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One of the fastest and easiest possible solutions uses a short program written with the free open source program R (the R project for statistical computing). The following code computes the distance matrix (using spherical distances) between two arrays of (lon, lat) coordinates named customers and facilities and stores it in an array distances (with rows ...


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This is a fairly big question, a good place to start would be investigating different client-side api's for creating web maps. Some great ones include: leaflet esri's javascript api mapbox google maps Part of your decision will be based on if your application will be commercial. If so, I recommend leaflet. These api's also tie into different ...


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If you take the G in GIS for Geographic then the answer is no. If you take the G in GIS for Geodetic then the answer is maybe, but not any time soon. There are two main issues with Geoprocessing in the Geodetic domain: 1. Calculations are way more complex, time consuming and uncertain. Take for instance the distance between two points: should it be ...


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Due to various vagaries in the ArcGIS software, I'm going to tell you to use different coordinate reference systems. That will let you access the predefined transformations and hopefully make your life easier. Use WGS_1984_Web_Mercator_Auxiliary_Sphere instead. This one uses WGS 1984 for the geographic CRS (aka datum). The one you're using, ...


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I think you may need to process this file yourself - either manually, or by writing a script to automate the extraction. If you rename the file GMRT.kmz to GMRT.zip you can open it in WinZip or similar, and see its contents. This includes the file doc.kml, which contains a number of Links - examining the first link shows a URL: <Link> ...


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Apply below transformation method to project your data in ArcMap. 1)Open New Arcmap. 2)Add your Imagery files which you downloaded from Google earth. 3)Add your existing geodatabase layer files into arcmap (Ex:Layers or shapes) 4)Right click in the Arcmap window and select Dataframe Properties. 5) A New window will open and then select your Layer file ...


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Some great examples in the links there! One thing not mentioned in your links, which should be useful, is OpenLayers' Strategy.Refresh call. In this you can set a time interval for refreshing a vector layer automatically. Also, I create 3D animated landscape visualizations for public participation in planning and they are stand-alone (not web-based), so I ...


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Not the operating system you want, but BaseCamp by Garmin can read your kml file, and exporting to csv gives a file that can be added with delimited text to QGIS. The data leads to Indonesia. EDIT Unfortunately, KML is not a very strict standard. That means that almost every form of data storage is allowed, as long as it is valid XML. The kml drivers ...


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The "Precomputed datasets" can be loaded into the Google Earth standalone client as follows: View the source of the Earth Engine webpage (https://earthengine.google.org/#intro) Search for the galleryMetadata object, which is a list of dataset definitions. Within the galleryMetadate object, the "Precomputed datasets" will have a attribute named "kml" whose ...


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Instead of creating a KML file then using that to access Google Earth, you can instead add your GeoServer WMS directly as an overlay as below: From the menu select Add, select Image Overlay, give the overlay a name select the Refresh tab select WMS Parameters select the Add button next to 'WMS Server:' drop down Add the URL to your service (without ...


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Something to keep in mind is that portolan chart navigation maps like Piri Reis don't a have coordinate system, rather they are several different local coordinate systems munged together -- each one of the rosettas or compass rose like symbols is a projection source of origin, loosely speaking. So you can't just georeference the image in the usual GIS way ...


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There is a raster version of the Map You can digitise from this source for personal use. KMZ http://www.gearthhacks.com/dlfile12068/Piri-Reis-Map.htm


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See these examples mainly related to transportation UK London tube Netherland example Switzerland example Leaflet animated marker plugin PS: Not Qgis related but can answer to the need


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Based in QGIS Underdarks's Tutorial Layer “start_flash” is a medium sized dot that marks the appearance of a new tweet. Layer “big_flash” is a bigger dot of the same color which will appear after “start_flash”. Layer “permanent” is a small dot that will be visible even after the flash vanishes. ...


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Checking out the same spot in Google Earth gives an attribution to Landsat, so this data most likely came from Landsat 7 with SLC-Off. A small mirror broke on Landsat 7 that corrected for the ground movement of the satelite. There are post-processing techniques that can partially repair the image, but they probably cause artifact like the ones you see.


