Mathematically, the relative position vector from an observer (origin) to a point of interest is projected perpendicularly onto a reference plane (the horizontal plane); the angle between the projected vector and a reference vector on the reference plane is called the azimuth.
When used as a celestial coordinate, the azimuth is the horizontal direction of a star or other astronomical object in the sky. The star is the point of interest, the reference plane is the local area (e.g. a circular area with a 5 km radius at sea level) around an observer on Earth's surface, and the reference vector points to true north. The azimuth is the angle between the north vector and the star's vector on the horizontal plane.[2]
Azimuth Angle
Download File š„ https://tlniurl.com/2yGAsl š„
The word azimuth is used in all European languages today. It originates from medieval ArabicĀ (al-sumt, pronounced as-sumt), meaning "the directions" (plural of ArabicĀ al-samt = "the direction"). The Arabic word entered late medieval Latin in an astronomy context and in particular in the use of the Arabic version of the astrolabe astronomy instrument. Its first recorded use in English is in the 1390s in Geoffrey Chaucer's Treatise on the Astrolabe. The first known record in any Western language is in Spanish in the 1270s in an astronomy book that was largely derived from Arabic sources, the Libros del saber de astronoma commissioned by King Alfonso X of Castile.[3]
In the horizontal coordinate system, used in celestial navigation, azimuth is one of the two coordinates.[4] The other is altitude, sometimes called elevation above the horizon. It is also used for satellite dish installation (see also: sat finder).In modern astronomy azimuth is nearly always measured from the north.
In land navigation, azimuth is usually denoted alpha, tag_hash_116, and defined as a horizontal angle measured clockwise from a north base line or meridian.[5][6] Azimuth has also been more generally defined as a horizontal angle measured clockwise from any fixed reference plane or easily established base direction line.[7][8][9]
Today, the reference plane for an azimuth is typically true north, measured as a 0 azimuth, though other angular units (grad, mil) can be used. Moving clockwise on a 360 degree circle, east has azimuth 90, south 180, and west 270. There are exceptions: some navigation systems use south as the reference vector. Any direction can be the reference vector, as long as it is clearly defined.
Quite commonly, azimuths or compass bearings are stated in a system in which either north or south can be the zero, and the angle may be measured clockwise or anticlockwise from the zero. For example, a bearing might be described as "(from) south, (turn) thirty degrees (toward the) east" (the words in brackets are usually omitted), abbreviated "S30E", which is the bearing 30 degrees in the eastward direction from south, i.e. the bearing 150 degrees clockwise from north. The reference direction, stated first, is always north or south, and the turning direction, stated last, is east or west. The directions are chosen so that the angle, stated between them, is positive, between zero and 90 degrees. If the bearing happens to be exactly in the direction of one of the cardinal points, a different notation, e.g. "due east", is used instead.
A better approximation assumes the Earth is a slightly-squashed sphere (an oblate spheroid); azimuth then has at least two very slightly different meanings. Normal-section azimuth is the angle measured at our viewpoint by a theodolite whose axis is perpendicular to the surface of the spheroid; geodetic azimuth (or geodesic azimuth) is the angle between north and the ellipsoidal geodesic (the shortest path on the surface of the spheroid from our viewpoint to Point 2). The difference is usually negligible: less than 0.03 arc second for distances less than 100 km.[10]
To calculate the azimuth of the Sun or a star given its declination and hour angle at a specific location, modify the formula for a spherical Earth. Replace tag_hash_1212 with declination and longitude difference with hour angle, and change the sign (since the hour angle is positive westward instead of east).[citation needed]
Remark that the reference axes are swapped relative to the (counterclockwise) mathematical polar coordinate system and that the azimuth is clockwise relative to the north.This is the reason why the X and Y axis in the above formula are swapped.If the azimuth becomes negative, one can always add 360.
There is a wide variety of azimuthal map projections. They all have the property that directions (the azimuths) from a central point are preserved. Some navigation systems use south as the reference plane. However, any direction can serve as the plane of reference, as long as it is clearly defined for everyone using that system.
If, instead of measuring from and along the horizon, the angles are measured from and along the celestial equator, the angles are called right ascension if referenced to the Vernal Equinox, or hour angle if referenced to the celestial meridian.
