I'm writing a code to plot the circular orbit of a satellite (created using comet3() function) around a 3d model of the Earth (created using surf() and set() functions). The problem is that I can't seem to find a way to get them together in the same plot. I have tried using hold on and hold off but that doesn't seem to work either. I'm pasting the MATLAB code below for reference.
Edit: All the other functions like sv_from_coe(), odeset, etc. are working perfectly, the only place I'm facing issue is combining the plots from comet3() and set().
G = 6.67E-11;
Me = 5.976E24;
coe = [6776, 0.0005638, 2.0543, 0.9, 5.549, 0];
[r, v] = sv_from_coe(coe);
rv = [r v];
opt = odeset('RelTol', 1e-6, 'AbsTol', 1e-6);
[t,X] = ode45(#rate, [0 2*1.5*3600], rv, opt);
[x,y,z] = sphere;
r_earth = 6378*1000;
figure
hs1 = surf(x*r_earth,y*r_earth,-z*r_earth);
cdata = imread('1024px-Land_ocean_ice_2048.jpg');
alpha = 1;
hold on
axis equal
comet3(X(:,1), X(:,2), X(:,3))
set(hs1, 'FaceColor', 'texturemap', 'CData', cdata, 'FaceAlpha', alpha, 'EdgeColor', 'none')
You just have to reverse the order, first plot the earth and set the texture. Then use comet3 to animate the trajectory:
% earth
[x,y,z] = sphere;
r_earth = 6378*1000;
% some simple trajectory
phi = 0:0.01:2*pi;
r_orbit = r_earth + 408*1e3; % ISS orbit height
xv = r_orbit * cos(phi);
yv = r_orbit * sin(phi);
zv = zeros(size(yv));
% draw figure
figure(1); clf;
ax = axes;
% first plot the earth and set texture
hs1 = surf(x*r_earth,y*r_earth,-z*r_earth);
alpha = 1;
cdata = imread("Land_ocean_ice_2048.jpg");
set(hs1, 'FaceColor', 'texturemap', 'CData', cdata, 'FaceAlpha', alpha, 'EdgeColor', 'none')
hold on
axis equal
% finally, animate using comet3
comet3(xv,yv,zv)
I have the following figure, where I plotted two surfaces and I wanted to indicate the intersection of both of them. To do that, I did the following:
zdiff = z1-z2;
C = contours(x,y,zdiff,[0 0]);
xL = C(1, 2:end);
yL = C(2, 2:end);
zL = interp2(x, y, z1, xL, yL);
line(xL, yL, zL, 'Color', 'k', 'LineWidth', 2,'Linestyle','--'); hold on;
line(xL, yL, zeros(size(zL)), 'Color', 'k', 'LineWidth', 2); hold off;
Now, I want to plot the vertical surface between the actual intersection (dash line) and its projection over XY (solid line), but I cannot figure out how to do that. Any ideas?
Another really simple option:
dist = (diff(xL).^2+diff(yL).^2).^0.5; %distance between x,y
cdist = [0, cumsum(dist)]; %cumsum of the distance
area = trapz(cdist,zL); %The area
Why not calculating it manually?
Something like (untested):
Area = 0
for i=1:numel(xL)-1
base = sqrt( (xL(i)-xL(i+1))^2 + (yL(i)-yL(i+1))^2);
Area =Area + base * (zL(i) + zL(i+1))/2;
end;
maybe not pretty but its a oneliner it might do the trick. maybe you have to adjust the format as this code is for (1,N) vectors
xL=(1:100); %size 1 100
yL=(1:100) ;%size 1 100
zL=rand(1,100);%size 1 100
line(xL,yL,zL)
line(xL,yL,zeros(size(zL)))
hold on
surf(repmat(xL,100,1),repmat(yL,100,1),cell2mat(arrayfun(#(x,y) linspace(x,y,100)',zL,zeros(size(zL)),'UniformOutput',false)))
xL=sin((1:30)/10); % Data generation for test only. Use your data
yL=cos((1:30)/10); % Data generation for test only. Use your data
zL=2+xL.*yL; % Data generation for test only. Use your data
surf([xL;xL],[yL;yL],[zeros(size(zL));zL]); % plot the surface
I have 4 sets of values: y1, y2, y3, y4 and one set x. The y values are of different ranges, and I need to plot them as separate curves with separate sets of values on the y-axis.
To put it simple, I need 3 y-axes with different values (scales) for plotting on the same figure.
Any help appreciated, or tips on where to look.
This is a great chance to introduce you to the File Exchange. Though the organization of late has suffered from some very unfortunately interface design choices, it is still a great resource for pre-packaged solutions to common problems. Though many here have given you the gory details of how to achieve this (#prm!), I had a similar need a few years ago and found that addaxis worked very well. (It was a File Exchange pick of the week at one point!) It has inspired later, probably better mods. Here is some example output:
(source: mathworks.com)
I just searched for "plotyy" at File Exchange.
Though understanding what's going on in important, sometimes you just need to get things done, not do them yourself. Matlab Central is great for that.
