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

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1answer
118 views

Is it possible to draw polygons along Google Maps Polyline?

Web application has option that user draws polyline on Google Map. After he draws it, there is a button 'Add polygons', which should draw polygons along that line, based on some width and height in ...
0
votes
1answer
198 views

ST-Links convert Feature Class to DB Table error

I'm using ArcMap with the ST-Links SpatialKit Conversion tool to convert a Feature Class to a DB Table. But I'm getting an error: ERROR: 42601: type modifier is not allowed for type "geometry". I ...
35
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4answers
7k views

What are the pros and cons of PostGIS geography and geometry types?

My company uses geometry (the_geom) data type for storing geospatial data. I've recently been acquainted to the concept of geography (the_geog) data type which, as I understand it, stores the SRID ...
1
vote
1answer
286 views

SQL Data: How to draw circles with a radius based on lat/long data in DB

I have a . sqlite file with many columns, two of those columns being lat and long. I've been searching around for a bit now (don't think I want to be using BuildCircleMbr from spatialite?) but I'm ...
0
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2answers
27 views

MS Sql Server 2012 UnionAggregate geometry fails in ArcMap

I have following two geometries. Geometry 1 (G1): MULTIPOLYGON (((148.134707676 -34.1519003565, 148.143738823 -34.1540810687, 148.14648294 -34.1396863245, 148.143196834 -34.1392361445, 148.140859243 ...
4
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1answer
308 views

Radius of curvature for curves in road segments for entire road network

I have a road network shapefile for a US state and I am trying to derive the radius of curvature for road segments in this shapefile. I need to be able to perform this task within just a few functions ...
0
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1answer
304 views

SQL Geometry Query similar to Select by Centroid

Does anyone know if it's possible to query SQL geometry by something like 'centroid of polygon'...similar to ArcMap's select by location? I'm using SQL Server 2008 R2 as the DBMS. I have two polygon ...
0
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1answer
21 views

add featureset in graphics layer without iterating

I have a geoprocessing service that returns a large amount of features (featureSet). I want to attach them in a graphics layer, but I dont wont to iterate over all them. I tried using the ...
9
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2answers
377 views

What is the precision of SELECT DISTINCT on PostGIS geometry column?

I wonder what the precision of the SELECT DISTINCT operator is on a PostGIS geometry. On my system, the following query gives me a count of 5, which means that the inserted points are considered equal ...
0
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2answers
178 views

Calculating minimum/maximum width for overlay of two polygon strips in ArcGIS or some Opensource GIS

Is there some solution for calculating minimum and maximum width for overlay of two polygon strips? When I clip these strips the result is another strip with variable width about 1 km and 20 km long. ...
3
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1answer
27 views

How to save shape file as type 1 point file in Qgis?

QGIS saves point shapefiles as type 8 - Multipoint as default. I need QGIS to save as type-1 Point file. How?
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2answers
40 views

Ensuring SRID on geometry column in PostGIS

I am using a table that has a geometry type column called "wkt". Its definition in the table looks like this: create table sometable ( ... wkt geometry not null, ... ); I want to change it ...
14
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6answers
6k views

Converting between Esri Geometry and WKT using ArcObjects?

It seems like there is no means of converting an ArcObjects geometry to the Well-Known Text representation (and vice versa) in ArcGIS ArcObjects API. The only thing I was able to find is conversion to ...
2
votes
1answer
108 views

How do I use code (preferably c#) to clip all points within a shapefile that are not contained within a polygon?

So the task is simple: I want to take a point shapefile as input and remove all of the points that are not contained within a polygon. I'm using DotSpatial to do this, but the catch is that there are ...
4
votes
4answers
609 views

How to fix quickly a lot of geometry validity errors in QGIS?

I am working on ownership data at a US county level. I have one shapefile per county that contains thousands of tax parcels. I need to dissolve the polygons representing parcels owned by the same ...
2
votes
2answers
783 views

How to convert Geometry type column to degree Minutes Second in SQL Server 2008 R2

I have shape column of type geometry and I want to convert X and Y coordinates into Degree Minutes Second format using SQL query and i am using sql server 2008 R2. Currently I got Lat and long using ...
3
votes
1answer
93 views

Find gap in / endpoints of linestring

I have a set of features of type linestring. I'm trying to polygonise the linestrings and assumed that they were closed (naive me :) ). Of course some were not closed and I'm trying to locate the gaps ...
1
vote
1answer
50 views

