The direction and/or volume of something moving across a surface or within a network. Note this tag is primarily for data or function related questions as opposed to cartographic representation.

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28 views

Asset point IDs, pipeline and flow direction

I have a data set of a sewage pipe network and point data (assets). I would like to: first calculate the flow direction of pipes (polyline feature) assign IDs to the pipelines using asset IDs ...
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0answers
38 views

ArcGIS ArcMap average values in a single flowline

I am newbie in Arcmap. I need to get the average (Velocity) values of 1000 points on my long flowline. I tried to make parallel lines on each gridpoint using the "copy Parallel" function. But there ...
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1answer
38 views

Exporting massive gps tracks to a map

I have about 1000 vehicle equiped by a GPS sensor and 3G connection. Each vehicle feeds a csv file -using 3G connection- with its current location every 5 sec. Each vehicle have its own CSV file. ...
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1answer
73 views

How to extract drainage network through gdaldem

From gdaldem I can view slope, aspect, and hillshade maps. "gdaldem slope manj.tif ouoi.tif -p -s 60" "gdaldem aspect manj.tif gg.tif" "gdaldem hillshade manj.tif hh.tif" Is there any command to ...
5
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1answer
384 views

How to assign correct flow direction to stream network polylines?

I would like to create a map showing the results of watershed analysis as well as the resulting stream network with flow direction. I have a stream network which has been created from the flow ...
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1answer
66 views

How to create a barrier feature class to use in a geometric network?

I am working with the NHD and need to isolate stream segments upstream of barriers. I have too many barriers (thousands) to do this manually using the Geometric Network barrier tool on the toolbar. ...
2
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0answers
78 views

How to add flow arrows to groundwater table map?

After I had created groundwater table map, I tried using 3D Analyst>Steepest Path to add groundwater flow arrows to the map. However, it didn't work. Would you please let me know how can I add these ...
1
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1answer
54 views

When was MFD renamed to FD8?

According to my understanding, the Multiple Flow Direction (MFD) algorithm was originally defined in The Prediction of Hillslope Flow Paths for Distributed Hydrological Modelling using Digital Terrain ...
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1answer
283 views

Understanding percentage drop-raster (flow direction-tool)

I'm creating a Topographic Wetness Index using a python script (http://arcscripts.esri.com/details.asp?dbid=16750) As I don't want this just to be a blackbox, I'm trying to understand the different ...
2
votes
2answers
535 views

How to display arrows on pipes from upstream to downstream using QGIS?

I am trying to display arrows on pipes of a sewer network so their direction is from upstream to downstream edges of the pipes. I have managed to display those arrows on a polyline layer (which is ...
1
vote
1answer
512 views

Determine use of pipes in a geometric network

I am trying to understand how to use the Geometric Networks in ArcGis 10.1 For the purpose of my experiment, I built a simple network composed of a few connected pipes, one source (left triangle) and ...
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0answers
402 views

Arrow flow lines from a contour map

using QGIS (or even GRASS) is it possible to label a contour lines shape with arrows that indicate the flow direction? Briefly: I have a point shape with elevation values. I make an interpolation map ...
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2answers
354 views

R packages for deriving spatial clusters from origin-destination matrix

I have a matrix of origin-destination flows and I am trying to figure out the best way to derive X number of functional spatial clusters from the data. I haven't done this particular type of analysis ...