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1

The coordinates you have are in WGS 84, just note Zagreb's coordinates: 45.8167° N, 15.9833° E. Have in mind that's in degrees and it is a geographic coordinate system. If you do not know exactly the difference between a geographic coordinate system and a projected coordinate system let me know and I can link you to a good website explaining it. Just ...


2

My advice would be use both and then compare the results. Depending on the accuracy you require, you might find that the results are comparable. That is, if you round up to the nearest metre squared, the number might be the same. GDA 1994 Australia Albers is great if you are dealing with areas that cover multiple zones (i.e. measuring a polygon area that ...


5

This screenshot confirms that you have the x and y coordinates the wrong way round, as I mentioned in my comment earlier. The coordinates are in degrees, just assume a CRS of 4326 to start with. Don't worry about projections for now. Once your points are showing over Croatia, then you can re-project into a suitable local projection. x=45, y=14 will show up ...


1

Put the proj4 string between quotes. Now the string gets split at parsing and GDAL thinks that the +ellps is a name of the source file.


2

Using the EPSG works: gdalwarp -t_srs EPSG:4269 RipBuf100_09.tif RipB uf100WGS_09.tif Creating output file that is 55104P x 24192L. Processing input file RipBuf100_09.tif. Using internal nodata values (e.g. -2.14748e+009) for image RipBuf100_09.tif. Copying nodata values from source RipBuf100_09.tif to destination ...


1

shot in the dark, but maybe use the EPSG instead of the actual CRS label


1

Zone 1 covers longitude 180° to 174° W, hence it's origin is (177° W,0° N). similarly moving eastward Zone 2 covers longitude 174° to 168° W, with origin (171° W,0° N). so Zone 18 is 78° W to 72° W, with origin (75°W, 0°N)


4

Many projected coordinate systems use a false Easting and/or a false Northing to avoid negative coordinates and/or to reduce potential ambiguities with other CRS of the same region. In the case of UTM 18N, the origin of the projection, in lat long, is (0°, -75°), but the false easting is 500 000 m meaning that the XY coordinate system has been shifted. ...


1

The units of WGS84 are degrees, so your result says 79 degrees west of the Greenwich prime meridian. Generally, UTM coordinates have a false easting of 500km, so the origin is really 500km west of the UTM 18N meridian at 75° West cutting the equator.


0

Just as a quick double check, when you rotated the coordinates, you did "rotate from the center", correct? In other words, your resulting coordinates were: {x Cos[angle] + (2 cy - y) Sin[angle], y Cos[angle] + x Sin[angle]} where cy is the center y coordinate (ie, half the y width, or 3080 in your case), and angle is the angle of rotation, correct? When I ...


2

Use ST_WorldToRasterCoord(), ST_WorldToRasterCoordX() and/or ST_WorldToRasterCoordY().


2

In PostGIS you have so called raster editors to set the transformation parameters. http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Editors ST_SetUpperLeft, ST_SetScale, ST_SetSkew... And raster accessors to transform the numbers. http://postgis.net/docs/manual-2.1/RT_reference.html#Raster_Accessors ST_WorldToRasterCoord The calculation ...


2

I solve the similar problem this way: from qgis.core import * from qgis.gui import * layer = QgsVectorLayer(self.shpFilePath, "Track", "ogr") crs = layer.crs() crs.createFromId(4326) layer.setCrs(crs) QgsMapLayerRegistry.instance().addMapLayer(layer)


2

I think ideally layers which cover the same area should be in the same CRS before you load it in your application (i.e. re-save vectors and reproject rasters). This is important when conducting spatial analysis. But if it's just for displaying, you could use the following code to set the CRS for all loaded layers and the map projection (change the EPSG code ...


1

You do not need a projection if your coordinates are arbitrary. If you are going to use a basemap to pick a corner of the building provided by Arcmap then you are stuck with WGS84. Autocad offers free trial and complete student edition if you are a student. There are many open source drafting programs to choose from but your question does not state an OS ...


0

If you haven't draw it yet...maybe create a map from this site https://www.scribblemaps.com/ . This is free but if you want more than just free then there's a payment... What you can do is just draw a polygon and then save the map. Then after that you can send it to kml to bring it up Google Earth Pro .. Then send kml to ArcMap.


2

Is the raster format an Esri GRID? If so, the original LCC definition may have used NAD83 (CSRS) which isn't supported in the PRJ.ADF file format used by Esri grids. The definition doesn't match any of the existing Canadian LCC definitions, but it's close. Do try to change the geographic coordinate reference system only to NAD 1983 (North American 1983) ...


3

It looks to me like the Lambert projection file has an error. GRS_1980 is a spheroid, not a datum. The NAD83 datum is based on the GRS_1980 spheroid. I think it is possible that your Lambert projection is actually using the NAD83 datum. Your datum transformation throws an error because you are not trying to transform between WGS_1984 and NAD83. If it were ...


5

If the substation coordinates are given in latitude and longitude, the CRS can not be EPSG:32629. EPSG:4326 seems more reasonable, or a local datum with degrees as units. You should not use Set Layer CRS to cahnge the CRS, but save As ... to a different name and CRS. You can install openstreetmap background with the OpenLayers plugin to see if the stations ...


1

You may want to review the Paul Ramsey PostGIS Gotchas You Tube Video. The video link starts at the distance discussion. There are pitfalls with every coordinate system. The thing that caught my eye along time ago when I saw a similar video is that a GPS point may not be under the line that your two other GPS points draw.


