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

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1answer
59 views

Correct Projection for calculating centroids of a group of points?

I have a long list of points covering all of North America for which I would like to calculate the centroid (by grouping points based on the "Name" column). My approach is to take the WGS84 co-...
4
votes
2answers
185 views

Oil and gas well symbology for geoserver

I need to symbolise an oil and gas well dataset in geoserver. I have the dataset symbolised in ArcMap using the standard esri well symbols. Is there an easy way to convert this esri layer file into ...
0
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2answers
46 views

remove certain points from point shape file

I have a point shape files with 9674 points.The attribute column has three fields: X, Y and value. Out of these 9674 points, I want to remove 1700 points based on X and Y values (I know the X and Y of ...
6
votes
1answer
411 views

Is there a “Disperse Markers” tool for QGIS?

I am using ArcGIS, but either I would like to use QGIS and maybe want to switch completely later. A have a point overlapping problem, as a result of geocoding of addresses. I have not found any ...
2
votes
1answer
472 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
2answers
3k views

How to create a graphic point by xy value?

I have implemented this code to create point event layer by xy text file, however I'm wondering how to create a point graphic by xy value? This script draws point graphic by mouse down. When I ...
5
votes
1answer
418 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
2answers
907 views

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

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 ...
1
vote
1answer
89 views

GeoDjango - save two Point fields, one for geography and one for geometry

Most of the explanations I've read for geography and geometry seem to suggest that one must only use either geometry or geography, and that the only way to use both is to cast/convert between one and ...
2
votes
1answer
63 views

How to create azimuth raster layer by pyqgis?

I want to create an azimuth raster layer base of single point shapefile, for this I write below code that create a memory point layer that each point in memory layer is center of each pixel and have a ...
7
votes
4answers
5k views

How to extract POINT from a [LINE|MULTILINE]STRING

I'd like to create a vectorLayer in QGIS to display all the points that form a LINESTRING or a MULTILINESTRING stored in a PostGIS DB. I think that I need to transform all points of LINESTRING (or ...
6
votes
2answers
167 views

How to speed up this script in QGIS?

I am a new in PyQGIS, I want to create a Point layer from a raster layer. In table of point layer created, there is 3 fields by name of "X_coord", "Y_coord" and "Azimuth", each point in Point layer ...
0
votes
1answer
56 views

Select by Location using first points of polyline

I am trying to select a point from a point layer that intersect a polyline layers firstpoint and using arcpy. I am getting an error "ExecuteError: ERROR 000622: Failed to execute (Select Layer By ...
3
votes
1answer
77 views

Adding hover pop-up notes to map Arcmap desktop 10.3

I have a layer of points defining a variety of geologic features overlying a global map. I would like the user to be able to hover over a point and see a description of that feature. Hyperlinks ...
1
vote
1answer
177 views

Error when trying to plot legend for geom_point with ggplot2

Here's some mock code to go along with my problem: #read in libraries library(ggmap) library(sp) library(raster) library(ggplot2) #read in country shapefile, project, fortify for mapping with ...
2
votes
0answers
131 views

“Geometry cannot have Z values” exception in ArcGIS Engine

I'm trying to put a list of point features (selected points) into a new FeatureClass. but when I add them to my FeatureClass I get the "Geometry cannot have Z values." exception on the line "buff....
2
votes
4answers
2k views

Finding center point of MULTILINESTRING using PostGIS?

How to find the center point of MULTILINESTRING, which lies on the multiline? I am using SQL in PostGIS
0
votes
1answer
462 views

Try to load GeoJSON object with OpenLayers 3

I'm a bit new to working with OpenLayers 3. I'm trying to load a GeoJSON object in OpenLayers 3 but it display the center only point[0,0], which not even in my GeoJSON object, where I'm going wrong. ...
1
vote
1answer
28 views

inserting value from raster into overlaying point field

I am using ArcGIS 10.3 for Desktop. I am using an etopo bathymetry map and would like to determine the depth of ~50k points in another layer. I am sure there is a simple tool for this but I am ...
0
votes
1answer
61 views

Changing default point symbol?

I am trying to change the default point layer symbol to a set one. For example I have a fire hydrant point layer that is represented by a default point symbol when I import it into my map. Is there ...
0
votes
0answers
3 views

Retaining Raster Point Data Using wms [duplicate]

I have a single band raster being served via geoserver wms. When I view the raster through geoservers built in openlayers viewer I get different point value results than if I ask geoserver for a ...
1
vote
1answer
101 views

Finding and merging lines that touch in PostGIS?

I would like to select and merge segments that touch like in the image below. My table contains single segments with their own id (shown in the figure), I just want to isolate single "group" of ...
3
votes
1answer
76 views

Is it possible to create points that represent lines in QGIS 2.8.Wien?

I want to create points to represent lines from a line layer. This is similar to creating points to represent polygons. Does anyone have an idea on any useful plugin or the best way to do this?
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0answers
16 views

How do I generate a sampling path by numbering points?

I need to number points from left to right and then the next row of points the numbering must continue from right to left, then again from left to right the row thereafter - and so on, and so on. ...
2
votes
2answers
91 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 ...
3
votes
1answer
103 views

Rotate symbols perpendicular to line angle (QGIS)

I have lines representing curving streams and want to angle symbols at various points on the streams so that they are perpendicular to the angle in their particular locations. What QGIS seems to do ...
2
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0answers
28 views

Adding attribute data together within multiple polygons in QGIS? [duplicate]

In QGIS I have two vector layers, the first is a set of polygons and the second is a series of points. Each point has a numerical attribute associated with it and is located within one of the ...
2
votes
1answer
152 views

Selecting features of vector layers based on another vector layer using QGIS?

