Questions tagged [angles]

From Wikipedia: In geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles are usually presumed to be in a Euclidean plane, but are also defined in non-Euclidean geometry.

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14
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1answer
280 views

What is the meaning of this linear scale of angles on this 1951 map of Iceland from the U. S. Army Map Service (AMS C762)?

On the U.S. Army Map Service (AMS C762) 1:50,000 maps made of Iceland 1948–1951, there is a scale marking at the top which shows degrees, I suspect angles. In the image below it shows 25°–29°. It ...
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2answers
97 views

Distance to a ridge as function of angle (Python)

No success googling this for a while, but likely I just don't know correct terminology. Also, tell me if you see another exchange more suited for this. Given: A boolean 2-dim array that stores if a ...
7
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1answer
2k views

Is there a way to interactively rotate labels in QGIS using any of the edit tools? [duplicate]

I seem to have put too much detailed information in my previous question, confusing the masses. My apologies. Let me try again from a different angle. I want to rotate labels interactively/visually,...
7
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1answer
4k views

How to measure angle in QGIS

While measuring an angle in QGIS using measure angle tool, it is showing as 0 to 180 degree for clockwise direction and -1 to -179 for anticlockwise. What I need is, interior angle between vertices of ...
7
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1answer
2k views

Measuring Angle of two Points from North in ArcGIS 10.3 C# SDK

What is the most reliable method to calculate angle of a line from north, defined by it’s from and to points? I used to use IMeasurementTool interface found in defense solutions namespace found in ...
6
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2answers
1k views

Find lower left corner of a rotated polygon

I am currently struggling with a mathematical problem and can't seem to get it solved. I have a bunch of rotated rectangular polygons (solution should also work for non-rectangular polygons) in ...
6
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4answers
945 views

How to filter LiDAR data by scan angle?

I am looking to filter LiDAR data (.las format) by scan angle specifications (e.g. keep all points < 15). From a basic Google search, it appears that the libLAS library has the ability to filter by ...
6
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1answer
15k views

Calculating View Angle?

I am looking for the most accurate way of calculating the view angle (Azimuth, Elevation) from a reference point (my location) A to another point B. I have the Lat, Lon, and Altitude for each point. ...
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2answers
833 views

Why does the resolution decrease with increasing incidence angle in the Sentinel-1 SAR sattelite

On this link (Sentinel1 webpage for a SLC product), the resolution is written as a range from the highest corresponding to low incidence angle, to the lowest resolution corresponding to high incidence ...
5
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2answers
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How to calculate new point coordinates from distance and angle using ArcGIS SDK for iOS?

I want to calculate the coordinates of a new point. What I have: The source point coordinates, the distance (meters) and the angle For example: I want to create a point within 100 meters and 45 ...
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3answers
187 views

Are perpendicular lines still perpendicular after converting from UTM zone 15 to 16 (or between two neighboring zones)?

I want to convert a square polygon that is close to the edge of UTM zones 15N and 16N. The polygon's coordinates are in UTM 16N, but it is spatially positioned in the UTM15 area. My question is that ...
5
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1answer
126 views

Relative position of nodes

I am studying bird movements and have tracked their locations, ie from flower 1 to flower 2 to flower 3 etc. Each point is mapped out. I am trying to work out the relative direction for each movement ...
5
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1answer
563 views

Setting Data Driven Pages rotation when index has extra page polygons edited into it?

I have created an index to use with data drive pages. I used strip map index and then altered the geometry of the index polygons to better fit my project area. I also added additional index polygons. ...
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2answers
5k views

Compute Angle of line in conventional bearing using ArcGIS API for JavaScript?

I am trying to compute angle between two lines (line segment) using ESRI (ArcGIS, JS) in conventional bearing (Eg: N29'E) I am using Add Toolbar to draw a line segment where point A is a fixed point (...
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2answers
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How can I calculate the coordinates of a point on the intersection of two parallel lines with a bisecting line with pyQGIS? [closed]

I am building some sort of homemade pyQGIS-Buffer-tool as the existing flat-end-buffer-tools are not working for me ( see v.distance.buffer does not create proper buffers with flat endcaps) Therefore ...
4
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2answers
3k views

Angle at intersection point from two Lines

I would like to find the angle of two lines at their intersection point. In my opinion it is the azimuth I'm looking for, right? So I'm using Python with shapely for finding the intersection and ...
4
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3answers
814 views

How to find intersections of lines less than 45° in FME

I'm trying to identify intersections of electrical transmission lines that are less than 45° in FME. While, in theory, this doesn't seem like such a daunting task, in practice, it's proving quite ...
4
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1answer
1k views

Estimating Landsat 7 azimuth (heading)?

