I am a bit struggling with my polar plot. I am playing with strikes and dips, and for each pair of those, an "intensity". I'd like to plot this surface/contourf/whatever function on my polarplot. I cannot find the handle to do so. Dpp2 contains the intensity value for a given theta and rho/ strike and dip.
xTmp = (0:4:360);
yTmp = (0:22.5:90);
[strike,dip]= meshgrid(deg2rad(xTmp),deg2rad(yTmp));
dip2 = rad2deg(dip);
strike2 =rad2deg(strike);
figure('name', 'COLD');
polarplot([0 360],[0 90]);
s = surf(strike2, dip2, DPp2);
polarplot(s);
colormap
I've tried something like that, which obviously doesn't work.
cheers,
Flo
As far as I know there is no way of creating a surface plot directly in a polarplot.
One workaround is to manually create your polar axis plot. You can find an example here.
Another workaround would be to use
polarscatter to create a scatter plot (which looks simmilar in case you have a tight grid) Have a look at this.
Because you mentioned the handle: In case you want a handle to the axes have a look at polaraxes from here.
The polar scatter wasn't working, so I tried another function, which seems to work according to this page: https://fr.mathworks.com/matlabcentral/answers/95796-how-do-i-create-a-contour-plot-in-polar-coordinates
I am note quite there yet, the contour map isn't "wrapped" around my polar plot, but so far it's compiling. If anyone has an idea on how to superimpose the contour map onto the polar plot ?
dip2 = rad2deg(dip);
strike2 =rad2deg(strike);
h = polar([0 360],[0 90]);
hold on;
contourf(strike2,dip2,DPp2);
% Hide the POLAR function data and leave annotations
set(h,'Visible','off')
% Turn off axes and set square aspect ratio
axis off
axis image
Related
I would like to be able to overlay isolines over a filled contour or surface as it is done in this figure:
Can matlab overlay contour and contourf plots?
So far, I have tried this:
[X,Y] = meshgrid(x_cases,y_cases);
Points = length(x_cases)*length(y_cases);
resX = reshape(X,Points,1);
resY = reshape(Y,Points,1);
resZ = reshape(DataGrid_a,Points,1);
scatter(resX,resY,[],resZ,’filled’)
hold on
contour(X,Y,DataGrid_b,'ShowText','on')
But I have to reduce the transparency of my scatter plot to be able to see the contour lines from DataGrid_b, it would be more ideal to not change the transparency and overlay my isolines. I appreciate any input you may give me!
Thanks!
The simplest solution (and it's very hack) is to take advantage of the fact that 2D plots are plotted at Z = 0; So put your scatter points at some Z value below that.
scatter3(resX,resY,-ones(size(resX)),[],resZ,’filled’)
view(2)
hold on
contour(X,Y,DataGrid_b,'ShowText','on')
I have 3D cloud of dots. I need to plot them as a surface. I tried variant with meshdrid, griddata, scatteredInterpolant,trisurf-delaunay. Nothing works. I know that this question was discussed a lot, but it seems I don't understand some important details. The code which i have now:
load('coords.mat')
figure()
subplot(1,2,1)
plot3(x,y,z,'.')
axis off
view(3)
subplot(1,2,2)
C=gray(numel(x)); % unsuccessful attempt
[~,idx]=sort(z); % to have
C=C(idx,:); % illumination
scatter3(x,y,z,50,C,'filled')
axis off
view(3)
produces the following image:
Could you help me:
1) to find a way to draw it with surface function.
and as some dots may be inside the surface (may be it is my problem)
2) How to remove 'invisible' dots?
I need solution for different cases, picture and data presents just an example.
Mat file may be downloaded here.
P.S.
In case it is important – I obtain coordinates of this dots as a rotation of random bezier curve.
UPDATE
In case data above is too big I generate another set with smaller amount of dots:
Coordinates are here.
where do you get this data from? It is represented as vectors but if you reshape it to matrices you can use the surf function. Try this code:
z=reshape(z,100,100);
y=reshape(y,100,100);
x=reshape(x,100,100);
surf(x,y,z)
I am currently trying to plot 3D streamtubes. I want the tubes to be colored corresponding to their respective velocity (e.g. slow = blue, fast = red).