ArcGis label last vertex Z value

Is it possible to label a feature in ArcMap using geometry values? In this instance I want to label features (polylines) with the Live Z value of the last vertex obtained from the Shape. However ...
1
vote
1answer
112 views

Get geometry from OpenLayers.Control.WMSGetFeatureInfo JSON

I need to store the geometry of a certain feature with OpenLayers.Control.WMSGetFeatureInfo and i'm using these parameters to get it in json format output:'features', infoFormat:'application/json', ...
2
votes
1answer
99 views

QGIS crash when I try print geometry

I do (it works): from osgeo import ogr inputds = ogr.Open(r'c:\temp.shp') inputlyr = inputds.GetLayer() for i,feature in enumerate(inputlyr): print i, feature.GetGeometryRef() Output: 0 ...
0
votes
2answers
133 views

Invalid geometry message when using Difference tool

I am using the Vector \ Geoprocessing \ Difference tool to get the resulting area when taking a) current ground disturbance away from b) historic total ground disturbance to give c) what has been ...
0
votes
1answer
110 views

Is it possible to have measurements in centimeter and decimeter in 2D flat (geometry)?

Is it possible to have measurements in centimeter and decimeter in 2D flat (geometry) for ArcGIS?
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0answers
41 views

Array to Feature Class and XYZ to Table Issues

I am trying export vertices of a line to a point feature class using the code below. I am using ArcGIS 10.2.2 and do not have access to Spatial, 3D, or Network analyst. I used ET GeoWizards to export ...
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1answer
30 views

Why are my points offset when using the Go to XY tool?

I am creating points in ArcGIS 10.1 to add to a GPS so I can navigate to them in the field. I add my points by editing an empty shapefile created in ArcCatalog. I then Add Field: Lat and Long as ...
1
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1answer
45 views

How to save changes in Feature-Geometry with GDAL/OGR and Python? (Segmentation fault)

I have a problem with my code: driver = ogr.GetDriverByName('ESRI Shapefile') dataSource = driver.Open('merge.shp', 0) if dataSource is None: print 'Could not open file' sys.exit(1) layer = ...
1
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1answer
32 views

Defining polygons based on thickness maps using ArcGIS for Desktop?

I want to find and create polygons that demarcates three different inflection points in a thickness raster: where the thickness start to increase, where the thickness is at its max and where it starts ...
0
votes
1answer
33 views

Convert geography to geometry in H2GIS?

In H2GIS, geometry can be converted to geography with function "ST_Transform" For example: SELECT ST_Transform(ST_GeomFromText( 'POINT(584173 2594514)', 27572), 4326); -- Answer: ...
1
vote
1answer
48 views

How to calculate distances in QGIS field calculator?

So I'm using qgis 2.6.0 and I have a csv (converted into a .shp) with two geometry columns, I want to create a new column with the distance between the two geometry: shot.lat shot.lon haul.lat ...
0
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1answer
27 views

Adding geometry.type circle

I have to amend the following code so that on the map it's possible to draw a second circle graphic as well as a line, polygon and point. I've tried to add an else if statement much like the polygon ...
64
votes
15answers
20k views

What are Definition, Algorithms and Practical Solutions for Concave Hull?

Convex Hull A convex hull of a shape is defined as: In mathematics, the convex hull or convex envelope for a set of points X in a real vector space V is the minimal convex set containing X ...
0
votes
0answers
27 views

Metrics of change between vector datasets

I have an old and a new set of parcel data which I'm looking to compare. I'm looking to compare changes in individual parcel geometries, so boundary/corner adjustment. Currently each parcel we have ...
2
votes
1answer
73 views

Use arcpy to check whether feature class geometry has ZM

I am looking for a programmatic way using arcpy to determine whether or not a feature class (FC) has Z and/or M geometry. It's easy enough to get the geometry type using the code below, but this just ...
1
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1answer
24 views

Is averaging the points for lines and multilines a valid method of getting the centroid?

I'm working with a SqlGeometry SqlServer DB and am a novice to GIS. I'm tasked with getting the centroid of a series of geometries from C#'s SqlGeometry object. This is fine as it has a GetCentroid ...
1
vote
1answer
45 views

How to import geometry data from csv file to postgres?

