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20

I've been exploring SciPy's signal.convolve approach (based on this cookbook), and am having some really nice success with the following snippet: from scipy import exp, mgrid, signal, row_stack, column_stack, tile def gaussian_blur(in_array, size): # expand in_array to fit edge of kernel, by repeating edge values ny, nx = in_array.shape ary = ...


12

Gaussian blur is just a weighted focal mean. You can recreate it to high accuracy with a sequence of short-distance circular neighborhood (unweighted) means: this is an application of the Central Limit Theorem. You have a lot of choices. "Filter" is too limited--it's only for 3 x 3 neighborhoods--so don't bother with it. The best option for large DEMs is ...


12

In ArcGIS Desktop 9.3.1 and prior, right-click on the tool in ArcToolbox and select Edit Documentation. At version 10 it is a little bit different, this thread on Esri Support describes the issue: http://forums.arcgis.com/threads/405-Beta-10-ArcToolbox-Documentation Specifically, at 10.0, you need to access the toolbox item from the ArcCatalog window within ...


12

Because even the Microsoft code is buggy, it may be useful to provide correct pseudocode for the conversion. To convert decimal degrees x to degrees (d), minutes(m), and (decimal) seconds (s), do the following: Declare d, m as integer, s as float If x < 0, then sign = -1 else sign = +1 Let y = Abs(x) ' Work with positive values only. Let d = ...


10

One way to handle intermediate data is to use the in_memory workspace. For example: arcpy.Project_management(Footprints, "in_memory", out_coordinate_system) You can specify multiple in_memory objects by adding a name and path separator: "in_memory\temp1" "in_memory\temp2" ... If your datasets are very large and you are worried about cumulative ...


8

To revert to the ArcGIS 9 editing environment: "The setting is found in the Advanced ArcMap Settings utility, located in the \Utilities directory where you installed ArcGIS." From http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Reverting_to_the_ArcGIS_9_editing_environment/001t00000013000000/


8

Portable Python http://www.portablepython.com/ Interesting project you have will it be available to the GIS community? Maybe of interest Portable GIS http://www.archaeogeek.com/blog/portable-gis/


8

I'm not 100% clear on the effect you're looking for but... there is a geoprocessing tool called "Create Fish Net" that lets you create a grid of lines, and points, then you could use your polygons to clip the points. For "irregular" you can use the "Create Random Points" which creates N points inside a polygon and you can specify a minimum distance between ...


8

As far as I am aware there is currently no way to make schema edits in a geodatabase without either dropping and adding fields, or deleting and reloading feature classes/tables. The latter is what I recommend in order to maintain field order. What I normally do is: Make a backup of the original feature class Export the original feature class's schema to ...


7

I like Esri's ArcGIS API for Microsoft Silverlight/WPF, and also the ArcGIS Viewer for Silverlight. You can use Bing with these, or base maps from ArcGIS.com. Also, consider using SQL Server 2008 with Sql Server Management studio to prototype spatial sql queries. Isaac Kunen's blog is a good resource. Best when used with the Sql Server Spatial Tools from ...


6

I think you have to rely on your file system for this information. I've used openfiles from the command prompt to get this information from window file shares. You would need admin access to the actual server, so this might not be an option for you. C:\WINDOWS\system32>openfiles INFO: The system global flag 'maintain objects list' needs to be enabled ...


6

Within an Excel VBA macro, the following calls a Python script called test.py: Sub test() rsp = Shell(Environ$("COMSPEC") & " /c C:/test.py", vbNormalFocus) End Sub (Original source here) I've forgotten how to run an ArcGIS VBA module, but perhaps a similar line would work to call your python script. Another strategy that might work could be to ...


6

What you need is basically build topology for you vector layer. One option is using ArcGIS, convert your shapefiles to ESRI GeoDataBase, create topology using different rules defined in ArcGIS and then clean your data. Here is a short tutorial for the same. Another option is using postgis and check for dataset validation. Here is a tutorial for this.In that ...


6

First, full installation of OSGeo4W: http://trac.osgeo.org/osgeo4w/ Use the binary package(#1 under step 2). Second, fetch the Sextante plugin for QGIS, and add it. You should now be able to access the GRASS modules(I have currently 154 geoalgorithms). Source: I used this over the weekend to perform various raster analysis operations, most of which ...


