Stack Overflow
Stack Overflow

Questions tagged [gis]

A Geographic Information System (GIS) captures, stores, analyzes, manages, and presents data that are linked to location(s). The GIS Stack Exchange should be considered for questions with this tag.

According to Wikipedia:

A geographic information system (GIS), geographical information system, or geospatial information system is any system that captures, stores, analyzes, manages, and presents data that are linked to location(s). In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology.

There is a Stack Exchange site devoted to Geographic Information Systems.

6555 questions
11
votes
2 answers

D3js: How to design topographic maps?

Given a GIS raster with elevation data, How to design a topographic map in D3js ? Is there any example of relief / topographic maps of cropped lands made using D3js ? Not working: I explored the posibility of .tif > gdal_contour.py > .shp >…
Hugolpz
  • 17,296
  • 26
  • 100
  • 187
11
votes
1 answer

rgdal / readOGR - unable to read shapefile from .zip

I'm trying to load a zip level shapefile to do some plotting, per: https://github.com/hadley/ggplot2/wiki/plotting-polygon-shapefiles http://www.nceas.ucsb.edu/scicomp/usecases/ReadWriteESRIShapeFiles etc My…
alexwhitworth
  • 4,839
  • 5
  • 32
  • 59
11
votes
2 answers

How to use GDAL to create geotiff from tiff and 4 corners latitude and longitude

I have an image (map) without geo data in TIFF format. I need to get GeoTIFF file from my image. I have latitude and longitude for each corner of my map. How can I add my geo data to my image in Google spatial refence to get geotiff? I know that…
rowwingman
  • 5,589
  • 7
  • 33
  • 50
11
votes
2 answers

plot multiple shp file on a graph using spplot in R

I have 3 shp files representing the house, room, and beds of a house respectively. I need to plot them on a graph using R so that they all overlap with each other. I know that in plot function, I can use line to plot new lines on top of the existing…
lokheart
  • 23,743
  • 39
  • 98
  • 169
10
votes
7 answers

Join multiple line segments into one line - GIS

I have a map that I have digitised and converted to a vector layer (the rivers only). The problem is that the vectorisation has produced a large number of segments for each river, that show up as different features (each may have multiple straight…
LittleFish
  • 789
  • 3
  • 10
  • 15
10
votes
4 answers

Quicker way to calculate geographic distance between two points

I borrowed the following method from somewhere on the internet (Can't remember where). But its doing a straight forward process, finding the distance between two gps points. It works just fine, except that it may be a little slow, as I'm running it…
Steve
  • 21,163
  • 21
  • 69
  • 92
10
votes
2 answers

How to get a list of every Point inside a MultiPolygon using Shapely

I have the following MultiPolygon: MULTIPOLYGON ( ( (10.8849956 49.8901705, 10.8849507 49.8902499, 10.884969 49.8902588, 10.8851033 49.8903298, 10.8851183 49.8903132, 10.88512882654868 49.8903054, 10.8851246 49.8903054, 10.8851246 49.8902754,…
Thurse
  • 253
  • 1
  • 3
  • 16
10
votes
2 answers

How to use geopanda or shapely to find nearest point in same geodataframe

I have a geodataframe showing ~25 locations represented as point geometry. I am trying to come up with a script that goes through each point, identifies the nearest location and returns the name of the nearest location and the distance. I can easily…
rzt101
  • 127
  • 1
  • 1
  • 6
10
votes
2 answers

GDAL : Reprojecting netCDF file

I am trying to convert netCDF files to EPSG:3857 for use with Mapbox by using GDAL. This would be .nc to .nc conversion. Not to raster. I am open to using GDAL or other methods to do this. This data must be reprojected before it goes to a console…
David
  • 605
  • 2
  • 14
  • 44
10
votes
1 answer

Importing raster data into NetLogo results in a column with all patch variables = 0

When I use this code to import a raster layer into NetLogo and resize the world, all patch variables of the last column is zero when it should contain data. This happens only for a few rasters from the same landscape. set rasterLayer…
Anisha Jayadevan
  • 185
  • 12
10
votes
6 answers

Order by nearest - PostGIS, GeoRuby, spatial_adapter

I'm trying to do an order query that finds records nearest to the current_user. I know the distance between the two points is: current_location.euclidean_distance(@record.position) How can I work this into a PostGIS (or…
DanS
  • 17,550
  • 9
  • 53
  • 47
10
votes
2 answers

Comparing/Clustering Trajectories (GPS data of (x,y) points) and Mining the data

I've got 2 questions on analyzing a GPS dataset. 1) Extracting trajectories I have a huge database of recorded GPS coordinates of the form (latitude, longitude, date-time). According to date-time values of consecutive records, I'm trying to extract…
Murat Derya Özen
  • 2,154
  • 8
  • 31
  • 44
10
votes
2 answers

What SRID should I use for my application and how?

I'm using PostgreSQL with PostGIS. All my data has already decimal lat/long attached to it (i.e. -87.34554 33.12321) but to use PostGIS I need to convert it to a certain type of SRID. The majority of my queries are looking for data inside a certain…
avatar
  • 12,087
  • 17
  • 66
  • 82
10
votes
1 answer

Change colors of raster plot in ggplot2

I am trying to make a raster plot using ggplot2 rather than the raster package plot function for some irrelevant reasons. I would like to scale the colors so that the minimum temperature on the plot is blue and the maximum temperature on the plot is…
vitale232
  • 615
  • 1
  • 11
  • 21
10
votes
1 answer

GDAL - gdalbuildvrt "tif file not recognized as a supported file format"

I am trying to create a virtual raster (VRT file), that joins a large amount of GeoTIFF rasters. I am using gdalbuildvrt command in a Windows 7 environment. Below is the syntax used. gdalbuildvrt -input_file_list C:\listing.txt -srcnodata 0…
jhc
  • 1,739
  • 3
  • 21
  • 46
1 2 3
…
99 100