I want to plot current data (direction and magnitude) as vectors in a single plot
31 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Hi! I'm trying to plot a timeseries of current data in away that I have seen wind velocity data displayed like in the example attached. I have current direction (dir_adp3_mx) and magnitude (mag_adp3_mx) and my timestamps (MX). Can I use this data to make a plot of current velocity like the plot of wind speeds below? I think I need to use the quiver or feather functions but I am confused on how to make the X axis time in either case. Please help if you have ideas. I attached the data I am working with as data.mat.
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/391893/image.png)
0 Kommentare
Antworten (1)
Mathieu NOE
am 26 Okt. 2020
hello Heidi
below some code with quiver vs feather display. depneds of your preferences - seem I got better angular rendering with quiver.
also note that I have dispayed only the first 100 samples to get a better picture to show the differences in rendering
I have manually added a baseline to the standard quiver display - so at the end it's very similar to what feather do;
you can of course remove that
hope it helps
Mathieu
load data.mat
% data file content :
% Name Size Bytes Class Attributes
%
% MX 4888x1 39104 double
% dir_adp3_mx 4888x1 39104 double
% mag_adp3_mx 4888x1 39104 double
% quiver(X,Y,U,V) plots velocity vectors as arrows with components (u,v)
% at the points (x,y). The matrices X,Y,U,V must all be the same size
% and contain corresponding position and velocity components (X and Y
% can also be vectors to specify a uniform grid). quiver automatically
% scales the arrows to fit within the grid.
% we need to create the X and Y coordinates of each vector
% NB : current direction (dir_adp3_mx) is in degrees
direction_rad = pi/180*dir_adp3_mx;
Xvec= mag_adp3_mx.*cos(direction_rad);
Yvec= mag_adp3_mx.*sin(direction_rad);
% create x,y points for quiver % quiver(X,Y,U,V) plots velocity vectors
% as arrows with components (u,v) at the points (x,y).
time = MX-MX(1); % so x start at 0 (needed ?)
y = zeros(size(x)); % base line
samples = 100; % to remove if necessary
%
figure(1)
quiver(time(1:samples),y(1:samples),Xvec(1:samples),Yvec(1:samples),'.');
% add central line
hold on
plot(time(1:samples),y(1:samples));
hold off
% quiver(...,LINESPEC) uses the plot linestyle specified for
% the velocity vectors. Any marker in LINESPEC is drawn at the base
% instead of an arrow on the tip. Use a marker of '.' to specify
% no marker at all. See PLOT for other possibilities.
figure(2)
feather(Xvec(1:samples),Yvec(1:samples))
0 Kommentare
Siehe auch
Kategorien
Mehr zu Vector Fields finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!