Questions tagged [geometry]

(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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21 views

Polygon visibility with overlapping polygons QGIS 3.4

I am marking forestry boundaries over google satellite tiles. The forest in question has areas of farmland within the outer boundary. One area of farmland has a patch of forestry within it's ...
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1answer
28 views

Collecting geometries and selecting attribute-value using QGIS

In QGIS, I have a polygon-layer with communes. Some communes consist of different parts (exclaves). I want to merge all parts of the same communes to one object. How is it possible to define which ...
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23 views

Selecting the SHAPE column in Toad

I've noticed that SQL clients select the SHAPE column from SDE.ST_GEOMETRY in different ways: Toad: SDE.ST_GEOMETRY(1,1,666666.0,4444444.5,666666.0,4444444.5,NULL,NULL,NULL,NULL,0,0,300051,(BLOB)) ...
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0answers
39 views

Distance between centriod of the polygon and each and every point of the polygon [on hold]

I'm trying to calculate the distance between centriod of the polygon and each and every point of the polygon using GeoPandas Python I need to find the distance between centroid(18.9568383649 72....
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1answer
28 views

Checking feature overlap using ArcPy cursors

I have a set of geometries that I want to check whether they touch another geometry. I have created a tuple "tiffs" where I want position 0 when touches is true. tif[0] and tif1 are strings. The ...
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1answer
22 views

Transforming geometry points coordinates to WGS84 in geodataframe

I have shapefile that has been brought into my script as a geodataframe. Initially, it shows no crs although the source originally had a datum = NAD83. I want the coordinates for the geometry (the ...
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4answers
451 views

Symbolise polygon outline where it doesn't coincide with other feature using geometry generator in QGIS?

I would like to symbolise a polygon without converting them into a line. I have a polygon feature (hatched and bounded by red line) which coincides on top and bottom of the coastline (blue line). I ...
2
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1answer
132 views

How do I use pre-existing Lat/Long data in a SQLite table with QGIS?

I have an application that stores its data in a SQLite database. I can't modify the application or database to add geometry extensions, but it does already have latitude and longitude columns for each ...
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0answers
33 views

Identifying convex and concave portions of polygon using ArcMap

I have a polygon shapefile depicting an island. For my study, I'm interested in two coastal features of the island: convex sections (portions of the coastline that extend into the ocean) and concave ...
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0answers
20 views

PostGIS - Measuring the angle at the touching point of two lines

I want to calculate the angle of two lines of a routing network exactly at the "touching point" (the topological vertex). My previous attempt was using the ST_ANGLE() function of PostGIS, which gave ...
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41 views

Counting points in polygon containing holes using QGIS?

Basically, I have these area (part of a bigger map) containing many holes (e.g. lakes) I have thrown on the map some 1000 random points and I want now to count those that fall in that area. I already ...
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1answer
63 views

Find nearby points in space and time

I have a table that has an ID, point geometry and time. It's basically GPS coords and some other data. I want to be able to select all rows that interact (come close in space and time) to my target ID....
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1answer
20 views

Add geometry attributes tool in ArcMap successfully runs but no fields are added to attribute table

I am attempting to add a line bearing attribute column to my shapefile in ArcMap. I'm using the Add Geometry Attributes tool to accomplish this. Running this tool is successful, however when I inspect ...
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0answers
27 views

How can I easily determine the precision of an OGR geometry?

I'm writing a python tool to update some river catchment boundaries and keep running into geometry errors, such as WARNING: TopologyException: Input geom 1 is invalid: Self-intersection at or near ...
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2answers
40 views

Deleting several features from shapefile using ArcPy? [closed]

I recently started working with ArcMap and Python. I try to delete several objects from my shapefile in ArcMap. I would like to select for example the line which are too close together. I don't want ...
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0answers
31 views

QGIS: Update geometry via geom_from_wkt('POINT(X,Y)') - how to correctly parse string columns?

The columns containing X and Y strings look like -1234,56 So far i tried: geom_from_wkt(concat('POINT(',replace("wbr_komplett.X",',','.'),',', replace("wbr_komplett.Y" ,',','.'),' )')) and also: ...
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2answers
51 views

Making New Feature Class with Midpoint of Line Feature using ArcGIS Desktop?

