0 个投票

Can I automatically find True north-based azimuths based on certain value of an azimuth from a refference point ?
Let's say if I have a value of 90 the result will be East, I have a value of 25 the result will be North-northeast.
I could do a function but maybe there's more easier methodes.
Thank you!

请先登录，再回答此问题。

 采纳的回答

Bjorn Gustavsson
Bjorn Gustavsson 2022-5-22

0 个投票

Your question doesn't make much sense, sure you can do that - but that would be more of "establishing" your azimuth-convention. If you are thinking of calculating the azimuth clockwise from North to a point [x,y] from a point [x0,y0]. Then atan2 should be your friend:
phi = atan2(x0-x,y0-y);
Or atan2d if you directly want the angle in degrees - which I've found to be a dangerous habit to use, it is in my experience strongly preferable to have all angles in radians and convert to degrees when displaying.
HTH

5 个评论
显示 3更早的评论 隐藏 3更早的评论

Cristian Martin
Cristian Martin 2022-5-22
Bjorn, I mean Cardinal points, sorry. Based of an specified azimuth. If the az=90 result be East.
Bjorn Gustavsson
Bjorn Gustavsson 2022-5-22
What is your problem? Do you want to convert a set of azimuth-angles relative to some cardinal direction to an azimuth clockwise from north?
Cristian Martin
Cristian Martin 2022-5-22
I think my question was not so clear, excuse me.
Let's say I have:
Coord 1:
lat1 = value 1 in dm;
lon1 = value 2 in dm;
Coord 2:
lat2 = value 3 in dm;
lon2 = value 4 in dm;
The azimut from coord 1 to coord 2 is 45 degree. Matlab has a command for displaying cardinal point in this case Northeast ?
I have found something but I don't know how to adapt it in my case
directionValues = 0:22.5:337.5;
directionNames = {'N','NNE','NE','ENE','E','ESE','SE','SSE','S','SSV','SV','VSV','V','VNV','NV','NNV'};
directionValues(strcmp(directionNames,'V'));
Bjorn Gustavsson
Bjorn Gustavsson 2022-5-22
If you want to display the label from directionNames with the directionValues closest to an arbitrary angle, phi, you only have to determine the "best matching direction". You can for example do this:
dl2 = ((cosd(phi)-cosd(directionValues)).^2 + ...
(sind(phi)-sind(directionValues)).^2); % should be robust to wrap-arounds
[dl,idx_best] = min(dl2);
disp(directionNames);
HTH

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Lengths and Angles 的更多信息

产品

版本

R2015a

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by