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5

You need to make a spatial points object and then reproject that: library(sp) library(maptools) data(wrld_simpl) wrld_simpl.trans <- spTransform(wrld_simpl, CRS = ("+proj=moll +lon_0=0 +x_0=0 +y_0=0")) plot(wrld_simpl.trans, col = 'lightgray')) latitudes <- c(-30, 0, 20, 50) longitudes <- c(-20, 10, 50, 80) Make an SPDF: pts <- ...


2

las2las flightline_002.las --a_srs EPSG:32632 doesn't modify flightline_002.las. Rather, it creates a new file called output.las with the spatial reference information. output.las is the default value of the -o [ --output ] option available in las2las. To specify the new filename, use the following construction: las2las --a_srs EPSG:32632 ...


1

This needs several steps: The borders are freely available from Natural Earth Using QGIS, you can reproject the data to the Gall-Peters projection. You need to create a custom CRS for it: "+proj=cea +lon_0=0 +x_0=0 +y_0=0 +lat_ts=45 +ellps=WGS84 +datum=WGS84 +units=m +no_defs" Exporting to SVG is not supported directly, but you can install the ...


9

From the links posted as comments I identified a couple of misconceptions I had about projections and gathered this quick summary. It should be mentioned that many projections don’t truly preserve any attribute. Their intent is typically to minimize all types of distortion thereby not eliminating it in any specific property. Jack of all trades, master of ...


2

This is happening because in your manual workflow your feature class has a different coordinate system than the data frame, so there is a transformation on-the-fly going on. However, in your automated workflow you are reprojecting the feature class and then calculating area. Depending on the shape & size of the polygon, and the location, these two ...


2

No problem for QGIS: Write the coordinates of both points in decimal degrees into a text file: Name East North Tokyo 139.75 35.6667 NewYork -73.96667 40.78333 Load the points file as delimited text Create a aeqd projection on one point using a sphere: +proj=aeqd +lat_0=40.78333 +lon_0=-73.96667 +x_0=0 +y_0=0 +a=6371000 +b=6371000 +units=m +no_defs ...


0

Turns out that the problem was the field of view on my camera. I lowered it and with a little tweaking everything looked exactly the same. In addition to that I made some lat/lng debug points on the sphere and they matched up perfectly, so I knew that all of my math / projection was right.


0

Thanks all for your responses, they are the clues for me to realize what was happening. First think to notice is that when I drag and drop the raster into the dataframe in Arcmap, it pops up an alert saying “Unknown spatial Reference”, that means this raster map was not referenced and hasn’t a defined a projection. Assigning a projection to the dataset is ...


0

In case anyone is curious about what projection I ended up using for the data I was working with, it's this: var mercator = d3.geo.mercator() .center([ -73.438, 45.447 ]) .translate([ width * 0.1, height * 0.2 ]) .scale([ 8000000 ]);


0

Adjust the projection's scale since you're trying to show a small area. Here's a polygon around Montreal: https://gist.github.com/anonymous/302378c7c02cff2450231a77068c5870 Here's code to draw it with d3: https://bl.ocks.org/swingley/9441b02dd565b6caa3b9f388cbd077bb The relevant JS for defining the projection: var mercator = d3.geo.mercator() ...


0

You can add ArcGIS online map as basemap into ArcGIS desktop, to check whether your shape file is matched with the reality or not. The way to add arcgis onlie: in ArcMap->file->arcgis onLine->select the online service which is right for you(world Imagery may be ok)->click "add". Then your shape file will overlap with arcgis online data as below:


2

Try with other zone it has no problem, I guess GDAL cannot wrap it outside. gdalwarp -t_srs '+proj=utm +zone=12 +datum=WGS84 +units=m +no_defs' test.tif test_utm1.tif


0

In addition to mkennedy's response, for achieving this effect in Cesium (from https://groups.google.com/d/msg/cesium-dev/BT5z9ztSnvk/4Fpjaxh5BQAJ): Points of a polygon are connected by finding the shortest distance between those two points. Most of the time, the shortest distance will not be following the longitude and latitude lines. However, for ...


2

You can see a demo in action to illustrate. The thing to keep in mind are: load Proj4js library and the local EPSG code proj4js declaration from http://epsg.io website get the ol.proj.projection object and set it extent (for managing map resolution) var extent = ol.proj.transformExtent([-8.74, 49.81, 1.84, 60.9], 'EPSG:4326', 'EPSG:27700'); var ...


2

I usually use a function to create WMS Layers to avoid redundances. function Tile(options){ return new ol.layer.Tile({ name: options.name || 'Layer', visible: options.visible === false ? false : true, source: new ol.source.TileWMS({ crossOrigin: 'anonymous', url: options.url, params: { ...


1

To effectively use shapely it is important to first project your coordinates into a projected coordinate system that is appropriate to your region, for example, epsg:27700 if you are based in the UK. A good way to do this is using pyproj: import pyproj as proj # setup your projections crs_wgs = proj.Proj(init='epsg:4326') # assuming you're using WGS84 ...


1

Looks like ESRI decided to define their own projection parameters: http://osgeo-org.1560.x6.nabble.com/Question-about-Krovak-projection-and-ESRI-XY-Plane-Rotation-parameter-td4291471.html There has also been some discussion on the GDAL list recently: http://comments.gmane.org/gmane.comp.gis.gdal.devel/42132 I suspect the raster package is applying some ...


3

What defines which projection is a polygon based upon, and therefore which projection should apply to it? For these vertices, are the right polygons the left or the right ones? That depends on what purpose the polygons are going to used for. If their areas matter, then you should build them in an equal area projection like Albers. If 90 degree ...


7

First install QGIS plugin "Affine Transformation" from Plugins > Manage and Install Plugins.. Then start editing and navigate to vector > Geoprocessing Tools > Affine Transformation. Add your latitude value in 'y+' as encircled in the screen shot.


1

A couple things might be happening here. You have a transparency on the layer (unlikely). You have a stretch type defined in the symbology for the raster. This might be standard deviation: Set it to None and see if that makes any difference.


0

If the county map is in EPSG:2237, better leave it that way. DO NOT use Set Layer CRS to change it, that will corrupt your data. If you did, change it back. Better use Save As ... for vector data and Raster -> Projections -> Warp for rasters. Both need another filename and a different target CRS. If you are unsure, set the PROJECT CRS to EPSG:3857, ...



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