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

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0
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2answers
195 views

Python Delete point in a distance of x meters

I took this code from this source Select maximum number of points more than x meters apart It seems to work for other users, but for me it's an endless loop. I do not understand why, though the code ...
0
votes
2answers
720 views

PGROuting 2 : Getting nearest node to a given point (with lat - long given)

I have a point whose latitude and longitude (only) are known, and a table of nodes with their geom. I want to find the closest node in the table to the given point. I think I can achieve this with ...
3
votes
1answer
66 views

How many polygons under a point (ArcGIS solution preferred)

Opposite of Point in Poly. How many polygons underneath a point. I have a point layer with many points. I have a polygon layer with many polygons. I need to add an attribute to the points that ...
0
votes
1answer
319 views

ArcPy Create Point Along Line A Specified Distance From A Specified Point

In ArcGIS Basic I am trying to take a road polyline(one segment for the entire length of road) and get a point placed on the map a specified distance from an intersection. I have a layer of ...
0
votes
2answers
540 views

Using NetCDF for point time-series observations?

I have a large growing dataset of water and climate observations for several years in regular hourly time-step. The number of locations is cca. 1000 locations with latitude, longitude coordinates. At ...
1
vote
1answer
67 views

point shape file problem

I have a point shapefile which was created from a text file in Excel using the delimited text layer plugin in QGIS. My problem is that I am getting a point shapefile but when i try to insert this in ...
-3
votes
1answer
129 views

How to create a polyline feature from a point layer

I would like to create a route line based on a point layer. The existing tool does not meet the customer requirement. But using the code snippet below, the start point and end point are always the ...
1
vote
1answer
40 views

How to handle a UnicodeEncodeError with sampling tool?

I'm using qgis and I keep getting an error when using the point sampling tool, its keeping me from getting the sampling done. Does anyone has an idea what is it about? Thanks!
2
votes
1answer
97 views

Calculating point proximity in ArcMap 10.1

I have a geocoded point file which (theoretically) contains one point for every zip code in the U.S. I want to create a smaller list of zip codes from this file. The list should include only those zip ...
0
votes
1answer
217 views

Linked point geometries to linestrings in Spatialite

I have been parsing Canada's radio system frequency open data. It's a single large table per province, containing point geometries for each station callsign. Where a point-to-point link is defined, ...
1
vote
1answer
140 views

Sum of point attributes inside hexagons using QgiS UI

I'm very new to Qgis so I would very much appreciate any help you can give me. I have a point shapefile that corresponds to locations of animals captured. I've joined a table to this shapefile with ...
1
vote
1answer
37 views

How can i display the color of my labels into the content table?

The thing is that i need to display labels based on colors but without the symbol. In this case i'm working with points in Arcgis 10 and the maps needs to display only labels with color-based ...
4
votes
2answers
402 views

How do I find the average distance within a polygon to a point?

For my purposes, I can assume a homogeneous distribution of points within the polygon. What I want to find is the average distance from points within a polygon to a specified point. I don't know where ...
1
vote
0answers
125 views

WMS: point “pointer” symbol with offset - getFeatureInfo search area slight mismatch

I'd like to ask what ways there might be to adjust a point's getFeatureInfo search area so that it matches a "pointer" (i.e slightly offset) symbol. We are running GeoServer 2.2.0 (part of an Opengeo ...
4
votes
2answers
411 views

How to draw lines from two points in a CSV?

I have a CSV file where one line looks like this: Duration, user, lat-start, long-start, lat-end, long-end 298, Casual,38.9101,-77.0444,38.91554,-77.03818 Each row in the CSV has two points and I ...
0
votes
1answer
120 views

interpolate point values to line

This might be a stupid question and I apologize if so. I have count data for different trails. They are points and I would like to make an average of those counts for each trail so that each trail has ...
2
votes
2answers
133 views

How to add attribute in shapefile guidedly

I have a point layer (31 by 31 grid = 961 points) created by fishnet tool > feature vertices to point tool (but with duplicate points). NOx Concentration data are in an Excel file. I want to ...
2
votes
1answer
166 views

How to solve routes to offset points in Network Analyst?

The scenario is that there are points on a grid with intervals of 1000m covering an area of hundreds of square kilometres. I want to find routes on a road network to any one of these points. A road ...
1
vote
1answer
341 views

how to split a line by a point which is on the line but not in the linestring itself?

i need some help with the following: i have a linestring - geom i have $lat,$lon (using some php syntax) i have an osm table with the roads geom, i am trying to get closest point, and then split ...
3
votes
1answer
204 views

How to represent Typhoon(s) wind speed using Quantum GIS / PostGIS?

I am not completly new to GIS (was taught ArcGIS at Uni) but I would still consider myself (especially compared to all these experts here) a newbie in QGIS or PostGIS. I want to display the ...
2
votes
1answer
493 views

Better way to get raster values for a large number of point features?

I have several projects with tree point features (SpecialStatusSpeciesPoint) that contain up to 2,000,000 records. I am trying to record tree height (Hgt) and base elevation (BaseElev) values, based ...
3
votes
2answers
417 views

How to average values in a point layer with respect to polygon layer in QGIS?

I am new to GIS and have the following problem: I have 2 layers: a point layer with a column that contains numbers (pollution index from specific measurement point) and a polygon layer with different ...
0
votes
0answers
355 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 ...
2
votes
1answer
745 views

Getting polygon shapefile node coordinates and point order

I am trying to get the coordinates of each node of a polygon in QGIS. What I basically did is use the following tools: Vector -> Geometry tools -> Extract nodes Vector -> Geometry tools -> Export ...
2
votes
1answer
61 views

Representing multiple attributes of single point feature with icons?