I have a problem with creating a new shapefile ( for Points) with a midpoints from Line shapefile. I cannot use FeatureVerticesTo Points_management because I only have access to Basic and Standard ...
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1answer
96 views

Creating 3D geometry column by combining existing 2D geometry column with “elevation” column?

I want to create a table that contains 3D data. I currently have 2D data stored as EWKT, which is multipoint geometry in one column, and another column that has elevation from sea level in another ...
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1answer
53 views

ST_IsValid and duplicate vertex

I expected to get 'false' from the following statement: SELECT ST_IsValid(ST_GeomFromText('POLYGON((0 0,10 0,10 10,10 10,0 10,0 0))')); Instead it returns true! Even if the vertex in 10,10 is ...
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31 views

WFS-T geometry name problem OpenLayers

I am sending my modified features to database with transactional WFS. The problem is when I render my vector features on map their property name which describes geometry is changed to 'geometry' and ...
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0answers
21 views

GDAL osgeo for python treating Z dimension differently

I have a space defined by a polyhedral surface, and I would like to check if a point is inside this space, and I would like to do this in python with gdal. After trying the default installation of ...
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0answers
7 views

(DSAS) Baseline won't Transect Appended Shoreline

I am trying to Transect my "Baseline" with my appended shoreline using DSAS in ArcGIS version 10.3. But this message window keep popping up every time I transect ( see attached first photo). Its ...
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0answers
39 views

QGIS: check and repair geometry

I'm studying how to check and repair geometry correctly and found the "check geometry" tool which seems to work fine. However there are also tools called "check validity" and "fix geometry" which ...
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0answers
29 views

Check geometries in QGIS for multiple KML Files all at once in R or Python? [closed]

I am very new to GIS analysis so please bear with me. I have 2000 KML files. I am currently using QGIS Check Geometries function to generate the error report that consists of the following. A CSV ...
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0answers
25 views

What closeness measures are appropriate to this undirected graph?

I need a way to measure the closeness centrality of every single NODE(i) in respect to all NODES(j), 1 NODE(i) to all NODES(j) and, another measure that describe somehow the geometric properties of ...
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0answers
20 views

Creating planar rectangle about points of interest in Google Earth Engine?

If I have a list of points of interest in Google Earth Engine, e.g. var pointList = [ ee.Feature(ee.Geometry.Point(-73.96, 40.781)), ee.Feature(ee.Geometry.Point(6.4806, 50.8012)) ]; var ...
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0answers
52 views

Pros/Cons of using 'ellipsoidal' for calculating geometry in QGIS?

When I have found geometry attributes in the past, I've found my distances are often out by quite a lot unless I use an ellipsoidal CRS to calculate them. Why is this the case? Should I be using ...
2
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1answer
69 views

Optimising Large Spatial Queries in SQL

I'm sure similar answers have been given elsewhere but no matter what I have tried I am unable to optimise this query. Details: TableA has 3.5mill records TableB Had 57000 records but I have ...
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1answer
41 views

ArcPy UpdateCursor fails when adding a transform to SHAPE@XY due to type error

I have a Feature class with 285k point features. I am running this code on it: with arcpy.da.UpdateCursor(FeatClass, ["SHAPE@XY"]) as cursor: for row in cursor: cursor.updateRow([[row[0][...
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1answer
31 views

Measuring area covered by linestring

I have a trajectory given by GPS which I store as a ST_LineString() and I'd like to know the area covered by the line string. I know the "width" of the trajectory, but I'm not sure how to approach the ...
2
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0answers
60 views

Applying filter on the geometry for a given feature?

I have multiple layers, with multiple features, where I am interested in extracting information from a given feature within a rectangle. I am able to achieve this using the following filter, ...
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0answers
30 views

MMQGIS Export error

I have set up some 1 KM grids via a country Shapefile and I want to get the coordinates of the four corners into a CSV file. I am using MMQGIS (QGIS plugin) and I'm trying to run a geometry export to ...
2
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1answer
65 views

Difference between $x and x($geometry) [closed]

I just stumbled across something weird: I had point-data in EPSG:3059 and wanted to add the coordinates to the attribute table using $x resp. $y - which returned NULL. x($geometry) on the other hand ...
2
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1answer
51 views

Making polygon shapefile from unsorted point shapefile?