To be more exact, I have three 3D-matrices containing the velocity in x, y and z direction. The color of the streamtubes should be sqrt(vx^2+vy^2+vz^2). When using streamtube(x,y,z,vx,vy,vz,sx,sy,sz) the tubes are colored according to their z-coordinate which is useless because it's a 3D plot anyway.
Well this wasn't easy (it ought to be a builtin option), but by modifying the CData of each tube (they are each their own graphics object), you can achieve the desired result. Here's an example
load wind
[sx,sy,sz] = meshgrid(80,20:10:50,0:5:15);
h=streamtube(x,y,z,u,v,w,sx,sy,sz);
drawnow
view(3)
axis tight
shading interp;
This gives this picture:
but then doing this:
vel=sqrt(u.^2+v.^2+w.^2); %// calculate velocities
for i=1:length(h)
%// Modify the colour data of each tube
set(h(i),'CData',interp3(x,y,z,vel,get(h(i),'XData')...
,get(h(i),'YData'),get(h(i),'ZData'),'spline'))
end
drawnow
view(3)
axis tight
shading interp;
gives this result
NOTES:
1) I don't know if this is fully correct, I don't know how to test it
2) You have to interpolate the velocity data from the points where it's known onto the vertices of the streamtubes
3) I found the spline interpolation option to work best, but the other options might work better in other cases
I know this question has been asked before - but none of them deal with a 3D plot with 2 Y axis. My question is a continuation of - How do I add a 2D Plot along with a surface or mesh plot in MATLAB? or this.
I have now successfully managed to add a 2D plot along with a surface plot. See image below -
Now my problem is that the range of the 2D plot is so high that the 3D plot is shrunk to look like nothing more than a plane on the ceiling. It is supposed to have variations like the figure in the question I have lined above.
How do I provide a different Y axis for the 2D plot so that the 3D plot is not shrunk like it is here.
It's possible that you can use the DataAspectRatio property to accomplish this. Taking inspiration from the example from the previous post, if we have:
z=peaks(100);
x1=linspace(0,100);
plot3(x1,0*ones(1,numel(x1)),40*sin(x1))
surface(z+40, 'edgecolor', 'none');
and then you can use
set( gca, 'dataaspectratio', [1.25 1.25 .7] )
view( [-37.5 18] )
can work in some cases to help regain some of the range on the surface plot. This method won't work, however, in very extreme cases.
I'm using polar plots (POLAR(THETA,RHO)) in MATLAB.
Is there an easy way to fix the range for the radial axis to say, 1.5?
I'm looking for something analogous to the xlim, ylim commands for cartesian axes. Haven't found anything in the docs yet.
this worked for me... i wanted the radius range to go to 30, so i first plotted this
polar(0,30,'-k')
hold on
and then plotted what i was actually interested in. this first plotted point is hidden behind the grid marks. just make sure to include
hold off
after your final plotting command.
Here's how I was able to do it.
The MATLAB polar plot (if you look at the Handle Graphics options available) does not have anything like xlim or ylim. However, I realized that the first thing plotted sets the range, so I was able to plot a function with radius range [-.5 .5] on a [-1 1] plot as follows:
theta = linspace(0,2*pi,100);
r = sin(2*theta) .* cos(2*theta);
r_max = 1;
h_fake = polar(theta,r_max*ones(size(theta)));
hold on;
h = polar(theta, r);
set(h_fake, 'Visible', 'Off');
That doesn't look very good and hopefully there's a better way to do it, but it works.
Simple solution is to make a fake graph and set its color to white.
fake=100;
polar(0,fake,'w');
hold on;
real=10;
polar(0,real,'w');
In case anyone else comes across this, here's the solution:
As Scottie T and gnovice pointed out, Matlab basically uses the polar function as an interface for standard plots, but with alot of formatting behind the scenes to make it look polar. Look at the values of the XLim and YLim properties of a polar plot and you'll notice that they are literally the x and y limits of your plot in Cartesian coordinates. So, to set a radius limit, use xlim and ylim, or axis, and be smart about the values you set:
rlim = 10;
axis([-1 1 -1 1]*rlim);
...that's all there is to it. Happy Matlabbing :)