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3

The length functions work differently with 3D linestring geometries: ST_Length - returns 2D distances for geometry types, and oddly 3D distances for geography types (but not in this question) ST_Length_Spheroid - returns 3D distances for geometry types Your example is in 3D, so it will calculate the 3D length with ST_Length_Spheroid and the 2D length ...


3

In QGIS, the projection string for EPSG:3399 is: +proj=tmerc +lat_0=0 +lon_0=15 +k=1 +x_0=5500000 +y_0=0 +ellps=bessel +units=m +no_defs This projection string has no datum shift +towgs84, which I would expect for every transformation from the German DHDN/bessel to the WGS ellipsoid. See this page in German for more information on official transformation ...


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Yes. Double-click the dataframe name in the Table of Contents, or right-click it and choose Properties. On the Coordinate System tab, at the bottom, click the Transformations button. This will bring up the same dialog as when you add the layers. Here you can select the CRS of the layers present in the top box, the CRS you want to specify them to (your ...


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You do not need to transform the points. The projection applies to the location, not to the attributes (which could be in knots, or ms-1, or nothing to do with any units, like the colour of the soil). The only potential case where this could be a problem is where the target CRS is rotated from the source CRS. Then you'd may need to project u and v into the ...


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The EPSG: 3857, WGS 84 / Pseudo Mercator in QGIS is called WGS84 Web Mercator (Auxiliary Sphere) in ArcGIS. You are simply not using the right projection.


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Here is a tested solution: Install comtypes and snippet102 (How do I access ArcObjects from Python?) with your python installation use the following python function (based on comtypes). Make sure ArcMap is open. It is tested with rotated dataframes. Python code: def MapCoord_2_PageCoord(mapX,mapY): from snippets102 import GetLibPath, InitStandalone, ...


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Original layout: Script: import arcpy, os, traceback, sys,time import numpy as np from math import radians,sin,cos try: def showPyMessage(): arcpy.AddMessage(str(time.ctime()) + " - " + message) def Rotate(xM,yM,angle,xc,yc): x=xM-xc;y=yM-yc a=radians(angle) xN=cos(a)*x+sin(a)*y yN=-sin(a)*x+cos(a)*y ...


3

I think the first thing I would do is trace the original source of the data and ask for the original CAD data used to create the drawings. If it was done by a third-party under contract to your organisation, then they may have an obligation to supply the data. Even if it was done by a third-party, a polite phone call often works wonders. Even if all they ...


2

Typically, NAD83 and WGS84 are within one meter of each other. Your concerns about differences of 2.5 feet, which are less than a meter, indicate you do need to perform this datum transformation. Briefly, this calculation requires knowledge of when the coordinates were collected so that their movement over time can be accounted for (primarily due to the ...


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Yes you can get them to work together. Below is a sample of code from a php page I coded that uses proj4js, mine is slightly different going from a state plane into wgs84 but the concept is the same. (The syntax is a little off as I had problems pasting it into a code block and my code is sort of spread all over the place in a couple php files but I think ...


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NSRS 2007 and CORS 96 are functionally equivalent. The NAD(CORS96) realization only includes the CORS stations. The passive marks were subsequently re-adjusted based on GPS observations from the CORS using CORS96 positions. This re-adjustment of the passive marks is referred to as NSRS2007. The current realization is NAD(2011). In many places the ...


2

You need to define you own projection system: Find you x0 and y0 (the origin of you system) based on the points for which you know the real coordinates In the Coordinate Reference system selector (right click on a layer and Set Layer CRS), use user-defined coordinate-system (use the definition of the CRS you mentioned as "real coordinate" and change your ...


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Either the WGS 1984 in the original raster, or in the target UTM doesn't match Esri's definition of WGS 1984. It's probably one of the names. If it's the original raster, try using the Define Projection tool to reset it to Esri's WGS 1984 definition. If it's the output coordinate system, try using Esri's version instead.


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You can test it with gdalsrsinfo http://www.gdal.org/gdalsrsinfo.html gdalsrsinfo epsg:3068 PROJ.4 : '+proj=cass +lat_0=52.41864827777778 +lon_0=13.62720366666667 +x_0=40000 +y_0=10000 +ellps=bessel +towgs84=598.1,73.7,418.2,0.202,0.045,-2.45 5,6.7 +units=m +no_defs ' OGC WKT : PROJCS["DHDN / Soldner Berlin", GEOGCS["DHDN", ...


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EPSG:3575 is a Lambert Equal-Area Azimuthal projection centered at the North Pole. Although it uses the WGS84 datum, the underlying calculations for this ellipsoid are performed by making a (small) equal-area deformation of the ellipsoid to a sphere (using authalic latitudes) and then applying the spherical projection formulae. Thus, it suffices to ...