One possibility you can try is to create 3 axes stacked one on top of the other with the 'Color' properties of the top two set to 'none' so that all the plots are visible. You would have to adjust the axes width, position, and x-axis limits so that the 3 y axes are side-by-side instead of on top of one another. You would also want to remove the x-axis tick marks and labels from 2 of the axes since they will lie on top of one another.
Here's a general implementation that computes the proper positions for the axes and offsets for the x-axis limits to keep the plots lined up properly:
%# Some sample data:
x = 0:20;
N = numel(x);
y1 = rand(1,N);
y2 = 5.*rand(1,N)+5;
y3 = 50.*rand(1,N)-50;
%# Some initial computations:
axesPosition = [110 40 200 200]; %# Axes position, in pixels
yWidth = 30; %# y axes spacing, in pixels
xLimit = [min(x) max(x)]; %# Range of x values
xOffset = -yWidth*diff(xLimit)/axesPosition(3);
%# Create the figure and axes:
figure('Units','pixels','Position',[200 200 330 260]);
h1 = axes('Units','pixels','Position',axesPosition,...
'Color','w','XColor','k','YColor','r',...
'XLim',xLimit,'YLim',[0 1],'NextPlot','add');
h2 = axes('Units','pixels','Position',axesPosition+yWidth.*[-1 0 1 0],...
'Color','none','XColor','k','YColor','m',...
'XLim',xLimit+[xOffset 0],'YLim',[0 10],...
'XTick',[],'XTickLabel',[],'NextPlot','add');
h3 = axes('Units','pixels','Position',axesPosition+yWidth.*[-2 0 2 0],...
'Color','none','XColor','k','YColor','b',...
'XLim',xLimit+[2*xOffset 0],'YLim',[-50 50],...
'XTick',[],'XTickLabel',[],'NextPlot','add');
xlabel(h1,'time');
ylabel(h3,'values');
%# Plot the data:
plot(h1,x,y1,'r');
plot(h2,x,y2,'m');
plot(h3,x,y3,'b');
and here's the resulting figure:
I know of plotyy that allows you to have two y-axes, but no "plotyyy"!
Perhaps you can normalize the y values to have the same scale (min/max normalization, zscore standardization, etc..), then you can just easily plot them using normal plot, hold sequence.
Here's an example:
%# random data
x=1:20;
y = [randn(20,1)*1 + 0 , randn(20,1)*5 + 10 , randn(20,1)*0.3 + 50];
%# plotyy
plotyy(x,y(:,1), x,y(:,3))
%# orginial
figure
subplot(221), plot(x,y(:,1), x,y(:,2), x,y(:,3))
title('original'), legend({'y1' 'y2' 'y3'})
%# normalize: (y-min)/(max-min) ==> [0,1]
yy = bsxfun(#times, bsxfun(#minus,y,min(y)), 1./range(y));
subplot(222), plot(x,yy(:,1), x,yy(:,2), x,yy(:,3))
title('minmax')
%# standarize: (y - mean) / std ==> N(0,1)
yy = zscore(y);
subplot(223), plot(x,yy(:,1), x,yy(:,2), x,yy(:,3))
title('zscore')
%# softmax normalization with logistic sigmoid ==> [0,1]
yy = 1 ./ ( 1 + exp( -zscore(y) ) );
subplot(224), plot(x,yy(:,1), x,yy(:,2), x,yy(:,3))
title('softmax')
Multi-scale plots are rare to find beyond two axes... Luckily in Matlab it is possible, but you have to fully overlap axes and play with tickmarks so as not to hide info.
Below is a nice working sample. I hope this is what you are looking for (although colors could be much nicer)!
close all
clear all
display('Generating data');
x = 0:10;
y1 = rand(1,11);
y2 = 10.*rand(1,11);
y3 = 100.*rand(1,11);
y4 = 100.*rand(1,11);
display('Plotting');
figure;
ax1 = gca;
get(ax1,'Position')
set(ax1,'XColor','k',...
'YColor','b',...
'YLim',[0,1],...
'YTick',[0, 0.2, 0.4, 0.6, 0.8, 1.0]);
line(x, y1, 'Color', 'b', 'LineStyle', '-', 'Marker', '.', 'Parent', ax1)
ax2 = axes('Position',get(ax1,'Position'),...
'XAxisLocation','bottom',...
'YAxisLocation','left',...
'Color','none',...
'XColor','k',...
'YColor','r',...
'YLim',[0,10],...
'YTick',[1, 3, 5, 7, 9],...
'XTick',[],'XTickLabel',[]);
line(x, y2, 'Color', 'r', 'LineStyle', '-', 'Marker', '.', 'Parent', ax2)
ax3 = axes('Position',get(ax1,'Position'),...
'XAxisLocation','bottom',...
'YAxisLocation','right',...
'Color','none',...
'XColor','k',...
'YColor','g',...
'YLim',[0,100],...
'YTick',[0, 20, 40, 60, 80, 100],...
