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

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1
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0answers
73 views

Divide polygon based on points for even distribution

If I have a point layer, how can I create a polygon that includes all of the points and divide that polygon into n sections in which each section contains an equal number of points? Preferably in ...
3
votes
0answers
111 views

How to perform Shapefile to Raster with ArcMap 10.1 while preserving resolution and values?

I am new to ArcMap and I would really appreciate some help. I want to create a new raster using a value in a column of a point shapefile. I have a point shapefile with points equally spaced and each ...
6
votes
2answers
99 views

Finding lines in point patterns?

I have a point pattern (see below) in which I assume to find "significant" lines of points. However, I did not find any method that is integrated in a GIS or in R that searches for such line pattern ...
0
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1answer
145 views

Offsetting Points by location

Sorry If you've read this before - I've tried to change the content so that it reflects what I need a little better. This question was marked as a duplicate although I read the the answer to the other ...
6
votes
3answers
2k views

Is there a way to label points in a regular interval in ArcGIS 10?

I'm working with lines on roads represented by a large number of sequencial points. Since labeling all of them would make the points impossible to identify, I'd like to know if there is a way to label ...
2
votes
1answer
95 views

How to convert a line to points?

I'm working with QGIS and I want to convert a line into many points, does someone know how? Thanks.
3
votes
2answers
257 views

How to do a Point to Polygon analysis with multiple variables?

I have a database of almost 10k crimes, which are divided in to 10 categories and plotted on a map I also have a database of 12k addresses, which are also plotted on the map. I aim to perform a ...
0
votes
0answers
47 views

Uploading transmission line shapefile into spatialite.

I merged around 70 different transmission lines shapefiles of a state into one. Then, with a grid I divided the state into many features and got the centroids in QGIS. I'm trying to calculate in ...
2
votes
1answer
82 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 ...
2
votes
1answer
285 views

Find projection of a point to a line

I have a segment defined by 2 LatLon points(A and B) and a third LatLon point (C). I need an alghorithm, formulae, or some code to find the projection point of C on the segment AB (call this point D) ...
13
votes
4answers
10k views

How do I create point features with exact (manually entered) coordinates?

How do I create point features with exact (manually entered) coordinates i Quantum GIS (QGIS)? I get precise gps coordinates from a survey team which I need to add to a point layer. What I want: -Add ...
0
votes
0answers
35 views

QGIS adding points using decimal degrees [duplicate]

As duck blind permits are sold, we need to add the location using lat/long. we are working in ArcView now but would like to move to QGIS- Everything I was able to find seemed to deal with importing ...
0
votes
2answers
145 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 ...
1
vote
1answer
182 views

Arcpy Error 999999: Error executing points to line. Coordinates or Measures are out of bounds

I am selecting two points from a table and then doing a points to line function. I was originally getting this error because they were multipoints with multiple locations. I ran Multipart to Single ...
1
vote
2answers
358 views

QGIS create layer with the points of the beginnings and ends of a polylines layer (without duplicate points)

In QGIS, i would like to create a new layer containing the beginning and end points of a polylines layer, but without the duplicate points that would result of adjacent polylines.
0
votes
1answer
569 views

How do I write a MYSQL spatial query to find all polygons (rectangle) that contain any points in a table?

Something like: SELECT * from polygons WHERE bounds CONTAINS(SELECT geom_point from points) Can someone help me out with the syntax? Bounds will always be a rectangular polygon and everything is in ...
0
votes
0answers
71 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 ...
3
votes
1answer
169 views

How to determine error radius of given points

I am running QGIS 1.8.0 on a 64-bit Windows 7 platform. Given multiple points with different (but close) coordinates, how do I automatically create a new point that programmatically takes into ...
1
vote
2answers
539 views

How to select all points within a circle in PostGIS?

I have set of points in a PostGIS Table (Type Geometry). Now, I need to filter points that lie in a circle with a center (C) and radius (R)! I expect C to be of type Point or Coordinates.. R to be ...
6
votes
4answers
4k views

How do I convert a polygon into a point?

I want to convert polygons into points. I know how it's done in ArcGis and I think this may sound trivial but it's a serious issue :/. I'll appreciate any hints :)
0
votes
2answers
413 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 ...
16
votes
2answers
3k views

How can I find a point inside a polygon in PostGIS?

How can I find a point that is guaranteed to be within a given polygon in PostGIS? I am aware of the ST_Centroid function. However, the centroid is not always within a polygon, see below: ...
4
votes
2answers
282 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 ...
0
votes
1answer
177 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 ...
1
vote
1answer
65 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
110 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
35 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
288 views

How to find the nearest single point?

I have two shapefiles containing each one set of points, set A and set B. One set is my random selection (set A), the other is a list of communities (set B). For each point of the random selection ...
0
votes
2answers
215 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: " + ...
5
votes
4answers
1k 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 ...
0
votes
1answer
70 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
1answer
36 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 ...
1
vote
0answers
100 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
251 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 ...
5
votes
3answers
216 views

Methods for lat/lon quality control?

I have a database with fields including latitude, longitude, city, state, and country. When mapped, it is clear that a number of the sites are in the wrong location - most commonly because of a sign ...
0
votes
1answer
90 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
119 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 ...
4
votes
1answer
481 views

Is it possible to create a point within a Polygon (not a centroid)?

Is it possible (without writing Python code - sorry I'm not a developer) to create a point layer from a polygon layer but ensure the point is within the polygon? The ftools centroid tool is cool but ...
2
votes
1answer
108 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 ...
3
votes
0answers
70 views

Adding points to represent non-chosen locations

I am looking for a way to set up a discrete choice model in ArcGIS for foraging behavior of individuals, in a grid of 15 locations. To do that I need a point for every possible choice they could have ...
0
votes
0answers
14 views

how to create several buffer around 1 point with attatched distance information (qGis) [duplicate]

hello guys, I need to know how to create several Buffer (like isochrones) around 1 Point (the distribution center). The buffers should include a distance description. For example the first Buffer ...
5
votes
2answers
759 views

Creating a line (closest vertex to line)

I am working in reorganising our utility data. Two years ago, we have started collecting Private Service water line. We still have a lot of them to extract from old Record Drawings. I was ...
3
votes
1answer
179 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 ...
1
vote
1answer
166 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 ...
1
vote
0answers
280 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
230 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 ...
6
votes
2answers
693 views

QGIS or Postgis - How to split polylines with a point layer?

In QGIS, I would like to split the polylines in a layer loaded in the workspace with the points in another loaded layer. If a point intersects a polyline, this polyline should be transformed into two ...
0
votes
0answers
228 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 ...
0
votes
0answers
423 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 ...
2
votes
1answer
45 views

Is there a way to represent multiple attributes of a single point feature with icons?

I always wandered 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 ...