2

A very simple brute force approach: take the first points coordinates and convert them from ISN93 / Lambert 1993 to WGS84 degrees using cs2cs in the OSGEO4W shell cs2cs +init=epsg:3057 +to +init=epsg:4326 -f "%%.8f" <ISN93.txt >WGS84.txt build a local omerc CRS on that point, with the "local coordinates" as false Easting and Northing convert the ...


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I set the data frame projection to WGS84 Web Mercator (Auxiliary Sphere) as suggested by Nahas and this didn't change the end result. However looking at the previous thread supplied by Vince (QPJ files on ESRI software) the answer at the bottom suggested deleting the prj. and .qpjs files then bringing the data in. I did this, assigned projection to WGS84 ...


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self.coordTransform = self.coordinateTransformation(4326,3309) It looks like you have your source and destination coordinate systems mixed up.


2

ArcMap has this wonderful feature called on-the-fly transformation. Once your first layer is added to a blank fresh map (e.g. a new MXD), the map takes the layer coordinate system (more precisely spatial reference). Any layer added after the first layer, will be automatically transformed to the map spatial reference, in order to overlay with the first layer. ...


2

Oh Canada! Your strange and awkward projections! It looks like your data is actually in MTM (Modified Transverse Mercator) projection. Not since Gauss-Kruger has a Transverse Mercator projection caused so much confusion with UTM. You probably reprojected the data, because those XY coordinates in your attributes with the UTM 8 projection would put your ...


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First you need to drop the srid constraint you have on your table. Even with an unconstrained geometry type, you can have the srid check in the typmod column definition so no need to resort to constraint ALTER TABLE jake DROP CONSTRAINT enforce_srid_geom; ALTER TABLE jake ALTER COLUMN jake_geom geometry(Geometry, 2163) USING ...


2

If you don't know the datum or coordinate system for a pair of latitude/longitude coordinates, then the coordinates are ambiguous. Ambiguous coordinates means any transform or comparison between them will most likely have incorrect results.


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What you need is affine transformation and it should be easy to do with Python: You'll need GDAL GeoTransform (and it seems like you have all you need for it): gt[0] /* top left x */ gt[1] /* w-e pixel resolution */ gt[2] /* 0 */ gt[3] /* top left y */ gt[4] /* 0 */ gt[5] /* n-s pixel resolution (negative value) */ And then having your x,y: geo_x = ...


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I guess you stumbled over this note on page 53: subsequent civilian adoption of the systems usually ignores the zone prefix to easting. Where this is the case the formulas below do not apply: use the standard TM formula separately for each zone The formulas on page 54 should only be used if the zone number is written before the false Easting, which ...


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This is the answer. Sometimes you have to go through all the process of asking a question to understand the solution. JavaScript: /** * Converts spherical web mercator to tile pixel X/Y at zoom level 0 * for 256x256 tile size and inverts y coordinates. * * @param {L.point} p Leaflet point in EPSG:3857 * @return {L.point} Leaflet point with tile pixel ...


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I would look into using the proj4.js library to transform your coordinates programatically using javascript. From the Github Readme: Basic usage: proj4(fromProjection[, toProjection2, coordinates]) eg: ``` var firstProjection = 'PROJCS["NAD83 / Massachusetts Mainland",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS ...


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Here is one option using ArcGIS if the point data is regularly spaced: Create a feature class (fc) for each of the coordinate x/y pairs (R,M,L) Merge fc together from step 1 Use Create Fishnet tool to create polygon layer (you will have to define the number of columns and rows or cell height/width value) You may have to do some clean up using various ...


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If you have one data value per line, I suggest to take the middle coordinates, and import coordinates and value as point data. In a second run, you can interpolate the data of different runs into a raster, if they are neatless. UPDATE If you are only interested in the swath polygon, I suggest to import the left and right coordinates in two runs as lines ...


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Postgis is correct. Your line is in 3d space, and in fact has a length of ~482m even in the British National Grid. 338 meters is also correct but it corespondents in the projection of the 3d line in the 2d space. with a as ( select st_Geomfromewkt('SRID=27700;MULTILINESTRING(( 423216.279 574665.249 0, 423206.315 574708.077 44.649, 423158.458 ...


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The CTS wiki https://github.com/orbisgis/cts/wiki/Create-a-new-CoordinateReferenceSystem-from-a-reference-code has been updated to include a full example now. The adding of the appropriate registry was missing from it previously. After creating the CRSFactory instance, the appropriate registry has to be added to its registry manager. In this case I wanted ...



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