A geometric element defined by a pair of x,y coordinates.

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5
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1answer
111 views

How to connect centroids of lines sharing the same intersection in QGIS?

I'm looking for a big help to accomplish the following task: I have this street network of the center of Turin (IT), composed by lines representing streets, and black points representing ...
5
votes
1answer
312 views

QGis 1.8 fails to rotate point geometries with rule-based style

I have to do some visualizations in QGIS (1.8.0) and up to now I've been very happy with the new Dialog "Layer Properties -> Style", using the rotation-field to rotate Point-Geometries visualized by a ...
3
votes
1answer
155 views

How to map flood areas from a set of points containing surface and height of water?

I am working on the damages made by the typhoon Haiyan. I use QGIS 2.0 with extensions and toolbox, and MapInfo. I have vectors, rasters of the place. I want to map the flood area along the ...
2
votes
1answer
47 views

Is there a better way to convert Raster to Point data? Don't need one point for every cell

I need to convert raster data to point data so I can use the points for interpolation via kriging. My problem is that my resolution is 5 ft and I'm working on a whole city. The data I am converting ...
2
votes
1answer
103 views

How to find the polyline's ID connecting two points in ArcGIS 10.1?

I have an ArcMap (*.mxd) file with several layers including a point layer and a polyline layer. The points are connected by polylines in the polyline layer, and I wish to know how to list the ...
2
votes
1answer
305 views

Getting null values using Point sampling tool in QGIS 2.0.1

I would like to obtain the information of a raster layer at some points. Apparently the Point sampling tool does the job. I have used this tool, and all the raster values extracted at specific points ...
2
votes
1answer
379 views

How to obtain closest point of point over polylines layer in PostGIS 1.4 (without st_ClosestPoint)?

I´ve got a polylines layer (pipes) and a points layer (valves) and In Postgis 1.4 I would like to obtain the closest points but exactly on the closest polyline. In other words, i need to locate each ...
1
vote
1answer
26 views

Merge 2 Pointlayers with same coordinates but different attributes in QGIS?

I have two layers with points who have exactly the same coordinates but different attribute fields. I would like to merge the tow layers so that I only have one point at each location who has the ...
1
vote
1answer
50 views

Why did my data points shift position?

Here is an example of my issue: There are two point layers displayed in this image: The yellow dots are my currently used layer with the most updated data. The green dots are legacy data from when ...
1
vote
1answer
53 views

Select points near polygon in Postgis

I'm trying to make a spatial query, but I think something is wrong with it: I have two tables, places (point) and cities (polygon) When I try to get the points within 500m to one point, there is no ...
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0answers
317 views

ArcGIS10 Split Line at Point Failing due to Dataset size

Im having an Issue with my Split Line at Point tool. Seems to run if lucky for 700 entries before arcmap/arccatalog falls over. Debugging of the errorlog has produced nothing. The total size of the ...
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478 views

Error creating IPoint (ArcGIS 10) - Invalid use of New keyword (VBA)

I have some code I wrote in 9.3 that (mostly) works in version 10. I have a UIToolControl that buffers a user-input point based on a mouse click - nearly identical to the sample. This used to work ...
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0answers
74 views

Point features disappear when adding new data

Recently while adding features to a point layer i noticed that once i had saved my edits the already existing points disappeared. Although not visable on the map all of them and their data were still ...
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0answers
407 views

Moving GPS Points with a VB script - Bearing works well but distance is wrong

I am using a script I found online created in 2003 by one of the commentators here. It is a great script and exactly what I have been looking for and I'm very glad to have found it. It simply takes ...
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0answers
279 views

getting the correct location data with user input

I have some code others have provided, which I modified in order to run a Python script in a toolbox in ArcMap which accepts user input for a starting point, distance, and angle to create a shapefile ...
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0answers
16 views

Order a list of points to make a polygon with smooth outer border

I have a function that pulls some lat/longs from a Database and then I put those values in a polygon to see it's shape. The problem is they are so random in position and direction from each other that ...
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21 views

Why does the “local maxima” module in SAGA GIS put so many “maxima” points on lakes and plains?

