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

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6
votes
3answers
89 views

Waypoints with coordinates in R

I have a SpatialLineDataFrame with 20 observations of 4 variables (in WGS84). I want to create waypoints every 10 meters. Every waypoint will has the x y coordinates. I tried to do it manually like: ...
2
votes
1answer
881 views

What are nodes in ArcGIS and how do you create them?

I want to create a elevation profile of a cross section so a polyline on ArcGIS. I wanted to regularly space around 1000 points per 1700m long xsection and extract elevation data for each node/point ...
1
vote
1answer
16 views

Getting NULL-values when point sampling USGS (SRTM 1 Arc-Second Global) grid (QGIS 2.8.2)

I use the Point Sampling Tool in QGIS to transfer gridvalues (of DEMs) to point features. This goes well with grids from f.i. MapMart (SRTMHARRIS_DEM), but I get only NULL-values when using grids from ...
3
votes
1answer
171 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 ...
0
votes
0answers
15 views

Issue when creating points with php and entering them in postgis

I pass some data to a postgis table defined as: CREATE TABLE categoriesdata (id serial NOT NULL, name character varying(200), geom geometry(Point,4326), CONSTRAINT obj_geom_pkey PRIMARY KEY ...
1
vote
1answer
30 views

What is CID field created by Create Random points?

In ArcGIS the result of Create Random Points tool when using a feature class to constrain the extents has an attribute called CID. What do the values in this field represent?
1
vote
1answer
254 views

How to generate random points with minimum distances between points in multiple polygons

I am looking to create random points for a random stratified survey. There are three different categories being surveyed; for each, I have a single shapefile, each containing a number of polygons. I ...
3
votes
4answers
8k views

Change number of decimal digits for features in ArcGIS 10?

I am editing vertices in polygons and points in ArcMap 10, and realised that they only hold 3 decimal digits for the X, Y coordinates, but I would like at least 6 decimal digits. Even if I type in ...
1
vote
0answers
17 views

Display different symbols in QGIS using Point Displacement renderer

How to display different symbols (not different in size, different in shape and color) on the same point in QGIS 2.8 using Point Displacement renderer? I want my layout with symbols around the ...
0
votes
1answer
47 views

Clicking on points in ArcGIS Android

This seems like it should be very easy to do, but I am unable to click on a point and have the map recognize that I have clicked on the point. I first tried just creating a simple point, setting the ...
2
votes
3answers
551 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 ...
2
votes
0answers
34 views

Generate ID for the grid of points from top-left corner down

I have a grid of points extracted from a raster. I need to give them a new ID value to be able to join values from it to another grid in rotated system of coordinates.The automatically generated ID ...
5
votes
1answer
327 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 ...
7
votes
4answers
2k views

How to create different diameter circles round points?

I want to map a tree survey. I am thinking that I will plot positional points of the trees and then add other data like tree type etc. to the attribute table later. Is there a way I can have an ...
0
votes
0answers
29 views

Using XY tool in ArcGIS to create points, how do I export them? [closed]

we are creating coordinate points in ArcGIS using an Xytool. these points do not exsit as a layer or file, how can we extract these point into a file or layer?
2
votes
1answer
398 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 ...
3
votes
1answer
68 views

Space time analysis. Finding spatial patterns (cluster&disperse) over time in point data sets

I am trying to describe/find statistically spatial patterns in a point data set of industrial sites. The points feature apart from their location, a date for their opening, a date for their closure ...
3
votes
3answers
118 views

How to calculate path length of each point from the start using arcpy?

As shown in the picture below I would like to calculate the path length of each point from the start. Can anyone give me some help in writing this in python for ArcGIS?
0
votes
2answers
264 views

How to extend polylines to the nearest point

Hi could anyone tell me a way of getting my polylines to search for a point within a certain number of meters of their start/end points and extend to it? edit: There was some broblem uploading a ...
1
vote
3answers
641 views

Divide Line Into Sections Using Points Offset from It in ArcGIS Desktop?

I have track (line) and milemarkers (point). Each point is offset by a different distance. Is there a way to find where each point would intersect the line if going perpendicularly out from the line? ...
1
vote
1answer
71 views

How can I assign attribute IDs to points in an 85000 point spread according to a grid scheme?

I am working on a pretty complicated grid system and cannot figure out a way to name each of the points in my shapefile. The X of the grid originally started with A and ended with AX. We have ...
1
vote
1answer
25 views

Adding point layer in QGIS from SQL Server failing

I just downloaded QGIS a few days ago (version 2.8.2-Wien) but I am not able to get it to work as I thought it would. I tried pulling in spatial data from sql server (a "geometry" column containing ...
1
vote
1answer
23 views

How to create a Planer Point Pattern in R using a Shapefile of point features

I have just started to learn spatial analysis of point pattern with R. On page 20 of this book, the "Swedishpines" dataset has been used for inspection purposes. However, I want to use my own dataset ...
1
vote
1answer
45 views

How to adjust a complete shapefile of multiple points on ArcMap taking other few as reference?