I am using QGIS 2.12.2. I am using three vector layers (point, polyline and polygon shapefiles) of the region of interest. Any advice in making the selections from one dataset based on the other ...
0
votes
2answers
110 views

Point feature plots in wrong place in QGIS?

I am using QGIS 2.12 on Mac OS X Yosemite 10.10.5. I have a single point with given latitude and longitude. I want to create a new vector layer (shapefile) which will plot one point on the map ...
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vote
2answers
652 views

Distance between points along polyline ArcGIS for Desktop?

I'm using ArcGIS 10.3 (Desktop), and I'm trying to measure the distance between points following a path determined by a set of polylines. Hand measurement is not a viable option-- there are ~7500 ...
1
vote
2answers
271 views

Points on Map overlapping/covering city and town names

I have a map with many points, these points map incidences of landmine accidents in Colombia. There are thousands of points and cover up parts of city and town names, in some cases the entire lables ...
4
votes
1answer
54 views

Is it possible to locate a specific marker point on a raster using python and use that location for georeferencing

I have several scans of the same map, which I would like to georeference. I can not use arcpy.WarpFromFile_management(...) as the rasters are slightly different due to scanning. Is there a ...
0
votes
1answer
46 views

Connecting two points in ArcGIS for Desktop?

I have two types of point shapefiles. These two points are linked with another attribute table. Each Point from column A is linked to single/multiple values in column B. Each of these object_IDs have ...
2
votes
1answer
134 views

Trouble adding proportional circles on top of symbolized polygon in ggplot2 map

Data: Zipped ea.ml1 shapefile can be found here, and the country outline can be downloaded here at the GADM site. I've been using the Ethiopia ESRI shapefile. Branch locations are here. Per the ...
2
votes
0answers
39 views

Create polygon layer from point data with number attribute where polygon encloses n% of point data attribute value in QGIS [closed]

I have two sets of data, one is the CodePoint Open with the location of all of the uk postcodes, the second is from online form data from which I've extracted the postcode and telephone area code, and ...
1
vote
1answer
68 views

Connect multiple 2 points with a line in ArcGIS?

I have a table in which each row has two columns representing the objectID of two different point features in the Map. There are thousands of such rows. How do I connect the each of these two points ...
8
votes
1answer
74 views

How can I export a list of points as a matrix in ArcGIS 10.0?

I have a grid made of points (see attachment) with values for altitude extracted from a DEM. I need to export these values not as list, but as a matrix of size 50x50 to be read in SciLab. The grid is ...
4
votes
2answers
133 views

Add a point on a spplot in R

I have to add a point on a existing spplot in R. I need it only for a visual purpose. I have the coordinates of the point, but I don't know how to change the code in order to add the point. This is ...
6
votes
2answers
925 views

How to create zip code areas from point data?

I have a point dataset which has zipcodes for a certain region. This zipcodes have been marked on the basis of lat long collected. So each zipcode is repeated as it would be useful to show the region ...
1
vote
1answer
95 views

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

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 ...
3
votes
2answers
427 views

gDistance to determine closest point to polygon: does changing projection change results qualitatively?

I'm using gDistance from the rgeos package for R to find the nearest point to a polygon. The projection of both points and the polygon is +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,...
0
votes
0answers
243 views

PyQgis: How can I preserve order or index when adding features to a Vector Layer from a file?

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 ...
2
votes
1answer
63 views

Complex polyline traversing with searchcursor

I have a very specific question about searchcursor traversing complex polyline. My setup is: I imported public transport routes as a single polyline with length in meters. Along this polyline I want ...
0
votes
1answer
37 views

Snapping point to point nearest to it in ArcGIS for Desktop?

I am using ArcGIS 10.3 for Desktop. I have 2 point features centroid and station. I want to snap all the points of centroid to the nearest point in station such that centroid is only snapped with ...
3
votes
3answers
484 views

How do I plot points as graduated/proportional circles in R?

I'm back again with more R mapping questions! This one is concerning symbolizing points by a certain attribute with graduated/proportional circles. DATA: My full code can be found here if you're ...
10
votes
4answers
9k views

Get all the points of a polyline

I have some polyline feature objects in python. Now I want to get all the points of polylines. For example, if a polyline has start point [0,0] end point [5,5]. Result: [1,1];[2,2];[3,3];[4,4];[5,5]...
4
votes
1answer
56 views

PostGIS point distance from polygon not 0 when on edge

I have a pretty simple problem: SELECT * FROM ST_Distance(ST_GeographyFromText('POLYGON((70 -40,70 -39,71 -39,71 -40,70 -40))'), ST_GeographyFromText('POINT(70.48 -39)'), False) returns 118....
9
votes
1answer
237 views

Point sampling along a pole-wrapping coastline with PostGIS

I am working on a task that requires me to get sample points every 1000 km along coastlines, and have run into a problem with Antarctica. From what I can tell, it seems to be an issue with the use of ...
3
votes
2answers
81 views

Select point(s) from given coordinate and move to new coordinate using arcpy

Goal: Move address points to their correct location. Plan: I have a layer of AddressPoints of which some need moved to a new location. I want to take a line layer (called ...
2
votes
2answers
3k views

Layers with same coordinates not lining up

I have a project where I have a few layers (State of Texas, cities, roads, etc.). They are all resaved and projected to NAD83 / UTM zone 14N EPSG: 26914. The project CRS is also NAD83 / UTM zone 14N ...