I always wondered if there's a way to represent using an array of various icons multiple attributes of a single layer containing point features. For example, think about a point feature with these ...
0
votes
1answer
99 views

QGIS create point data attribute as the name of the polygon it falls in

I'm working in QGIS with a point data set overlaying a farm with 140 fields. While I can analyse the points from each field individually, I would rather use an awk script to calculate statistics I ...
1
vote
0answers
48 views

windows function with points in a mixed (multipoint/point) table

I have a table comprising multipoints (tracks) and points (stops between tracks). there can be several consecutive multipoints. now, i want to merge any points lying very closely to each other ...
2
votes
1answer
106 views

Is it possible to update only latitude or longitude in postgis ?

I have a postgis database that contains Points created based on a couple (longitude, latitude), and I need to update only one of those two for a given point. I found that it's possible to do so but ...
6
votes
5answers
2k views

How to create points in a specified distance along the line in QGIS?

I want to use QGIS creating points along the line, but in specified distance. I found two GRASS tools in SEXTANTE Toolbox: v.to.points v.segment I tried v.to.points, setting the maximum distance ...
1
vote
1answer
79 views

Counting points in a raster

Is there a way to select points in a raster dataset by raster classification? I have a floating point raster created from the points, classified into 4 ranges by standard deviation. I want to find out ...
2
votes
0answers
208 views

Divide polygon layer by point layer in QGIS?

I have two layers - one polygon layer that is a buffer of a road layer, and one point layer that shows certain locations along that road. What I want to do is to divide/split the polygon layer at the ...
4
votes
1answer
480 views

create grid cells of fixed dimension around a point acting as a centroid

I've been trying to solve a problem for the last few days but not having much luck. I'm hoping someone here can point me in the right direction. I'm new to ArcGIS so I hope my explanation makes ...
1
vote
1answer
812 views

PostGIS, create line from points

I have a PostGIS table with position data of numerous vehicles and want to create lines from these points. Data can be selected by vehicle id and ordered by timestamp but how to create lines from the ...
1
vote
2answers
212 views

How to select two points on a map using QGIS?

I need to select two points on a map in QGIS. I selected the element selection tool in menu view and I want to select two points. How can I accomplish this? Are there other tools or methods to ...
1
vote
1answer
1k views

Converting Points to Lines in ArcGIS AND retaining attributes of both start and end points

I have been searching and searching and I can't find a particular solution to what I need. I have a table with animal location points. I need to calculate movement distances between points from the ...
0
votes
1answer
73 views

Point to point distance over specified distance

I need to calculate the distance between neighbouring points which conform to a staggered line. I have two point datasets, one being the baseline and another the monitor. The points typically reside ...
0
votes
2answers
379 views

add a vector point on OSM map

I have managed to show Lat and Lon function init() { navigator.geolocation.getCurrentPosition(function(position) { document.getElementById('myloc').innerHTML="Latitude: " + ...
3
votes
1answer
99 views

How to delete points from CSV point layer?

I have a point layer produced from importing a Delimited Text Layer and I would like to delete some points. It seems that it is not possible to toggle editing in a point layer. How can I delete the ...
5
votes
4answers
653 views

How do I fill in serial letters (AA, AB,AC…,BA,BB,BC…ZZ) to a shape?

(I am using ArcGIS software, ArcMap...) MY PROBLEM I have a shape file containing points. The shape file contains 3 columns named FID, Shape* and Label. In the column I want to fill in AA, AB, ...
-1
votes
1answer
298 views

QGIS and Python - create line with multiple points in postgis [closed]

How can I create a line, with Python functions, with many points that are records in Postgis? Thank you
1
vote
2answers
544 views

Creating a 3D line feature based on 3D point features

In ArcGIS for Desktop 10.0, is it possible to create a 3D line feature by drawing a line that connects 3D point features?
1
vote
1answer
234 views

generate random world point geometries

I have a world map. I need random point geometry. So, how can I randomly generate point coordinates? Any programming language. Also, I am using SRID 4326. Any programming language.
0
votes
2answers
468 views

Joining Points and Polygons

I am new at using arcGIS 9.3.1 and am having trouble joining data. I have a shapefile of census tract polygons and a separate file of points that are crimes in Chicago in 2010. The crime points were ...
1
vote
1answer
208 views

random sampling from spatial points in R

Can anyone help me out on the best package to sample from a spatial point dataset? My dataset consists of a list of positions inside a region, and for each point I also have the name/number of the ...
1
vote
2answers
109 views

simplify point geometry

I have a great amount of points and I need to show them on map. I am using OpenLayers. Is it possible to simplify point geometry in order to speed up the process of rendering?
3
votes
1answer
1k views

Problems converting polygon to point [closed]

I'm trying to convert polygons to points with ArcGIS 10. My polygon layer has 2 attributes that I want to give to my point layer. I'm using the Feature to Point function from the Arctoolbox, but it ...
1
vote
1answer
318 views

Aggregate points with same values to polygons

I have a shapefile with 2M measurement points (each measurement point has a resolution of a 1/10). How can I aggregate points around each other if and create polygons out of it? They do not have to ...
1
vote
0answers
349 views

How to calculate average value within a polygon(in Qgis with Python)?

Now I have a point and polygon shapefile and I want to calculate the points' average value within each polygons How to do it with python? I tried to find out but google gives me a lot of raster ...
1
vote
0answers
98 views

Join .csv file and .shp of georeferenced points

I have georeferenced a map and saved a selection of some points on the map. These points are cities of departure and arrival and I want to join the .shp with a and excel .csv with the information of ...
3
votes
1answer
291 views

Convert polygons to a number of randomly located points based on polygon size

ArcMap 10.1 on a PC. Working with a large shapefile with ~50,000 poygons with a wide range of size from 1,000+m. to <1m. I would like to convert these polygons into points so I can do some analysis ...