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1500 questions
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4 answers

Free GIS software for orthorectification?

Could someone recommend a free and/or open source GIS application that can orthorectify map images?
Drew
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How to store lines and polygons in JSON documents?

Looking at the increasing NoSQL movement and considering that databases like MongoDB offers a new perspective in flexible data storage for GIS. What is the best way to store lines and polygons in JSON documents to take advantage of 2d indexes and…
Pablo
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File size inflation normal with gdalwarp?

After using gdalwarp to project and align-to-grid (via -tap) a number of rasters I noticed that the output rasters were significantly larger than the original rasters. A fairly thorough web search turned up this Trac issue: Frank Warmerdam…
Arthur
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6 answers

Open access repository of general GIS spatial data?

As a newcomer to using GIS for research, I am wondering if there are online repositories for spatial data, similar to package repositories for Linux distributions. For instance, I would be able to find things like "bathymetric map of the world's…
hpy
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4 answers

Triggering click event on Leaflet map?

Is it possible to make a click event occur at a particular lat/lon on a leaflet map? I would like to make a popup appear that is associated with a point at a particular location. I have tried several combinations of map.fireEvent('click', latLon)…
djq
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24
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2 answers

How to Import ESRI Geodatabase format .gdb into PostGIS

I ran into a problem when loading a ESRI Geodatabase format .gdb into PostGIS. I have data 2.5GB GDB file. I followed some tutorials on the internet, but it seems that doesn't work out. I created a database "SampleNY" I executed this from the…
user3001937
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24
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8 answers

What are people using LANDSAT data for?

Obviously it's potentially a very powerful tool, but I'm curious as to what practical applications people are using it for? Admittedly, this is a very broad question... The reason I ask is because while I personally am aware of a number of…
Jacques Tardie
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24
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1 answer

Zoom further in than level 19 with leaflet javascript API?

We're using the leaflet JavaScript API with a tile layer which supports zoom level up to 19. I'd like users to be able to zoom further even if the tiles blur as they have to place markers to a high degree of accuracy. Is this possible ? We want…
ajayel
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24
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5 answers

Using replace string function in QGIS Field Calculator

Within an attribute table, I'm trying to replace one string with another using the replace function. As an example, there are a number of features whose field "NAME" contains the string '(B)' and I'm wanting to replace this with the word 'County'.…
GrahamD
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24
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9 answers

Viewing LiDAR data from web browser?

I am looking to host lidar data on my own server and give clients the ability to view that data through a web browser as a 3D point cloud (file would be in .las format or equivalent), possibly with the ability to measure features. Does anyone know…
jtgis
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24
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4 answers

Changing projection of shapefile in QGIS

How do I change the projection of my shapefile using QGIS? The default projection is set to EPSG:3003, I want to change it to WGS84 EPSG:32632. When I do a reprojection or I change projection in the properties mask I don't have the correct…
Filippo
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24
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2 answers

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: Furthermore, I would like to avoid using a point that is on…
fmark
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3 answers

What do these curly graphics represent on this map?

What do the two curly graphics to the left and right of this map represent? They are the only two on the map and seem to be attached to the border of an area. I'm sorry I haven't posted the full map, I'm not sure I'm allowed.
Jake
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2 answers

Add/Remove legend with Leaflet layers control?

I have two overlays http://02d0c8c.netsolhost.com/dev/lcb_census_layers3.html that can be turned on and off with a Layer Control. I’d like the legend for each layer to turn on/off along with the layers. I am new to JavaScript and new to Leaflet.…
ryan
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24
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2 answers

PostGIS Geometry Query returns "Error: Operation on mixed SRID geometries" only for certain values

I have PostGIS table with two geometry columns, both defined with SRID 4326. I can insert into the table without problem, using the following INSERT statement (where lng and lat are values passed in programmatically): INSERT INTO pad_meta ( …
jessykate
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