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-1

To be 100% safe, use always same projections. It's because of the difference between meter and Indian yard. http://georepository.com/unit_9084/Indian-yard.html


3

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 ...


1

Google Maps Engine works with WGS84 EPSG-Code 4326, so you'll need to project the shapefile into the correct projection. ArcGIS: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00170000007m000000 QGIS: http://docs.qgis.org/2.2/de/docs/training_manual/vector_analysis/reproject_transform.html?highlight=transformation


0

You can set up a local oblique mercator projection to get the rotation, as I described in my answer here: Using customized Coordinate System for Archaeological site data Your rotation parameter +alpha would be 33.765 degrees. You have to expriment about the sign to be used. The Proj.4 parameters are listed here: http://trac.osgeo.org/proj/wiki/GenParms, ...


2

It is confusing and you might ask clarification from the professor. It may be that the professor wanted each requirement to be distinctly one thing. He/she could have written: The shapefile must have an assigned projection w/accompanying .prj file and that assigned projection must be an unprojected (geographic) WGS84 geographic coordinate system. ...


1

Using the Project (Data Management) tool, should yield you results! If you need to assign a known coordinate system to a dataset with an unknown coordinate system, the Define Projection (Data Management) tool does that.


1

Ok, So I have done some testing based on the results from the Baidu conversion tool.. My conclusion is that their SRID is a non EPSG standard (at least its not part of PostGIS spatial_ref_sys). Basically I tested 5 google maps lat/long coordinates with the Baidu converted coords relative to them, looped through every record in the spatial_ref_sys table, ...


0

Start a new, blank map document. Add your polygon layer to it. Double-click the layer in the ToC and go to the Source tab. That will tell you what coordinate system your polygon layer is in (just as an FYI). Add your table to the map. Drill down in the catalog window toolboxes to find, or type into the search window Make XY Event Layer and run it. Select ...


0

You do not mention what software you are using. While this solution is ArcGIS based, the principles of the method are the same for any software though the tools to do it and their names may differ or not be available depending on the software. You have 'artificial' coordinates for all points, and for some of those points you have 'real' coordinates. You ...


3

You need to apply the geographic transformation too. In the 10.2.5 API, project has several versions. You're going to have to switch to one that uses a Geometry and supports a GeographicTransformation instead like: public static Geometry project (Geometry geometry, SpatialReference inputSR, SpatialReference outputSR, GeographicTransformation tx) For 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 ...


1

Based on both this blog post and the answer to How can I specify the CRS of a raster layer in pyqgis?, you can achieve what you want this way: settings = QSettings() # Take the "CRS for new layers" config, overwrite it while loading layers and... oldProjValue = settings.value( "/Projections/defaultBehaviour", "prompt", type=str ) settings.setValue( ...


3

You have to create a custom CRS with miles as units, like +proj=lcc +lat_1=33 +lat_2=45 +lat_0=39 +lon_0=-96 +x_0=0 +y_0=0 +datum=NAD83 +units=mi +no_defs Then save your data to that CRS and turn on-the-fly-reprojection OFF. Unfortunately, the distance tools still writes km as unit, but the USA is about 2886 miles wide, while it is 4649 km in the ...


1

The following code should allow you to add a vector layer without the CRS popup window from appearing (atleast it doesn't appear for me): from qgis import * from qgis.utils import * #replace "shapefile_path" with your layer's path; replace "Layer_name" with whatever name you want to give the layer in the TOC ...


0

You do accomplish your goal with projection, but the "making UTM uniform" or "change data to same UTM" is incorrect. A UTM zone is designed to cover a specific area with minimal distortion and that area is smaller than the US. You need a single projection designed to cover the entire US with minimal distortion - there will be more than in a UTM projection, ...


1

If you have to deal with the whole United States, you should use one of the Contiguos projections: ESRI:102003 USA_Contiguous_Albers_Equal_Area_Conic ESRI:102004 USA_Contiguous_Lambert_Conformal_Conic ESRI:102005 USA_Contiguous_Albers_Equal_Area_Conic You can reproject your UTM data to one of those CRS, then combine them.


1

The easiest way to get the projection information is Rightclick -> Set CRS for Layer. This will report the USER:100000 you already know, and the parameters for the projection as well. +units=... will give you the units of the projection.


1

You should use the Project Raster function with WGS1984 UTM Zone 37N as input coordinate system and Adindan UTM Zone 37N as output coordinate system. The input coordinate system should be entered automatically if it is defined on the raster. However, the fact that they don't overlap in Arcmap suggests that's not the case for either your raster, shapefile ...


