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from what I understand, you have a single ungeoreferenced image, and you want to find the extent. This can be done in QGIS QGIS - Using Capture Coordinate If this is an urban map with details in the corners, you can manually match up the corners using the Capture coordinate plugin. start with an empty project Install the OpenLayers plugin (this goes in ...


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No solution, but two ideas: 1) You could create a list of GroundControlPoints (GCPs) with the lat and long coordinates and the numbers of column and row of the images. Loop through the lat-and long-images and select those values for ever (umpteen) pixel. Then you can use this list of CGPs to georectify/warp your image "image to map". 2) You can create a ...


2

you can't really convert convert distances in degrees into meters as the size of a degree varies as you approach the poles. convert your locations into a projected coordinate system, then calculate your distances.


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Yes, it is called GeoNames (which you have a geonames tag for) although I cannot guarantee that it has every town in the world: A daily GeoNames database dump can be downloaded in the form of a large worldwide text file (allCountries.zip). Additional country files are available for convenience. You find the files on our download server. Read the ...


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I found some help from this gis post: How to convert projected coordinates to lat/lon using Python? and made a python function to solve my problem def convertEPSGtoWGS(pointX, pointY): # Spatial Reference System inputEPSG = 3857 outputEPSG = 4326 # create a geometry from coordinates point = ogr.Geometry(ogr.wkbPoint) ...


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I agree with Micky T, it looks like you are using the wrong proj4 string. First, you will need to ensure which projection your numbers are in. WGS84 is the datum, not the projection. One possible projection is UTM, which defines your starting point for your easting and northing in meters. The x and y values that you give sure look like they are a ...


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Your data is in LAT/LON (WGS84) but the X and Y columns are in a projected coordinate system, likely something like UTM or State Plane. So all you have to do is create 2 new columns for the Lat and Lon, and populate them like this: How do I calculate the latitude and longitude of points using QGIS?


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One solution (and a great chance to implement itertools) would be: import arcpy, os, itertools infc = r"C:\MyFolder\MyGDB\MyInputFeatureClass" # Replace with the path to your input feature class outfc = r"C:\MyFolder\MyGDB\MyOutputFeatureClass" # Replace with the path to your output feature class spatialref = arcpy.Describe(infc).spatialReference if not ...


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Have a look at "Extreme points of Canadian provinces" from Wikipedia.


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I was able to figure it out with a work around. I added the Lat/Long Fields and then us Convert Coordinate Notation. That generated a new feature class with two new fields: DDLat and DDLon. That got me what I needed even though I had to add a couple additional steps. The output was 076.###W, 37.####N as opposed to what I wanted which was (-76.###, 37.####) ...


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I think another way of doing this is to just add the text file to ArcMap, display by x,y coordinates, and join to your to your original shapefile. You can then export the resulting shapefile (or just the table) as whatever you want.


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This is a reasonably simple problem to solve in ArcGIS. Open the Shapefile (it's not a "raster shapefile" btw; there's no such thin). Add two fields to your shapefile. One for Lat, one for Lon. Both should be of type Float or double. Populate one of these fields with the X, and one with the Y value for the point. (Using "calculate geometry"). Now, create ...


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As stated in the tool documentation for Calculate Field: Python expressions can use the geometry area and length properties with an areal or linear unit to convert the value to a different unit of measure (for example, !shape.length@kilometers!) These expressions are not usable with points or individual coordinates. Fortunately, you can use other ...


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If you have some unique ID in both layers which you can use to easily join values to new layer from old one, it is piece of cake. But this doesn't seem like that case. If not, it is pretty difficult problem. I wonder why comment from user30184 suggesting to use OpenJUMP and plugin http://www.vividsolutions.com/products.asp?catg=spaapp&code=roadmatcher ...


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You can use Open Street Map Nominatim API for Geocoding and it will return the bounding box Example: Manitoba, Canada http://nominatim.openstreetmap.org/search?q=Manitoba,%20Canada&format=xml&polygon=1 Response (xml) boundingbox="49.9971285,49.9972285,-96.8892673,-96.8891673" ...


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You can download Country Boundaries from Natural Earth: http://www.naturalearthdata.com/http//www.naturalearthdata.com/download/110m/cultural/ne_110m_admin_0_countries.zip Found here: http://www.naturalearthdata.com/downloads/110m-cultural-vectors/


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This is a great question, I had to do something similar recently but with a much smaller dataset, so I was able to use a simple intersection with some extra visual quality checking and it was fine. But here's an idea for this, though I don't have code, and it's kind of a hefty process. Definitely test with a sample from the full dataset first. You can ...


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I much prefer the answer from @dmh126 as his method allows your red_line layer to be updated quite easily. Just to add an alternative, you can use the Join attributes table tool from the Processing Toolbox and select your layers with the common field. Note that this method creates a new shapefile instead of updating an existing one:


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If you want to add some attributes from red layer to blue layer and one attribute is common in both layers, you have to use Add Vector Join. I've written about that here. Right click on your red shapefile layer on Layer Panel and choose Properties. Then go to Joins tab. Press the + button, it will create new join. Join layer is your red shapefile layer. ...


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You are correct. A geohash rectangle of precision N characters will always be fully contained by the corresponding geohash of size N - 1 containing all the same preceding characters.


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180 degrees of latitude = 7200 0.025° sections from pole to pole 360 degrees of longitude = 14400 0.025° sections along the equator 7200 * 14400 = 1.0368 * 10^8 0.025°x0.025° squares (not actually squares)


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Disclaimer: Any method you use to do this, especially with a consumer GPS unit, is going to be an approximation at best. If you truly want to know where the boundaries are, you will need to locate property pins/corners which might require a metal detector. Your best, safest option is to hire a professional land surveyor. No, those are not lat/longs in the ...



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