An area of influence defined by boundaries related to distance. In human geography, this area is defined as the location from which customers or visitors are attracted. In hydrology, this area defines the location within watershed boundaries (also known as a drainage basin).

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Does Scimap work with QGIS?

Does anybody know if Scimap ( http://www.scimap.org.uk ) works with QGIS? I know it is supposed to operate with ArcGIS and SAGA but as I am very much a beginner with QGIS I would like to know if its ...
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51 views

Multiple watershed delination with QGIS

I am trying to divide a DTM model in subbasins but I have set specific outlet points for the subbasins, and not to use a thershold. Is there a tool similar to r.water.outlet but with multiple outlet ...
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Comparing areas of two raster files

I need to compare the areas of two rasters for calculating the percentage parts from another. For example, I have one raster file which shows separated agriculture fields. The value of each field is 1 ...
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64 views

Can 2 GIS layers which representing the same area be compared directly while having the same datum but different coordinate system?

My question is about how coordinate systems affect comparison of different layers - I have tried to refresh my memory about coordinate systems in GIS, but am still unsure about this situation. I am ...
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Calculate how to cover an area by recepetion tovwers

I am working in a Nature Reserve and we are putting up towers that will be used to to track certain animal with collars on. The towers work on line of site only. We must place the towers in a matter ...
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111 views

Catchment area calculation

I have a conundrum. I am trying to shortlist optimal physical locations in my county for developing recycling centres that serve the population. I have a vector point layer of the centre point of ...
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211 views

QGIS 2.0 Catchment areas by using a 1 hour walking time

i would like to have catchment areas around my points which show the area of an one hour walk. I looked around and found information about using the hiking funktion for calculating a distance with the ...
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33 views

Setting up a simple catchment area for shops using QGIS?

I would love to set up a catchment area around simple dots on a network map. The catchment should be separated by different range-areas (50, 100, 200m), just like isochrones. I tried the GRASS plugin ...
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41 views

Query processing time for network table creation using pgRouting 1.05

I am trying to follow these steps for creation of a network table using pgRouting 1.05. In my case I have two road geometry tables, one is bangalore_road and the other is all_india_roads. Obviously ...
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340 views

How to calculate Gradient from DEM?

I have a digital elevation model for a catchment area and I would like to calculate the gradient by cells. Is that possible and does anybody know the steps?