In mathematics, the azimuth angle of a point in cylindrical coordinates or spherical coordinates is the anticlockwise angle between the positive x-axis and the projection of the vector onto the xy-plane. A special case of an azimuth angle is the angle in polar coordinates of the component of the vector in the xy-plane, although this angle is normally measured in radians rather than degrees and denoted by tag_hash_126 rather than tag_hash_127.
In sound localization experiments and literature, the azimuth refers to the angle the sound source makes compared to the imaginary straight line that is drawn from within the head through the area between the eyes.
Why are azimuth and elevation so important for us... the PhotoPillers? The answer is simple: because we will need to calculate and set them to take advantage of the Find option of the Planner to plan our ideal sun and moon shots in just seconds.
The best way to learn how to calculate and set the azimuth and the elevation you need is by having a look at a few real examples. The following video tutorials will teach you how to do it for different situations, step-by-step:
In conclusion, mastering azimuth and elevation will give you the power to plan any photo you imagine with sun and moon, including: a full moon setting under a secret stone arch, a sunrise between two giant rocks located on a magic beach, a sunset over the main street in your hometown or a dramatic full moon appearing from behind a nearby hill...
The azimuth angle is the compass direction from which the sunlight is coming. At solar noon, the sun is always directly south in the northern hemisphere and directly north in the southern hemisphere. The azimuth angle varies throughout the day as shown in the animation below. At the equinoxes, the sun rises directly east and sets directly west regardless of the latitude, thus making the azimuth angles 90 at sunrise and 270 at sunset. In general however, the azimuth angle varies with the latitude and time of year and the full equations to calculate the sun's position throughout the day are given on the following page.
I would like to know if there is currently any way to have the value in degrees of azimuth and incidence angle. I have tried everything they have written on similar topics, but I cannot solve it (even in metadata).
Sorry for not indicating it and thanks for your reply. At the moment, with Sentinel 1. what happens is that I review in metadata but the value of these (in degrees) is not indicated. The incidence angle (near / far) indicates 999999 and I do not know which to use, if the near or far in the case of having a correct figure. On the other hand, the azimuth angle is not indicated anywhere.
Thank you very much for your reply! Yes, I have tried to do that but I think it is an image problem. For the other question about the incidence angle, do you know where I can get that data in degrees?
I have checked these topics. I only get the look direction with a cyan arrow overlaid on the image by the step of adding the mapping tools layer in SNAP. But I want to get the azimuth angle for every cell of S1. I cannot find any method to get a quantitative value for every cell of the image.
I think you search something like platform heading (Satellite azimuth heading angle for ERS) or azimuth heading (Satellite azimuth heading angle for ERS and Heading and azimuth angle).
Based on these discussions, it is constant for all pixels in an image.
There is a component in LB Tilt And Orientation Factor which output this PVsurface Azimuth PVsurfaceAzimuth Orientation angle of the inputted PV_SWHsurface. In degrees ().
Here is the image of geometry (IMAGE2). I have deconstructed it, and then I calculate the surface area. In the list (list of surface area in image1) I get surface area for all the surfaces in different direction including the floor and roof which are 1463.67) The main problem is I need to sort it according to orientation. like for example there area two surfaces facing south (azimuth angle = 180). In the shown list they area (280.2 and 105.2 have azimuth 180 and are facing south)
In short my input will be surfaces (DeBrep as seen in image1) and my output needs to be the azimuth angle.
I hope this clears my problem.
Geometry_feature_extraction.gh (29.6 KB)
This is the Gh file.
I need to record this data for further analysis. and I run this in a loop for multiple breps, hence I need a continent way to store this info.
This is really ugly to my eye but it works. Each branch of the outputs (East, West, North, South, Top and Bottom) corresponds to a separate building. It should handle a list of many buildings, not just four.
Thank you so much for all your extra effort to clean up the workflow but the First workflow you posted perfectly worked for my previous workflow. I can now record surface area with all orientation. I have a code that clears the window every time the data is changed, so every time it iterates over a new building, the previous model is eradicated. So the first workflow worked perfectly. image1832258 13.3 KB 152ee80cbc