I am trying to understand if the Landsat 7 satellite ETM+ orbit has any significant azimuth or if it could be assumed as 0° (as it is not a pointable sensor). I searched in the web but could not find ...
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0answers
1k views

Rotate feature by angle (QGIS)

Trying to offset a line by 10 degrees, rotating around an endpoint. I've read up on the older plugins and the new Rotate Feature tool, but am having trouble. I am using QGIS 2.8.9 Wien, reinstalled ...
3
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1answer
684 views

In QGIS, how to get an angle of a polygon / get longest line in polygon and angle of that line? [duplicate]

I am using QGIS to output data to a game engine, I use polygon centroids to find center points of polygons of houses to output to the game engine for house placement - now I'd like to take it one step ...
3
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1answer
166 views

Differences in angle measurements in Web Mercator

I am trying to measure different angles on 2D map using lat/lon coordinates taken from Google Maps, and Java library JTS. I have noticed a weird thing: my measurements are always distorted, except ...
3
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1answer
384 views

Advanced Digitizing Panel angle units

I have QGIS 2.18.3 installed. I'm trying to change angle units from degrees to Gon/gradians (90 degrees = 100 Gon). I navigated to Settings--> Options --> Map Tools --> Preferred angle units, and ...
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2answers
7k views

Calculating angle between two points (according to reference point)?

I need to calculate the angles between two points on ArcGIS. I have ArcInfo License, too. I have 5 points on a diagram. One of them is my reference point. The other four creates angles between each ...
3
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1answer
312 views

Calculate shortest distance from point to polygon according angle table

I have a point in polygon. I want to have new polyline shapefile, which will show the shortest distance from the point to polygon edge, according to given angles in the table.
3
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1answer
4k views

What are the main drawbacks of the AuthaGraph projection?

The AuthaGraph projection has recently been hyped as the "perfect projection" for a world map, since it (approximately) conserves area, shape and distances. It also tessellates, so that any point can ...
3
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1answer
243 views

Calculate field of view / angle of a point to a shapefile

I am trying to automate a calculation of the blocked fraction of a field of view from a point to a shapefile. I.e. find α in , such that α / 360 gives me the fraction of the field of view covered by ...
3
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0answers
67 views

Given a line find whether another line is along side, N,E,S,W or not

I have a shapefile representing roads (Black) and I need to know whether another line object (Red) is to the side of it. Including the orientation between them, to define whether the Red line lies to ...
3
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0answers
322 views

How to digitize 90 degree angles? [duplicate]

Possible Duplicate: How to create polygons with straight lines and right angles in QGIS? In QGIS 1.8 is there a way to digitize buildings etc. with perfect 90-degree angles, Or, edit a polygon ...
2
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3answers
3k views

How to get around “The field is not nullable” error?

I have a shapefile of lines. I want the angle of every line calculated in a field. I am using the script below in arcmap, but when it encounters a line that is horizontal, it stops calculating any ...
2
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1answer
199 views

Generating new point file based on specified distances and azimuths/angles from previous point in ArcMap?

I have a shapefile of multiple points (upwards of 100). I would like to generate a new shapefile with points that are a specified distance and direction away from the previous points. For example, ...
2
votes
1answer
2k views

Find the intersection angle between two lines counter-clockwise around a circle ArcGIS 10.x

I am trying to create a tool for measuring the angle between two intersecting lines. I have created a buffer and clipped the lines to within this buffer and computed the angle between the lines using ...
2
votes
1answer
137 views

Determining the cosine of the angles between two lines using dot product

SCENARIO:I have a certain buffered region (lets say a one way road segment), which will have only one allowed direction represented by vector A. And, there are several other lines which may or may not ...
2
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2answers
1k views

Computing the elevation angle of a GPS satellite with respect to the given receiver location

can anyone source an explicit formula for calculating the elevation angle for a GPS satellite as seen from a receiver. I can't seem to find one. Even a text reference would be great. I couldn't quite ...
2
votes
1answer
106 views

Rotation symbol in ArcGIS online not always available?