I recieved a shapefile with georeferenced trees, but they didn't used a GPS to get the coordinates (not sure how they did it, some traditional stuff maybe?). So, the position doesn't match exactly on ...
1
vote
1answer
54 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 ...
3
votes
1answer
50 views

Spatial sampling design

I have some plots of land spread across the landscape. Sometimes a parcel is subdivided in different sectors. For each parcel (and, in case of subdivision, for each sub-section) the quality of ...
1
vote
1answer
45 views

Country border between two points

I am trying to extract country borders between two points, using Python. The border is a Shapely Polygon.exterior or LinearRing, the start and end points are Shapely Points. My idea is the following: ...
1
vote
0answers
25 views

Splitting up a single polygon into many polygons of equal point count

I have point data split into 15 different values and want to split up the (green) polygon into a number of smaller polygons each containing the same number of points so that I can make a chloropleth ...
0
votes
4answers
70 views

How to Remove Multiple Labels for Stacked Points? ArcGIS 10.2.2?

I have a point feature class, in certain areas there are stacked points. These stacked points are accurate. However, when I label the points I am getting a label for each point, which is okay for each ...
0
votes
1answer
34 views

Associating 2 point files

In the image below, the green points are associated with radar wave amplitude data. They're generated from RasterToPoint, so they're at the centroid of each pixel and have only the value of the ...
2
votes
1answer
36 views

How to create a raster of equidistant points with distance in meters using QGIS?

I need a set of equidistant points (like a raster) each in a 1km distance to the next over a certain area, in my case Germany. I know the feature "regular points" in QGIS where I can do just that but ...
21
votes
5answers
29k views

Get list of coordinates for points in a layer?

I've got a layer in QGIS that is comprised of points. Its attribute table doesn't have (show) the corresponding x and y coordinates for each point. Is there a way for me to extract a list of ...
0
votes
2answers
46 views

Create a circle polygon in GMaps.Net?

I found this function and converted it to VB.Net. It draws an oval rather than a circle. What do I need to do to fix the calculations? Dim seg As Double = Math.PI * 2 / segments For i As Integer ...
2
votes
0answers
35 views

Interpreting results of QGIS intepolation and Heat map from point shapefile

I have taken a step interpolation and heat map of the data point shapefile (building Centroid) with QGIS ver-2.8.1, as shown below. My question are: What is the difference of the two methods? How ...
1
vote
1answer
50 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 ...
1
vote
1answer
21 views

How to create a rule-based gradient using an expression

I am mapping points with values from 0-100 and want to display these using a gradient color scheme. However I also want to specify the breaks as regular intervals along this range. For a gradient QGIS ...
0
votes
0answers
29 views

Points nearest to polygon: nearest to edge of polygon or centroid?

When using ArcGIS and performing a Spatial Join of points to polygons, there is an option to choose the closest point. Is the point that is chosen closest to the edge of the polygon or to the centroid ...
1
vote
0answers
51 views

Point to raster: QGIS vs ArcMap

I have an equidistant point grid (0.5m) and created a raster from it in QGIS and ArcMap, with different results: QGIS: Raster -> Conversion -> Rasterize Result: raster, with points in the top left ...
0
votes
1answer
70 views

How do I measure the distance between two points within a country arcmap

I have two shapefiles with points distributed over the whole world. I would like to measure the distance (like the crow flies in km) from each point in shapefile 1 to the closest point from shapefile ...
3
votes
1answer
6k views

How to add points to a point vector layer - QGIS

I have a point layer with multiple data points in QGIS, but I want to add some extra data points to it and adjust some info that we missed because the ground was wet and we needed to go around it. I ...
0
votes
2answers
33 views

Create point on a line with given distance from end in PostGIS

Does anyone know how to create points along a line (MultiLineString geometry) with a given distance in PostGIS? I'd like to create points at a regular distance over a line, which represents a ...
-1
votes
1answer
19 views

Converting start/end easting/northings to a single point for visualisation

I have eastings and northings for the start and end of 5m sections of the UK railway network. I want to convert these points to a central point between the start and end so I can visualise the ...
0
votes
0answers
30 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 ...
2
votes
1answer
571 views

Postgresql view with Point geometry returns QGIS error “(the_geom) sql = is an invalid layer and cannot be loaded”

I want to create a Postgresql view using point data. When I create the view, the geometry_columns table updates appropriately. Attempting to load in QGIS produces the error “(the_geom) sql = is an ...
4
votes
3answers
792 views

How to join number of point features into attribute of nearest line segment using ArcGIS Desktop?

I have point shapefile with lot of attributes, that represent road accidents and line shapefile with highways. What i want is to join attribute into line shapefile with value, that represent number of ...
0
votes
0answers
36 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 ...
0
votes
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 ...
1
vote
0answers
48 views

Loading lots of points on leaflet through time slider.

I'm trying to add more than 13 thousand point using Time Slider plugin, but as you can imagine the loading process of all these points puts a heavy burden on the map. Even the slider start to get ...
3
votes
1answer
75 views

Using arcpy to find geometry within another feature

In Arcpy, I would like to start with a point and then using its geometry method to find out if it is inside my polygon feature (Urban Areas) deeper than the buffer distance. This is a follow up to ...
0
votes
2answers
81 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 ...