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0

Seems like the settings are not stored correctly. Here's the bug report for future reference http://hub.qgis.org/issues/11713


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Some things to consider: (1) Your problem is generally known as spatial interpolation because points are distributed in space, or surface interpolation because you are estimating the height of a point on a "surface" (which might be physical or abstract). (2) It's not generally a good idea to label to points in space as X,Y,Z because those letters are ...


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had the same problem and found no tools that would give me the solution, so what i did was take the LineString (which is not the feature, but the feature's geometry => feature.geometry), get its vertices and store them in an array (points) function onFeatureSelectLineString(event) { var feature = event.feature; var points = ...


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This sounds like something I would investigate using the Data Comparison toolset to assist with: The Data Comparison toolset contains tools to compare one dataset with another dataset to report similarities and differences. You can use these tools to identify changes made to a dataset. In particular the Detect Feature Changes tool which: Finds ...


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If you don't want to script a solution, there is a relatively easy way to achieve what you want using the editing tools (it is a lot easier to do than describe so don't be put off): Create a line layer and make it editable. In Settings->Snapping options set snapping on your point layer, the land layer and your new line layer. I usually use something ...


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You can find methods to create lines from points on this post. How to draw lines from two points in a CSV? So you need to add one pair of coordinate from your point based on your orientation and this defines your lines. This is basic trigonometry, but you should make sure that you work in a conformal projection (e.g. Mercator) if you want to preserve the ...


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If you need high accuracy distances, or "ground" distances, you need to convert your UTM "grid" distances (which you do indeed calculate via pythagorous) using a combined scale factor. This removes the distortion introduced by the combination of (a) reducing the horizontal distance at its elevated (above the ellipsoid) position on the earth and (b) ...


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The best way I can think is to get two UTM points, convert them to Lat/Long, and compare their geodesic distances to their UTM pythagorean distance. E.g. Take a point from this example: The CN Tower is ... in UTM zone 17, and the grid position is 630084m east, 4833438m north. So if we take A (17n 630084 4833438) and move it 30 km east, we get B (17n ...


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As commented by @whuber: As ratios of two lengths, scales are inherently unit free. Some maps describe their scales as ratios of lengths in different units (such as feet or miles per inch)--and when they do, they are usually clear about what lengths are involved. In other words, the term "unit of measurement for scale" does not make sense to use. ...



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