of each keep on changing all the times and I have to store the ...
284 views

### Intersection point of polygon and the line created by two points ArcPy

I have polygon layer. I selected the most distant vertex from centroid (picture: point A). (How to do that is in the answer here: Select the most distant vertex from polygon's centroid using ArcPy)...
514 views

### How to calculate the Oriented Bounding Box (OBB) of a polygon or point set?

I'd like to calculate the "Oriented Bounding Box" (OBB) which is the enclosing rectangle aligned to the longest extent of a point set (which is not necessarily aligned with the axes of the co-ordinate ...
226 views

### Select the most distant vertex from polygon's centroid using ArcPy

I have a poligon and the polygon's centroid. I want to select the most distant vertex from centroid (picture: point A). I used arcpy.FeatureVerticesToPoints_management to create a feature class ...
1k views

### Order sql server spatial geometry distance by the nearest

I have a geometry column in a table, I want to get the N nearest neighbours; here is a specific example with the geography type DECLARE @PTO Geography = Geography::STPointFromText('POINT(-57.432546 -...
3k views

### Choosing SRID and what is its meaning? [closed]

I'm new to GIS, in PostGIS, and I'm struggling with the SRID concept. How do you choose a SRID for a database column? This is making me crazy. Why do I need to choose a SRID? What's its meaning? ...