0

Essentially what I'm saying in my comment is that you should not change the CRS for those other layers but instead load them and use Save As to change the projection.


2

I have put a projection setting in your source definition and it seems to work: var vS=new ol.source.GeoJSON( ({ "object": data, projection: 'EPSG:3857' }) ); This is the result: http://jsfiddle.net/zzahmbff/3/ Perhaps this resource can help you to see different ways to load vector data: ...


0

Try this. In your attribute table. Right click on the field header (Shape_Area) and select Calculate Geometry.... You will see the screen below. Make sure you set your units correctly and that the Coordinate System specified is the correct one. Let it calculate and then compare to your original. Run in Edit in case you don't like the results


1

I think what happened is that the original data is in lat/lon. Somehow it was assigned the UTM coordinate reference system, and unprojected to WGS 1984, a geographic coordinate reference system. Having "Y" or latitude values near zero that should be at mid-latitudes is a classic sign of a mistaken UTM definition for latitude/longitude data. I don't know ...


2

There is definitely something wrong with your shapefile - viewing it in QGIS, the extents are: -85.489443389,0.000406358 : -85.489443375,0.000406369 ... placing it somewhere off the coast of Equador. Another clue: the difference in X extents (-85.489443389 - -85.489443375) is 0.000000014 decimal degrees - which makes the whole cemetary something around ...


2

You need to use ST_Transform. For example, taking a point somewhere in Southern India (which I'm guessing from the UTM zone and your profile is the area you are interesting in) SELECT ST_X(geom), ST_Y(geom) FROM (SELECT ST_Transform(ST_SetSrid(ST_MakePoint(627516, 1413990), 32643), 4326) as geom) g; or in your case, if you have a table already with ...


0

The conversion code was supplied by peterv6i in this thread. http://forums.sideimagingsoft.com/index.php?topic=7785.msg48682#msg48682 public static double MMtoEllipsiodDegLatitude(double Lat_m) { if (Math.abs(Lat_m) < 15433199.0D) { if (Lat_m != 0.0D) { return Math.atan(Math.tan(Math.atan(Math.exp(Lat_m / 6378388.0D)) * 2.0D - ...


2

I used the ogr java bindings: public static void unitOfCRS(){ SpatialReference poSourceSRS = new SpatialReference(); // output: metre poSourceSRS.ImportFromEPSG(3068); System.out.println(poSourceSRS.GetAttrValue("UNIT")); // output: degree poSourceSRS.ImportFromEPSG(4326); ...


1

You could perhaps look into the PROJ4 library. There seems to be a Java binding, which you could use. I am almost confident that I have done a similar task before, although with Python, but I cannot find my code to double check. Either way, there should be a way to get a string which includes all the parameters of a specific coordinate system. You would ...


6

It is correct to use an equal area projection in order to compute the area of your polygon. However, in your case, you should be aware that only the vertices of a polygon are projected when you change the coordinate system. Between the vertices, straight lines are then interpolated (but if you have a huge polygons, those lines should have been curves), ...


1

The proj4text strings have been saved with a single trailing whitespace, which is why your query returns nothing. Use the trim operator: SELECT * FROM spatial_ref_sys WHERE trim(proj4text) = '+proj=utm +zone=51 +south +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs';


0

as whuber said, there are several pages of explanations to get the exact formulas. Though you can find some simplified series on wikipedia. For Wisconsin Transverse Mercator, please also note that implementing the projection is not enough, because you also need to code the datum transform between WGS 84 and NAD 83. My suggestion is to take advantage of ...


1

Just incase some had the same problem as me. The lat and long fields dont change their values when you do the correct projection. Once you are in the correct projection system in the dataframe, and you export the data using that GCS projection system, you then add the layer to the dataframe. Next, you need to go to the attributes table for that new layer. ...


0

The solution is to add a dummy layer. We can create a "fake" feature layer from JSON to trick the map into the desired projection. This feature layer should have the target spatial reference. var layerDefinition = { "extent": { "xmin": 0, "ymin": 0, "xmax": 0, "ymax": 0, ...


3

Yes, but to explain why: I can tell that you have projected coordinates (as I assume you're in New Zealand) the numbers are quite large, much bigger than -180 to 180, which is probably New Zealand Transverse Mercator 2000: Projection type:Transverse Mercator Reference ellipsoid:GRS80 Datum:NZGD2000 Origin latitude:0° 00' 00" South Origin longitude / ...



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