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

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46 views

Authoring map with advanced gradient symbol for ArcGIS web service?

I need to prepare a web service which will display the gradient of polygon points values. It has to look just like in this picture: link to the picture (please ignore the arrows). Each polygon is ...
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2answers
103 views

I have a table with a series of lat/long points - how do I convert them into polygons?

I have an Excel sheet with about 150 points (lat and long in decimal degrees) which belong to about 15 different polygons. The columns I have are FID, NAME (the same between polygons), POINTS (points ...
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0answers
14 views

Where are the settings that control when clustering starts and stops?

We have a SDE set up on a SQL Server and we're using the Silverlight API. Our layer has buildings on it. The flare clustering and large clusters show when the map is opened and the actual buildings ...
2
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0answers
39 views

How to show coincident point with different symbology in webgis?

our team have develop an webgis using ArcGIS silverlight API 3.1 .we have some points in database.These points are save in a table in sql server 2008R2 not in Geodatabase.The points have same ...
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1answer
68 views

Multiply point values by raster values

I have a point shapefile containing elevation values in the id field. The shapefile is overlaying a raster layer of the topographical slope. Is it possible to multiply the elevation value of each ...
2
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3answers
121 views

How to identify concentrated areas with multiple point values to produce a “heat map” appearance

I have roughly 1.6 million points statewide with values ranging from 1 - 4. I'm looking to identify concentrations of points based on their values (1,2,3,4). I know there are several different routes ...
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1answer
78 views

How to compare multiple spatial point patterns over a polygon

I have multiple point pattern distributions over the same region/polygon. Each point pattern distribution has different number of points. Here is an example of two spatial point patterns for the ...
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1answer
87 views

Produce line from components, length and angle

I have a CSV file, or point data file which includes information about line vectors which I have previously calculated. This file is outlined as such: x, y, dx, dy, length, angle(east_from_north) ...
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1answer
100 views

Generating points from chainage and offset

I have a polyline layer and an external csv containing road sign data. The csv has unique ID of the polyline, chainage along each unique segment and an offset. I have access to ArcGIS, MapInfo and ...
2
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0answers
69 views

How to move points to another polygon based on attribute?

I have a point layer and a grid cell/fishnet layer. Each point falls within a grid cell. Now I want to move some of the points to another (the nearest) grid cell based on an attribute that exists in ...
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0answers
197 views

Splitting polyline by points using ArcGIS 10.2 for Desktop?

I have a layer containing a curved polyline and I would like to split it at multiple point locations, which I have in another layer. In ArcGIS 10.2, I can do this with the tool "Split Line at Point". ...
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25 views

Statistics on matching point layers ignoring nodata values in QGIS

I have a large area and a street crossing this area. Both are vector point layers in QGIS. The large area contains -99 as NoData value. I already created the intersection of both as a new layer. I ...
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2answers
158 views

How to convert a point layer to a raster grid that shows the frequency of points per cell in QGIS

I have a point layer that shows the distribution of a species. Is it possible in QGIS to convert this point layer to a raster grid in which the value of each cell corresponds with the amount of points ...
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1answer
48 views

QGIS hides few graduated points after reopening project

I have a strange problem in QGIS 2.2 (problem is also present in QGIS 2.1). When I add a point (shapefile) layer, apply graduated style and change point size, everything looks fine. Then I save ...
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0answers
49 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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1answer
375 views

Split a line feature using nearby points

I have a line shapefile and a point shapefile, and the line has its own segments and its attribute table, the point shapefile has points near the line above, not on it and the close ...
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1answer
68 views

How to analyse point data as covariate for areal data

I have two data sets: a) a set of polygons with areal data variables. b) point measures of various co-variates of interest (note I do not necessarily have a point for each polygon) How do I ...
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1answer
36 views

Create Random points

I have polygon with an attribute which has numbers populated in it. I would like to create random points for each of the polygon depending on the attribute. How could this be done ??
3
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2answers
517 views

Converting Vertices of Polylines and Polygons to Points and Maintain Attributes

I'm pretty sure someone has done this before, but I'm having no luck. I'm using ArcGIS Standard version 10.2.1 and I want to convert all the vertices of a polyline or polygon to points. Essentially, ...
0
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2answers
318 views

Find maximum and minimum value of points within a polygon buffer?

I have a series of 500m buffer zones along a polyline. I also have a series of points following the line, each point represents a 10m x 10m cell. I calculated the values of a field in each point known ...
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2answers
203 views

How can I group Points to make polygon via Python

I have an array of coordinates Point= [lat,long] ListPoint= [[38.203655,-76.113281],[38.10,-76.12],..] I wanna make a polygon that contains all these points ? There is a project developed by ...
2
votes
1answer
79 views

Using Python to create new point location based on various azimuth and distances

I have a feature class with thousands of points. In the same table with these point locations, I have two additional fields. One for azimuth, and one for a length (or distance) to move along that ...
0
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1answer
61 views

Associate points with polygon QGIS 2.2

I want to associate a point layer with a polygon layer so that I can do zonal statistics. In the image below, the polygon layer represents roughly the metro area of a certain city. The point ...
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0answers
52 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 ...
2
votes
1answer
84 views

Averaging XY points locations if in close proximity automatically over a large dataset in R

I have a point dataset (XYZ values) containing a few million points covering a 5km x 5km extent representing maxima locations. However there a great deal of these points which exist in 0.5m of others. ...
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1answer
69 views

