Least Cost Path Tutorial with ArcGIS 10

hi my name is Luis barragán and I'll be talking to you about how to create a least cost path route using our GIS 10 you can follow me at twitter at lewis serrocold on my blog is technolon tobira blog spot.com now let's start seeing what we're going to do today now the requirements for this tutorial you're going to be needing our GIS tent with our character though I'm pretty sure you can do it with our view you're going to need the spatial analyst extension it must be activated in order to run the the tutorial now what we're going to analyze today the problem is we want to find an alternate route to build a road between origin which is in a town called Serra pelada and the destination which is in the tank or to mucosal the criteria we're going to use as a slope we're going to consider that higher slopes are more costly than lower slopes and we're going to use land use we're going to consider intervened land users more less costly than intervene areas for example farmlands will be less costly than forests well now what we're going to do is we're going to open our map document name of our map document is least underscore cost path tutorial now let's see what we have inside in this this MXT we have the origin points which is doing a little time to show origin point which is this black circle here on set oval of the our destination which is here to mucosal we also have the towns we have the rivers we have now are activated we have the streets we have the district of some physics which is this kind of pink border line we have the districts which are in yellow or study area we have the land-use we are here we do not have activated on our DM and the first thing we're going to do is going to create a tool box in order to to have our mouths separate from from the other toolboxes now we're going to say add tool box we're going to create a new tool box we're going to call it underscore please cost based on the square petracles give it an enter and select it and we're going to open it now next thing we're going to do is wonder we're going to add I'm sorry we will now add a new model we're going to enter here into model properties I'm going to change the name on the label we're going to call it least-cost bright this thing cannot contain blank spaces and you're going to put the label don't call it or at least wow now next thing we're going to do is going to check that the environment variables are set to the values we want we're going to make sure that the workspace is properly is properly set we also want to check the process extent and we also may check the raster analysis now I'm going to click here to see the values we currently have for workspace we want to check that it's pointing current workspace it's pointy to sign Felix gdv and our scratch work space is scratch on this course and Felix gdb our processing extent we want it to be snapped to our DM which is a 90 meter resolution or DM and our we want to make sure that our raster analysis the cell size is set to 90 which is the size of the DM data and we're going to set here - ok and to apply now as soon as would we saved them all will see that the name changes here now we're going to start adding the models that the tools that we're going to require for this model presumably the doors we're going to calculate the slope for that we go here to surface we select slope and we drag and drop it into the into the model we double click on slope and we're going to select as our input rester raster the TM now we check that it's the output is in our scratch work space we're going to keep degrees and we're going to keep the C factor as one and to apply next I'm gonna do is going to rename this to something you're meaningful we're going to type here the M slope now we're going to run the tool so when we reclassify our data we will have actual data to to reclassify we're going to select the recluse right tool and drop it here and a double click it all right we also let setup wizard in professor or diem slope there are classes value is value and we're going to classify it a little bit different we're going to select the quantile and we're going to select ten classes instead of five well click on OK and as you can see the old value is a range of old values the smaller they are the smaller the cost will be which is consistent with what we want we're going to apply here and okay we also want to rename this this output type here reclass slope the next thing we're going to do is we're going to get a weight overlay to go double-click on it and first thing we're going to do is we want to set the evaluation scale and a type here and from 1 to 10 in steps of 1 we need to apply now the next thing we're going to do is we now add our first input layer which would be our slope TM reclassify our class slope or input field is value and ok here as you can see our field values will match with our scale values which is pretty much what we want since we only have one the current influence is 100% now next thing we're going to do is going to add our land use and we're going to select this input category and we're going ok now we're going to start assigning values based on intervention we're going to do for farmland we're gonna line the three with shrubs two for subsistence farming we're going to use Street also for forests with intervention we're going to use eight mature forests use ten we want to keep that small just thank you as much as I'm going to protect our actual force the best way we can Arman growth we're going to use a nine for water ten because it's very expensive to build bridges wetland vegetations we're going to use eight and other users will use three and no data will keep on being no data now we're going to assign our weights we're going to give this one thirty four percent weight and we're going to assign to our slaw or 666 weight so you can see the warning disappeared because now it add up to 100 we're going to do apply okay and go to a little bit full extent and we're going to lay out to lay out and see what we have okay next thing we're going to do is when you rename this I'm going to name this costs now the next thing we're going to do is work on the estimate we're going to calculate the cost for moving from any sale to our destination and for that we're going to use the tool cost distance drag and drop right here I'm going to do a little bit of soon see a little bit better double click on cost distance and our input or feature source data will be our destination our input costs raster is going to be the cost we just got just calculate it we're going to leave black maximum distance so we'll use all all the data in the set now we want to calculate the back link which is the directions and we're just se-ho complying do okay now we're going to on a layout and pendulum here to see ya we're going to rename let's call this post distance and rename this hint next thing we're going to do is we'll calculate our East cost path using the outputs from cost distance with that we're going to use cost path dragon rub here and do a little bit of panning here and we will double click and cost round and we're going to select as our featured destination data we're going to select origin and select as destination field object ID since there's only one point is is that really important as input cost raster and select output cost distance or backlink we're going to do output act we're going to select called put back link now we're going to keep earth path type each cell in to apply ok we're doing Auto layer again and we're going to rename final output to least cost well now we run ready to run our mouths someone to full extent so we'll see how it works click over cause path and right click & melina tool and you can see as the different tools turn to red means they're processing the data now that it's finished we're going to close this we're going to right click on these cross paths I'm going to click on add to display so we can see our result close them all make sure that it's up here so we can see over here and here we can see your suggested and you're out from cerebellar Georgia mucosal and it's the screen tater that's pretty much it I hope you enjoyed this tutorial and that's all

Channel: Luis C. Berrocal

Views: 50,567

Rating: 4.9436622 out of 5

Keywords: ArcGIS, Spatial Analyst, Least Cost Path

Id: c3q0DpV8NQo

Length: 14min 50sec (890 seconds)

Published: Tue Mar 13 2012