SAGA GIS puts too many maxima points on plains and lakes. Why does it happen? Is there a way to avoid this? It's not really a big problem (the value is correct) except for the size of the SHP files in ...
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0answers
31 views

Extending line by adding point at end of it using QGIS?

I'm using QGIS 2.8 to modify a line. I need to add a point on one end of this line, and then move this new point further away, leaving the original end point in the same place. I can manage to create ...
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0answers
13 views

Point data aggregation for choropleth

I have a sizeable amount of geotagged point data (>1M) and am looking to create a choropleth map of point data density based on boundaries I have in a shape file. I've added this to a fusion tables ...
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18 views

Temporal correlation of point data

Case: I am working on a project where we are trying to study the correlation of municipality water leaks with diseases, we have a geo-referenced database of water leakage reports and disease reports, ...
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0answers
22 views

Raster to point: 10 rows in the attribute table per 1 point

I have just made Raster to Point operation. In the output, if I select a point on the map, in the attribute table appear I have just selected 10 rows. How is it possible? Where, in the Raster to Point ...
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25 views

New value in attribute table for big amount of points

I have got a huge amount of points. I need to change their value according to thier current value. Ex. I have got 4000 points. 1000 with value 7 and 3000 with value 8. I have to select all those 1000 ...
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29 views

How to convert points distribution toward surface information?

I'm working with QGIS 2.6 I have a points layer representing different bus and train stops. I applied a categorized symbology; each colour represents a class of value (field regarding time access ...
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0answers
18 views

Assign Nodes ID to Polylines in QGIS

I want to consolidate data from various layers into a single layer so I can export it for use in an external software program. I am interested in how to selectively combine data from different ...
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0answers
10 views

Creating a point in a fixed distance and course

How can I create a point in a fixed distance and course from an existing point using the Microsoft SQL SqlGeography object ?
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31 views

Point to Raster Converting Result

I had a problem with Point to Raster converting result. I had an Excel file which contains x, y and z values. I wanted to create an individual raster data from classified z values so I planned to use ...
0
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0answers
62 views

What's the best way to convert points to raster and back again?

To convert raster grids to vector points In QGIS there we have different possibilities (grass tool "to.vect"; saga tools "grid values to points"). My problem is a little bit complicated. In the ...
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0answers
31 views

How to map data from USGS NAS database, using HUC?

I am querying the USGS NAS (Nonindigenous Aquatic Species) database. The collection data for the results that are returned don't include lat/long points, but have an HUC (Hydrologic Unit Code). I have ...
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35 views

Parameters for CreateFishnet

I´m about to create a fishnet. The CreateFishnet tool has several parameters, between them the origin_coord - The starting pivot point of the fishnetl. Data type of this parameter is Point Now there ...
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12 views

Pavement survey implementation

I know I am supposed to be specific...BUT I am working as part of a research team on pavement study. I need to visually display survey data in Arcmap. The surveys consist of x transverse ...
0
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0answers
97 views

How to convert geometric point to geographic point in SQL Server?

I am new to sql geometric and geographic types What I need is a way to convert a sql table of geometric points into geographic points?
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69 views

export qgis point symbols per feature

I am currently trying to export the drawn symbol in a QGIS map for a webmap. The current approach is to extract the properties: if i.rendererV2().dump()[0:6] == 'SINGLE' and i.geometryType() == 0: ...
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42 views

Reading Points as PolyLines

I'm currently developing an Android app where I need to show some information on a map, which is stored as Shapefiles (.shp + .shx + .dbf). I noticed that when the shapefile is opened in QGis, a nice ...
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52 views

QGIS Rasterization of points

I have a point vector layer and want to make it a raster. Trouble is that many points are very close to each other, so unless I specify a very small resolution of the raster cells, likely several ...
0
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0answers
91 views

how to remove a point or polygon in shapely python

I want to place minimum number of sensors(circles) to cover a maximum area(polygon). I am using "Shapely",python module. I want to know if a sensor i.e a point buffer inside the range of the other ...
0
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0answers
85 views

Can I create a cross section from points along a line without using a DEM in QGIS?