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If you look carefully the striping runs across the whole image, although it is clearly more visible over the lake body (due to its particular reflectance in that moment). This is probably an image noise issue related to some problem on the satellite sensor that captured the image. Have a look at the following links for some more information about this: ...


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I have updated the kml by creating java class using jdom library.For that i need to do some manual task. Remove kml tag and then process file. Here is the class i have created for this import java.io.File; import java.io.FileWriter; import java.util.Iterator; import java.util.List; import org.jdom.Document; import org.jdom.Element; import ...


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Ok so I've found one way to do this. However, it requires uploading your content to the "Google Maps Engine" service, quote: Upload the terrain data source(s), specifying information about the data and type of masking. Process the data. Create a layer and add the data. Multiple terrain data sources can be added to the same layer. Process the layer, then ...


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The answer (of course) is "it depends". Google earth isn't a single set of data - its a sequence of images, and some of them are more accurate (better aligned) than others. Things change over time too (tides, storm erosion are all factors at the sort of island scale you're considering) Note: In terms of deriving product - you are probably not compliant with ...


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Currently, the z values from Google Earth are PROBABLY relative to the EGM96 geoid model. AHD (Australian Height Datum) is another gravity-related vertical datum. I think you should do some comparisons. Check the values you can get from Google Earth against some existing AHD values. Secondly, use the EGM96 geoid model to convert the GE values back to ...


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You can load your Excel file into a Google Fusion Table, Geocode, then use the share option to create the KML. https://support.google.com/fusiontables/answer/2562055?hl=en&topic=2573107&ctx=topic


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I have downloaded the ASTER data you mentioned, and got an offset of around 120m. I'm afraid that's all the ASTER database is able to offer. They promise an offset of 20m at 95% of the world, but you can not rely on that. The data is in WGS84, same as Google Earth. So it is not a matter of datum shifts at all. If you want a more precise shoreline, you ...


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If you need ruler distance, You can use the distance matrix tool in Quantum GIS. Quantum GIS can read your KMZ files. Then you can easily compute the distance matrix. Here is tutorial http://qgis.spatialthoughts.com/2013/04/tutorial-nearest-neighbor-analysis.html


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Datum transformation are never fully accurate, which could explain a small shift but not a difference of 30 to 40 m. A difference of 30 to 40 m is more like an error due to the absence of datum transformation, or it could be an error in the dataset that you use for the relative evaluation of your position (Google registration can be wrong in some places of ...


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Get the x,y coordinates of the boundaries of countries from the following website Natural Earth (thanks, Devdatta Tengshe) which has more accurate data than others I've tried. Then use ArcGIS 10.2 to open the map shape file and select the boundaries you need. Go to data management tools --features-- features vertices to points and open the generated table. ...


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Typical - after spending hours on this, I realised the answer a few minutes after posting the question to Stack Exchange. At least others can learn from my stupidity. I needed to add a 3rd control point, in order to allow the affine transformation to apply the correct adjustment:


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For plane cartesian coordinates, it will depend on the projected coordinate sytem that you are using. But if you use a plane coordinate system based on the same geographic coordinate system than your decimal degrees, then you have an exact conversion. Otherwise, the error mainly comes from the definition of the height above the ellipsoid, but this error can ...


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import your KMZ in arcGIS using "KML to Layer". you can then use the "near" tool in arcgis.(http://resources.arcgis.com/en/help/main/10.1/index.html#//00080000001q000000) for "straight line" distances. For real distance, you need the Network analyst extension and the road network in a vector format as well (see ...


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You have not said how you converted the KML to shapefiles. Maybe something has gone wrong in that step. KML has some features that shapefiles don't allow and QGIS can not work with (like MultiGeometry), which might lead to an empty layer. You can activate the feature counter or look up in the attribute table if there are entries at all. Furthermore, you ...


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The Easiest way to do this before you add the data or imagery is : 1) Open Arcmap 2) right click the Layer properties 3) Hit the Coordinate System tab. 4) if you have the 10.0 or later: Type the name of the coordinate system ie:(WGS 1984 Web Mercator (Auxiliary Sphere)). 5) Select it. 6) Bring in the data 7) right click on the data and select Data to ...



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