'XTick',[],'XTickLabel',[]);
line(x, y3, 'Color', 'g', 'LineStyle', '-', 'Marker', '.', 'Parent', ax3)
ax4 = axes('Position',get(ax1,'Position'),...
'XAxisLocation','bottom',...
'YAxisLocation','right',...
'Color','none',...
'XColor','k',...
'YColor','c',...
'YLim',[0,100],...
'YTick',[10, 30, 50, 70, 90],...
'XTick',[],'XTickLabel',[]);
line(x, y4, 'Color', 'c', 'LineStyle', '-', 'Marker', '.', 'Parent', ax4)
(source: pablorodriguez.info)
PLOTYY allows two different y-axes. Or you might look into LayerPlot from the File Exchange. I guess I should ask if you've considered using HOLD or just rescaling the data and using regular old plot?
OLD, not what the OP was looking for:
SUBPLOT allows you to break a figure window into multiple axes. Then if you want to have only one x-axis showing, or some other customization, you can manipulate each axis independently.
In your case there are 3 extra y axis (4 in total) and the best code that could be used to achieve what you want and deal with other cases is illustrated above:
clear
clc
x = linspace(0,1,10);
N = numel(x);
y = rand(1,N);
y_extra_1 = 5.*rand(1,N)+5;
y_extra_2 = 50.*rand(1,N)+20;
Y = [y;y_extra_1;y_extra_2];
xLimit = [min(x) max(x)];
xWidth = xLimit(2)-xLimit(1);
numberOfExtraPlots = 2;
a = 0.05;
N_ = numberOfExtraPlots+1;
for i=1:N_
L=1-(numberOfExtraPlots*a)-0.2;
axesPosition = [(0.1+(numberOfExtraPlots*a)) 0.1 L 0.8];
if(i==1)
color = [rand(1),rand(1),rand(1)];
figure('Units','pixels','Position',[200 200 1200 600])
axes('Units','normalized','Position',axesPosition,...
'Color','w','XColor','k','YColor',color,...
'XLim',xLimit,'YLim',[min(Y(i,:)) max(Y(i,:))],...
'NextPlot','add');
plot(x,Y(i,:),'Color',color);
xlabel('Time (s)');
ylab = strcat('Values of dataset 0',num2str(i));
ylabel(ylab)
numberOfExtraPlots = numberOfExtraPlots - 1;
else
color = [rand(1),rand(1),rand(1)];
axes('Units','normalized','Position',axesPosition,...
'Color','none','XColor','k','YColor',color,...
'XLim',xLimit,'YLim',[min(Y(i,:)) max(Y(i,:))],...
'XTick',[],'XTickLabel',[],'NextPlot','add');
V = (xWidth*a*(i-1))/L;
b=xLimit+[V 0];
x_=linspace(b(1),b(2),10);
plot(x_,Y(i,:),'Color',color);
ylab = strcat('Values of dataset 0',num2str(i));
ylabel(ylab)
numberOfExtraPlots = numberOfExtraPlots - 1;
end
end
The code above will produce something like this:
I am trying to write some code to generate a plot similar to the one below on matlab (taken from here):
I have a set of points on a curve (x_i,y_i,z_i). Each point generates a Gaussian distribution (of mean (x_i,y_i,z_i) and covariance matrix I_3).
What I did is I meshed the space into npoint x npoints x npoints and computed the sum of the probability densities for each of the 'sources' (x_i,y_i,z_i) in each point (x,y,z). Then, if the value I get is big enough (say 95% of the maximum density), I keep the point. otherwise I discard it.
The problem with my code is that it is too slow (many for loops) and the graph I get doesn't look like the one below:
Does anyone know whether there is a package to get a similar plot as the one below?
Using isosurface we can do reasonably well. (Although I'm not honestly sure what you want, I think this is close:
% Create a path
points = zeros(10,3);
for ii = 2:10
points(ii, :) = points(ii-1,:) + [0.8 0.04 0] + 0.5 * randn(1,3);
end
% Create the box we're interested in
x = linspace(-10,10);
y = x;
z = x;
[X,Y,Z] = meshgrid(x,y,z);
% Calculate the sum of the probability densities(ish)
V = zeros(size(X));
for ii = 1:10
V = V + 1/(2*pi)^(3/2) * exp(-0.5 * (((X-points(ii,1)).^2 + (Y-points(ii,2)).^2 + (Z-points(ii,3)).^2)));
end
fv = isosurface(X,Y,Z,V, 1e-4 * 1/(2*pi)^(3/2), 'noshare');
fv2 = isosurface(X,Y,Z,V, 1e-5 * 1/(2*pi)^(3/2), 'noshare');
p = patch('vertices', fv.vertices, 'faces', fv.faces);
set(p,'facecolor', 'none', 'edgecolor', 'blue', 'FaceAlpha', 0.05)
hold on;
p2 = patch('vertices', fv2.vertices, 'faces', fv2.faces);
set(p2,'facecolor', 'none', 'edgecolor', 'red', 'FaceAlpha', 0.1)
scatter3(points(:,1), points(:,2), points(:,3));