I have a set of points perpendicular to a river and would like to present a cross section of them. Like a simple graph in Excell for example, with Z as y axis and distance along the line as the x ...
0
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0answers
314 views

Can't zoom to feature from Datagrid with ArcGIS API for JavaScript

I have a find task in my application that returns features that are points, lines and polygons. I can get the search to populate the datagrid but I am having problems with my onRowClickHandler ...
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0answers
83 views

Use python to execute GRASS module v.distance

I have successfully use python script to import a line shapefile and a point shapefile into GRASS, and the following are their attribute table in QGIS, line shapefile point shapefile Now I want ...
0
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0answers
145 views

PyQgis: How can I “append” features to a Vector Layer instead of “stacking” them?

As I read data from a text file and add points to a QgsVectorLayer (as well as related attributes), each new record gets 'stacked' on top of the previous one in the Attribute Table (and within the ...
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55 views

Split polygon into four with respect to single point

Some days ago one of my colleague came to ask me a query related to Geometries. The situation is as....There is one Polygon(suppose a city polygon) and there is one point(suppose user's current ...
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63 views

Reducing point numbers in a certain area

We have a list of poi data in our database(Access mdb db), and we have a web service which serve data by a specified BoundingBox. However we found that the returned points are too close to another at ...
0
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0answers
49 views

How to create a point representing a polyline?

How do I convert a line (usually 2 vertices but can be more) into a single point in QGIS? I did it a couple of years ago using a build-in tool in ArcGIS 8 or 9 I think but have no idea how to do it in ...
0
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0answers
100 views

Point features disappear when moved using QGIS 2.0

When I move, either by the node or the move function, a feature symbol on the map canvas, it simply disappears, not just the label, the whole thing. CTRL-Z brings it back. I'm using a MAC OS-X. I've ...
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0answers
143 views

Building real-time point/polyline connection in GIS

In the first instance I need to create the network by constructing the basic elements, the nodes and links. This is relatively easy work as SharpMap has provided geometry tools that allow users to ...
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0answers
135 views

Create shape file with point

I am trying to create a .shp file with Point shapes. I am following this tutorial: http://docs.geotools.org/latest/userguide/tutorial/feature/csv2shp.html I create the project, no syntax error and ...
0
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0answers
110 views

How to convert a set of points to a polygon based on a specific field in QGIS

I am having a point shapefile that consists of a number of point sets. I need to convert these points to a polygon based on a particular field in attribute table say for example locality . How can i ...
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488 views

Bearing Distance to Line tool from dBASE table only draws one line in ArcGIS 10

I am using the Bearing Distance To Line tool to draw geodesic lines to points defined by a bearing and distance. This is an aside, but I will then use the Feature Vertices To Points tool to convert ...
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250 views

Splitting a TAB file by attribute?

I have TAB file with LOADS of points. Each point as a unique ID and group assigned to it (ranging from 1-154). I'm wondering if there is an easy way to split this up into a TAB file for each group, ...
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57 views

How to format spreadsheet to input point data for later import to PostgreSQL

I want to create a spreadsheet to hold data from our cemetery. I will use the spreadsheet to get the data into a PostgreSQL database. What I dont know yet is the format that the point (positional) ...
0
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0answers
476 views

How to do a spatial join if QGIS 1.8 keeps crashing?

I am trying to perform a simple spatial join (adding polygon data to points) in QGIS 1.8: target vector: points join vector: polygons take attributes of first located feature keep all records ...