I'm currently making an application with Survey123 and ArcGIS online. This application uses the survey to add ratings on 9 subjects. The added points are loaded into an webmap in ArcGIS Online which ...
2
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1answer
1k views

Point-Line shortest distance and corresponding angle using FME

I want to determine the shortest distance and especially the corresponding angle from a point to a polyline. A solution using FME would be strongly preferred.
2
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2answers
246 views

Determining angle for polyline geometries that share a point

With help I've written code to determine the angle between two line geometries. However, the code assumes each line extends into infinity and doesn't account for the shared point. Thus an angle of 150 ...
2
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0answers
338 views

How to calculate angle between two points and vertical [duplicate]

Is there an easy method to calculate angle between two points and vertical with PyQGIS ? In QGIS I use Cad-Tools extension, I select two points and it give me an azimuth. Now I would like to do the ...
2
votes
0answers
120 views

How to calculate cumulative angles on specific routes?

I am using Network Analyst extension in ArcGIS 10.4 (Windows 10 Pro 64bit) to calculate accumulative angles from Node 1 to Node 423 on the shortest path as shown in the left side of Figure 1. Network ...
2
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0answers
173 views

Radar incidence angle of different images [closed]

I am beginning in radar traitement, I want to know if working with radar image with differents incidence angle is not correct for result, Could the radar image have the same incidence angle for ...
2
votes
0answers
434 views

Rotate symbol base on polyline angle

I am using AcadMap to bring in .shp files for polylines. I have AutoCAD tickmark block at midpoint but it is at 0 degrees (straight up). Is there any way to rotate block angle to match polyline ...
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2answers
162 views

Extract vertices QGIS 3

I am using Extract vertices in QGIS 3. The table in result shows angles. What do those angles mean?
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1answer
49 views

Getting angle of point generated from DEM in Raster using Field Calculator in ArcGIS Desktop?

I am trying to calculate the angle of some specific points generated from flow direction in ArcMap 10.2. I converted the DEM to flow direction and then to points. I am trying to convert the grid_code ...
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1answer
248 views

QGIS Labels Rotation

I have imported some OS MasterMap data into QGIS 3.2 and have labelled the Cartographic Text dataset. This dataset has a rotation field, populated with various angles of rotation depending where they ...
1
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1answer
82 views

View Angle Calculation

In Calculating View Angle? the accepted answer contains the following calculations: Given two points (x,y,z) and (x',y',z') in an earth-centered coordinate system, the vector from the first to the ...
1
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2answers
2k views

Calculate actual Landsat image corner coordinates to derive azimuth (heading)

This is the continuation of an unsolved problem I had (see this thread if you like). I have a Landsat image and I would like to estimate the satellite azimuth for my location. As the satellite follows ...
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2answers
448 views

Calculate Polygon Main Angle in QGIS with Python

At the moment I have split my imported shapefile into the parts with the function 'qgis: explode' (pic1 & pic2): Next I want to the polygon main angle of each "exploded" element. In ArcGIS there ...
1
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1answer
172 views

MBG_Orientation: ranges from 0-180, instead of 0-360? (ArcGIS, Minimal Bounding Geometry)

I'm trying to understand the concept of the Orientation of the Minimal Bounding Geometry: Minimum Bounding Geometry (Data Management toolbox, ArcGIS Desktop 10.1). I run the tool Minimal Bounding ...
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2answers
66 views

Getting existing rotational value in QGIS?

I have one DXF file for and I loaded in QGIS canvas. In attribute table I did not found any angle for label. How can we know the existing angle in which the label displayed?
1
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1answer
305 views

Is there a Field Calculator or GUI based way to move points by angle and distance in QGIS?

In QGIS what is the best way of moving an existing point (or digitising a new point) when you have: the starting x,y (UTM) coordinate; the angle from compass bearing towards the unknown point, and; a ...
1
vote
1answer
264 views

Filtering LiDAR data with las2las by scan angle range?

I am using las2las to filter .las data and I would like to filter the data between a scan angle of -15:+15; however the algorithm tells me the following: ? error bad lexical cast: source type value ...