0

There is the paper "Transformations between NAD83 (2011) and WGS84 (G1674)" from the US NGS detailing the process of converting NAD83 data to WGS84 data.


6

Short answer is yes. You need to convert from your coordinates' native reference frame to the NAD83 realization's reference frame, then possibly add an adjustment. In the case of NAD83(CSRS), which I use, there are 3 steps: Native RF -> ITRF96(1997.0) ITRF96 (1997.0) -> NAD83(CSRS) Grid shift Steps 1 and 2 require the Helmert transformation. Step 3 uses ...


0

Using Google Earth Pro (this is free now) Use the Measure Tool (ruler) Draw around your rooftop building as polygon save >Polygon Measure goes to the 'Temporary Places' in the Left Table Right Click 'copy' (ctrl +v) Using Notepad++ Paste as XML Coordinates are found in Polygon Tag as LinearRing Coordinates


2

There is a straightforward, disciplined way to analyze such data: linear regression. It can work because (a) the range of these points is a relatively small part of the world and (b) to a close approximation over such ranges, projection formulas are nearly linear as a function of latitude and longitude and--with more data--even their departures from ...


2

Yes, it's possible. Convert the known coordinates from lat-long into various coordinate systems and see what matches. Looking at a few of your lat-long values, it seems that your data is in California, so my guess would be California State Plane; this may be in meters or feet, but the conversion will tell you quickly.


0

In Google Earth, the yellow thumbtack tool is your 'placemark' tool you'll notice that when you click on that tool you get a yellow placemark icon in your window with an active boundary border around it. You can click the active placemark and drag it to where your building is, you will notice that as you do so, the recorded coordinates for your placemark ...


1

It is defined WKID: 102039 Put this number into the ArcGIS search bar in projections and it will show up. I agree with you this will get the shape to appear as you require. It is defined in ArcGIS so you can reproject to and from unprojected NAD 83. USA_Contiguous_Albers_Equal_Area_Conic_USGS_version WKID: 102039 Authority: ESRI ...


2

As suggested by @bugmenot123, you have to save your layer as a new layer in order to take into account the new CRS you need. Here are the steps to follow: Right-click on layer name in the Layers group (see screenshot below) Select UTM32 as a CRS Give your layer a new name > click OK Add the new layer in QGIS and check your points position


0

Finally got an answer on github: Internally, Leaflet transforms EPSG:4326 coordinates to pixel coordinates. These pixel coordinates are the EPSG:3857 coordinates divided by a power of 2 (and then rounded). It might be possible to fetch some of these coordinates (look at methods like L.Map.latLngToLayerPoint) and then multiply stuff given the zoom ...


1

Hi since your points are from a GPS track I am guessing that they have a Z-value field or an elevation field. When you configure the ThreeJS plugin in QGIS you should have the following options for the Z coordinate settings area: Relative to DEM Absolute value I did an example with point data and line data that have an attribute called elevation. I ...


2

You can set up QGIS what to do if no CRS definition found for a layer in Settings/Options/CRS CRS for new layers block. If you know the CRS of the AutoCAD drawing and CRS is not asked during open, then Load the DXF file into GIS Open the layer properties dialog and select the correct CRS for the layer on the General tab You may also change the CRS for the ...


1

Choose tab processing > toolbox After that, choose QGIS geoalgorithms > vector general tools > reproject layer Then pick the one you want.


1

Assuming your coordinates are in decimal degrees (see the answer of HeyOverThere), you just have to export your Excel file as a CSV and import the CSV following this tutorial. You may need to reproject your layer depending on its original datum.


0

If the coordinates are in degrees, minutes, and seconds you'll need to convert those values to decimal. Here's a quick guide on how to do that: http://mathforum.org/sarah/hamilton/ham.degrees.html


3

I would advise against using coordinates outside UTM boundaries as this can cause unforeseen problems further down the line when others use the data and may be unaware of this. I would consider it bad practice unless no other alternatives exist. This has been recognized as a problem in Idaho and a solution exists so why not use it? The Idaho Transverse ...


1

I think that it is acceptable to use one UTM zone for all for the sake of analysis. For longevity, a continental-scale projection (like Albers Equal Area in North America) would be more appropriate (especially for published data). We used to use UTM Zone 17 for all of West Virginia when I worked in WV even though the eastern panhandle is in zone 18. Same ...


2

The problem comes from the projection name. In Oracle, the proper name for the 2SP Lambert Conformal Conic projection is "Lambert Conformal Conic" (notice: no "2SP", spaces instead of underscores). The following definition will work: 'PROJCS["Customized Lambert", GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS ...


2

You may have used Set Layer CRS, which is wrong in most cases and corrupts your data. You better change that back, or get a fresh copy of the data. You need to use Save As ... for vector data and Raster -> Projections -> Warp(Reproject) for raster files to get the coordinates into the new CRS. Some features do not look at the OTF settings, so you ...


2

It looks like utm. This is Honolulu. UTM Easting 618,431.58 UTM Northing 2,357,505.97 Yes it is indeed. X is easting Y is northing Zone I think is 4N but check


0

Using QGIS, You have to use Save as ... for vector data and Raster -> Projections -> Warp (Reproject) for raster data to reproject the data to the same CRS, under a new filename for each dataset. Arcgis and other GIS software might be similar. Set Layer CRS is not the same, and will corrupt your data. You better start with a fresh copy of the original ...



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