Point-sampling rasters using R? [duplicate]

I need to be able to sample many raster files (imported from GeoTIFFs) using a previously defined set of spatial points, using R. What's the best way to do this?
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68 views

Pointstack with different count-1-symbols / SLD / GeoServer

I try to use the pointstack sld to visualize my data at different scales. I used the example from http://suite.opengeo.org/opengeo-docs/cartography/rt/pointstacker.html, and everything is fine. ...
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0answers
44 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 ...
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2answers
44 views

Creating Many Uneven Buffers

Qgis 2.2, Windows 7 I am looking to create buffers around city lights (the raster). Currently, I have simple polygon buffers around the point layer (oecdminusa), but this is not accurately capturing ...
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0answers
18 views

Point in Linefeature build through specific topology rules

i want to build Lines from Point Features following different topology rules (that lines aren't like randomly build, but how i should be following the extent from other polygons for example.. when ...
0
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1answer
139 views

Creating points based on coordinates in MapBasic

I am currently working on a MapBasic tool that generates start and end coordinates for a polyline layer. So far I have successfully populated 4 columns in a table (SX, EX, SY, EX) with coordinates of ...
4
votes
2answers
195 views

How to speed up a query for nearest linestring to point data

I have processed a Strahler stream order layer with a lot of river linestrings (type: Multilinestring) and their corresponding strahler number (see information here). Besides I have a point layer. I ...
3
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1answer
113 views

polygon from exterior points

How to convert points data to polygon, so as to form polygon from exterior point as shown above
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2answers
275 views

GeoServer create layer from PostGIS (data type point)

(Several days ago a user on gis stackexchange suggest that I should use OpenGeo (I was using geojson before). I succeed at what I was doing at that time, but now I have a different problem.) I was ...
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0answers
33 views

Multiple Centroids within a dataset based on distance

Is there a way that we can find out the centroids of clusters within a dataset while differentiating one cluster from other based on distance not on any attribute value. The dataset is present in ...
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0answers
31 views

Can't get X coordinate of PointM in PostGIS

Here are two queries, and I can't understand how to filter points if st_x does not work in WHERE clause. select st_x(geom_merk), st_asewkt(geom_merk) from road_density limit 5; ...
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2answers
143 views

QGIS 2.0 Automatic generation of a vector layer out of a point layer

I am an environmental engineer and the aim of my QGIS 2.0 project is to visualize the results of a sewage water system inspection. In a first step I included the hoppers from a csv file and added a ...
0
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1answer
51 views

Get all points with in some range of a point (or range of point)

I have got a list of points and a fixed range (10m). So what I have to do is for each point I have to find all the points present in a table with the 10m range of the given point. For example: Let ...
2
votes
1answer
58 views

Identify geographic location to points

I am quite new in QGIS and I really need your help. I have a map of Kenya divided into 68 districts and I have coordinates of 30.000 schools. The points have one variable besides the latitude and ...
1
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1answer
92 views

Adding XY coordinates from a point feature class to a one to many related table in ArcGIS 10.0

I have a point feature class with a one-to-many relate to a table. I would like to add the XY coordinates of each point in the feature class to the related table where the ID field matches. Of course, ...
0
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2answers
92 views

How to get information about only one data point?

I have a vector-point shapefile. The data are not dense (about 1 x 1 degree). Lets say that every point includes value of average wind speed. I would like to create a interactive web-map so that ...
1
vote
2answers
67 views

Finding routes in which more than one car passed (gps data)

I'm using ArcGIS 10.1. I have point GPS data of routes of several cars over a few days, and I want to find only the routes where more than one or two different cars passed through (Each GPS points ...
7
votes
1answer
258 views

How can I transform polylines into points every n metres in PostGIS?

Question in pretty much the same as this, but I need to use PostGIS. I have a number of polylines, and want to trasform them into points every n metres along these lines. edit: Thanks a lot to ...
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0answers
28 views

Creating a point layer from lat/long coordinates [duplicate]

I have a spreadsheet that lists the lat/long coordinates of several locations I wish to map. I would like to produce a geocoded point layer in QGIS. How do I do this? Thanks!
2
votes
1answer
511 views

Problem creating point shapefiles programmatically using python in QGIS 2.2

I am trying to create a point shapefile in the memory buffer (for a temporary label) and then zoom to the extents on this buffer. The working (in version 2.1) test code for this is: def ...
2
votes
1answer
82 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
3answers
314 views

Draw line between points from multiple datasets

I have 2 point datasets and want a tool or script to draw a line between all points in one dataset to all the points in the 2nd dataset. Is it possible? I have tried ESRI "Point Distance" and ...
3
votes
1answer
148 views

Select points approx. 2000 metres from another point along a river?

I have a series of points representing a river network (See Image Above). Each point contains attributes on Latitude, Longitude, Z value and Length calculated using flow accumulation. The river ...
3
votes
1answer
150 views

How to calculate distances between several points along network?

I have several points (bicycle share hubs), and I want to calculate the distance between each of them using a network. I want a CSV/XLS that has three headers: hub_id1, hub_id2, distance. I've ...
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2answers
158 views

How to get an indication of how points are spatially distributed?

Let's say I have a set of points and I want to get an indication of their spatial distribution. That is, if all points are at one location a possible return value would be 0, whereas if all points are ...