I have geometry file in *.xls file, but when I save in *.csv it say "some feature in your workbook might be lost if you save it as CSV (Comma delimited)" however I keep that file anyway and when I ...
0
votes
1answer
126 views

Get the vertices on a LineString either side of a point (Sql Server 2008)

I have a point that sits on top of a LineString, both Sql Geometry types. POINT('0.5 0.5') LINESTRING('0 0 NULL 1, 1 1 NULL 1') I want to find the vertices of the LineString that lie either side ...
1
vote
0answers
14 views

Needing to find parent zip code of a bunch of missing zip codes in the US

We're using MapPoint to export zip code / territory combinations. Unfortunately, the export doesn't include PO Box zip codes which mean that we're missing a lot of zip codes The PO Box zip codes are ...
0
votes
1answer
34 views

table update w/ cursor geometry conflict

I'm creating a table using arcpy with a list of results (stored in 2d lists) following an update to some features. This can sometimes include geometry, so I've attempted to substitute those for a ...
3
votes
0answers
30 views

What is the area that OGR extracts from the (geometry) shp files for polygons?

The ESRI July 1998 technical documentation for polygon shapefiles at page 10 makes no mention of either area measures or length measures (apart from byte/record-layout matters). Yet OGR enables me to ...
3
votes
1answer
69 views

Gaps and overlaps appear after cutting a previously topologically clean shapefile?

I'm using QGIS 2.2 and I have a polygon shapefile which was created by someone else. I have managed to get the shapefile to a topologically clean state by running v.clean but when I tried to cut the ...
3
votes
3answers
90 views

Drawing some points in QGIS 2.4 using Python

I'm new to PyQGIS so here goes: Give a new QGIS project, how can we draw some Points on the map? I tried the following but nothing showed up. Should they be placed in a Vector layer before they can ...
0
votes
2answers
118 views

How to store lat/long in PostGIS database? [duplicate]

I have a bunch of points in a text file that are represented using lat long (116.3158516 39.9748016). I import them into my GIS enabled database and create trajectories using st_makeline() as ...
2
votes
0answers
47 views

QGIS : cannot change the z-coordinate of a point shapefile using the wkb geometry format

I am using QGIS Desktop 2.5.0-Master with GDAL/OGR 1.11.0 on a windows 7. I am working on a little pyQGis script that should modify the z-coordinate of points in a vector shapefile based on a value ...
0
votes
1answer
775 views

Can variable be set to reference in_memory workspace object in ArcPy?

This is an offshoot question related to a question I posted earlier. I have the following arcpy code that inputs a Python list of polygon geometry objects to the Union_analysis tool, which then ...
1
vote
0answers
36 views

QGIS 2.4.0 doesn't support multiple types of geometry in GML file

I'm testing GML 3.2.1 data according to INSPIRE Data specification (version 3.0). Data for theme Cadastral Parcels shall have both polygon geometry and definition point. When I download data from my ...
0
votes
2answers
67 views

Count the number of points in a (multi)polygon in shapely?

I'm using Python, Shapely and Fiona to process some shapefiles. Is there an easy way to count the number of points in a polygon/multipolygon in Shapely and Fiona?
4
votes
0answers
64 views

how to compare geometries (contains, within) in arcpy?

I am trying to use 2 geometry objects to check if a line is within a (rather complex) polygon. The geometry check always fails, even if the line is clearly within the polygon. I use the following ...
0
votes
1answer
32 views

Add Marker on the polygons' centre using Openlayers?

I have written a code to draw polygon from the WKT format.Now I need to add the marker at its centre. In the following code I have passed the centre and shape in WKT format(extracted from database). ...
2
votes
1answer
88 views

How to get the width and height of a rectangular polygon in PostGIS

I have a table with point features saved in the my PostgreSQL database, and I can run the following query to get the extent of the point features and I turned the extent back into a geometry: SELECT ...
3
votes
1answer
70 views

Extract longitude latitude and radius from POSTGIS column

I have entered the circle in the Geometry type column (name=shape) in my POSTGIS as following: ST_Buffer(ST_MakePoint($longitude, $latitude)::geography, $radius)::geometry Then I extracted the ...
1
vote
1answer
60 views

PostGIS get geometries within a radius of n meters using WGS84 [duplicate]

select * from zones z where st_intersects(z.geom, st_Buffer(ST_SetSRID(ST_Point(2.336031, 48.863172), 3857),1)); It looks like the 1 in the st_buffer is being interpreted as degrees, I need to find ...