I have a point Shapefile with unsorted feature ID's (FID). I want to convert the same point file into polygon Shapefile by using python gdal/ogr. I got the help from link1 and link2. I'm able to make ...
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2answers
48 views

arcpy Polyline.within(Polygon) returns False for all lines between pairs of Polygon vertices?

I'm trying to develop a function which will find the longest straight line length that can be drawn within any of the polygons in a feature class. (To keep things simple, I'm only including lines ...
1
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1answer
62 views

Problems with dissolving layers [QGiS 3.4.1]

I am currently working on a set of data that defines restricted areas for use of photovoltaic modules. This set of data amounts to 270.00 polygons in total [with their own geometry]. For simpler ...
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4answers
175 views

Calculating polygon's length along a line?

I need to calculate the length of polygons along / projected on a line. An image to show the idea: I have thousands of polygons to be "projected" on lines to verify how many meters of the line they ...
1
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1answer
17 views

Splitting lines: Options for managing IDs and related records

I have roads in a feature class (Oracle 10.3 geodatabase). Roads are split into separate lines where they intersect. This is an established business rule that cannot be changed. Each road has ...
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0answers
70 views

SQL Server spatial data geometry type

I'm trying to link a GeoServer application to a SQL Server Spatial Database. The spatial data has been saved as Geography, but GeoServer can read only Geometry type. So I'm using the following script ...
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2answers
62 views

Updating Z coordinates of points in polygons with ArcPy

I am trying to update Z values of polygon shape with ArcPy. This script is working without error but increasing the first (0 position vertex) vertex twice. I want to update only once. How can I avoid ...
2
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1answer
31 views

Shapefile export of holes geometries in QGIS with wrong type MultiPolygon

I want to export a layer with holed geometries in it. But when I save my features to shapefile in QGIS 3 it creates a file with MultiPolygon as geometry type. The fact is that a holed polygon isn't a ...
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0answers
21 views

Editing errors in shapefile

qgis version: 3.4.9-Madeira I am editing a shapefile. I want merge two adjacent polygon. Then, I run merge tool, and it comes like below picture. You can see some gap(?) or tail shape line between ...
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1answer
54 views

Update Z values of polygon veritices with multiparts and donuts [duplicate]

I am trying to update Z values of the vertices of the polygon shape. The script bellow works for polygons without multiparts and donuts. If I run this script for polygon shape that contains multiparts ...
2
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2answers
43 views

FME spatial join by PointOnAreaOverlayer transformer rejects Invalid Polygon Geometry Type

I would like to perform a spatial join of points and polygons in FME Workbench by PointOnAreaOverlayer transformer. The result should be a country polygons with additional attributes from points. I ...
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0answers
35 views

Connect to Enterprise GDB in PostgreSQL using QGIS : “No Geometry” Error

I have an esri Enterprise Geodatabase (9.3) stored in MSSql 2008 with storage type as sde binary. I upgraded it to EGDB 10.4.1 (using multiple up-gradation steps) in MSSql 2012. Then I copy/paste my ...
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1answer
52 views

Updating Z values with geometry of multipart and donut polygons with ArcPy?

I am trying to update Z values of polygon features with point features. The code is (found on GIS Stack Exchange) working good if no 'interor ring' or 'multipart' features are present in the polygon ...
1
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1answer
42 views

Extracting Oracle geometry with FME's SQL Executor transformer

I am wondering why my SQL executor can't extract the geometry from my Oracle database. The geometry are polygons. I added the 'SHAPE' column to the query in the executor, and I exposed the attribute ...
2
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0answers
53 views

Calculate the length of geometry line object using python in QGIS

Calculating the length of a geometry line object using the Field Calculator gives you 2 options: $length where the length calculated by this function respects both the current project's ellipsoid ...
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1answer
28 views

Correct area calculations: When to use planimetric, when ellipsoidal?

Sometimes I am not sure whether to use planimetric or ellipsoidal model to calculate areas of polygons. If there is a "reference" data (e.g. a given shape_area column) I compare results and take the ...
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2answers
57 views

Invalid geometry after gdal.polygonize

After converting a raster file to a vector file using gdal.polygonize, I cannot carry out further commands (e.g. Clip) because the vector is produced with invalid geometries (as determined by the QGIS ...