5

Hiring a surveyor a Mapperz suggests is probably the most sensible thing to do if you're committed to putting a lot of money into landscaping. That said, see if there is LIDAR data available for your area. Some U.S. states provide it at an accuracy of ~18cm for free. It might be sufficient for your planning needs.


5

after obtaining the square grid, clip it with: Vector>Geoprocessing Tools>Intersect intersect it with the poligon.


5

Expanded answer based on @petr k.'s accepted answer. The example in the ESRI forum is using a URL, but I was able to knock out the src attribute and set the height to 0 in order to control my width: <iframe width="500" height="0"></iframe> In my case, I'm not concerned about the height of the window. In ArcGIS 10, I selected the "As a ...


5

You are better off using a remote sensing application. Of course, you need to have the raster imagery on your computer. There are tons of methods that can help you determine woodland areas, such as: using Neural Networks, trained patches of imagery, supervised/unsupervised segmentation and classification. I'm not sure if this solves your problem, but it's a ...


5

This worked for me using ArcGIS 10 SP1. My custom tool is not on a toolbar: Dim UIDCls As ESRI.ArcGIS.esriSystem.UID = New ESRI.ArcGIS.esriSystem.UIDClass() ' id property of menu from Config.esriaddinx document UIDCls.Value = "ClassLibraryAddin_MyTool" Dim document As ESRI.ArcGIS.Framework.IDocument = My.ArcMap.Document Dim commandItem ...


5

Maybe Multitemporal Multivariate data visualization plugin for QGIS is closer to what you're looking for. Screenshot: http://www.bernawebdesign.ch/byteblog/wp-content/uploads/2011/04/multiview.png


5

It's not very complicated to do, but I tend to just use this webpage. But let's work through the latitude in your example. The decimal degrees are the same, in this case 41. Now, take the remainder and multiply by 60. This gives you 35.44998. The integer part is the seconds (35'). Now, take the remainder and multiply by 60 again. You get the seconds ...


5

One possibility might be to create a new file geodatabase, set your current workspace environment to it, do your processing, and at the end delete the file geodatabase.


4

Great question Charles. They are both. GIScience has a much bigger scope and depth. GIScience investigates better methods, methodologies to achieve something. For instance, developing an new algorithm to process remote sensing imagery and extract certain features. GIS is a tool, used by others to achieve desired results. A GIS user uses certain algorithms ...


4

Look this python library https://github.com/ewheeler/PyDecimalDegrees or this online/offline scripts based on Perl http://www.movable-type.co.uk/scripts/latlong.html


4

I had the same issue a while back. It's a pretty easy fix, just use the the describe tool. Your already getting the layer name from your parameters. So all you have to do is describe the layer, find the path then merge the two. layer = arcpy.GetParameterAsText(0) desc = arcpy.Describe(layer) path = desc.path layersource = str(path) + "/" + layer That ...


4

I think an error like yours, seen when you try to Start a Geoprocessing Service either manually or as part of Add New Service (i.e. when it is first created), is likely to be due to trying to start too many Geoprocessing Services for the resources the hardware hosting them has available. If you Stop one or two others then you should be able to Start this ...


4

It sounds like you are dealing with a graphic so use the Select tool on the Draw toolbar to select. Then on the same toolbar under the Drawing pulldown you should be able to Convert Graphics To Features so that you can edit it. Alternatively, once you have it selected you can use the Delete key (or Edit | Delete) to delete it. Edit | Select All ...


3

@ MaryBeth - You have valid concerns, It probably is not ever going to be as easy to "draft" in arcmap as it is in autocad, or microstation, or "Their/Your CAD System Here". *EDIT: * what's new There are some SUPER nice features however that I am beginning to really love in desktop 10. ESRI has come a long way to making or facilitating a (used to be ...


3

DIY Survey on the cheap is going to be either inaccurate (cheap equipment) or costly. Ideal renting a viva gs09 rtk would be your best bet http://www.surveyequipment.com/gps-survey-equipment/viva-gs09-rtk (Requiring only the GS09 SmartAntenna and CS09 Controller) Then you need the software to create your DTM. The really dirty way is create a grid in your ...


3

It's possible to do this kind of work using close-range photogrammetry, which basically involves taking a lot of pictures and then working with them on a computer. Unfortunately, good software for this costs US$1k-$3k, and it takes some practice to use it well and to take the right pictures. It's a lot of fun, though.



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