I would like to scatter plot different sets of data points. Each point should have a different markerfacecolor, but within a given set, they would all have the same markeredgecolor.
I got this to work by looping over single scatter points individually, because markerfacecolor seems to only be able to take scalar points. The way I do it is that I loop through my data, and look for the appropriate color.
This works fine because I can define each point separately, but it becomes a problem when trying to set up the legend. It tries to list all the different points, but what I'd like is just an empty circle (markerfacecolor white or transparent), with each set having their specific markeredgecolor.
I hope this is clear enough. Thank you.
Mike
I've had luck using patches, setting 'FaceColor', 'EdgeColor' to 'none', 'MarkerEdgeColor' to 'flat' and setting the 'FaceVertexCData' to a Nx3 matrix where each row is a color corresponding the the points specified by you Nx1 'XData', 'YData' and 'ZData'.
h = patch('parent',gca,...
'XData',x,...
'YData',y,...
'ZData',z,...
'FaceColor','none',...
'EdgeColor','none',...
'MarkerFaceColor',faceColor,...
'MarkerEdgeColor','flat',... This is what sets the Edge of each marker
'FaceVertexCData',C) % C is a Nx3
I don't have access to Matlab at the moment, and Octave does not seem to have exactly the same functionality. Check out the Matlab patch properties documentation for more information.
Related
I want to plot a text file with 4 columns that first column in longitude,second in latitude, third is depth and forth is amount of displacement in each point.(it's related to a fualt)
-114.903874 41.207504 1.446784 2.323745
I want a plot to show the amount of displacement in each point (like images that we plot with imagesc),unfortunately "imagesc" command doesn't work for it.
how can I plot it?
Thanks for your attention
A simple way would be to use scatter3 and assign your displacements to be the colours. Note that you have to supply a size for this to work - I'm using [] (empty matrix) which will set it to default. If your four sets of values are four vectors of the same size, then it's just something like:
scatter3(lat,lon,depth,[],displacement, 'filled')
Values in displacement will be linearly mapped to the current colormap. 'filled' gives you filled markers rather than open ones (default marker is a circle but can be changed).
You can plot each point using plot3(longitude,latitude,depth). You can color each point according to the displacement in a for loop. The easiest way to do this is create a colormap, e.g. using jet and chosing the color according to the displacement.
figure;
hold on;
cmap = jet(256);
dispRange = [min(displacement),max(displacement)];
for k=1:size(longitude,2)
c = cmap(1+round(size(cmap,1)*(displacement(k)-dispRange(1))/dispRange(2)),:);
plot3(longitude(k),latitude(k),depth(k),'o', ...
'MarkerEdgeColor',c,'MarkerFaceColor',c);
end
I am trying to make a simple plot (for this example doing a plot of y=x^2 will suffice) where I want to set the colors of the points based on their magnitude given some colormap.
Following along my simple example say I had:
x = 1:10;
y = x.^2;
Use gscatter(x,y,jet(10)); legend hide; colorbar which produces a plot with the points colored but the colorbar does not agree with the colored values. (Can't post picture as this is my first post). Using a caxis([1,100]) command gives the right range but the colors are still off.
So I have two questions:
(1) How can I fix the colors to fit to a colorbar given a range? In my real data, I am looking at values that range from -50 to 50 in some instances and have many more data points.
(2) I want to create a different plot with the same points (but on different axes) and I want the colors of each point on this new plot to have the same colors as their counterparts in the previous plot. How can I, programmatically, extract the color from each point so I can plot it on two different sets of axes?
I would just move the points into a matrix and do an imagesc() command but they aren't spaced as integers or equally so simple scaling wouldn't work either.
Thanks for any help!
Regarding you first question, you need to interpolate the y values into a linear index to the colormap. Something like:
x = 1:10;
y = x.^4;
csize = 128;
cmap = jet(csize);
ind = interp1(linspace(min(y),max(y),csize),1:csize,y,'nearest');
scatter(x,y,14,cmap(ind,:),'filled')
colorbar
caxis([min(y) max(y)])
Using interp1 in this case is an overkill; you could calculate it directly. However, I think in this way it is clearer.
I think it also answers your 2nd question, since you have the index of the color of each data point, so you can use it again in the same way.
I'm making my own Shakemap (so far, Shamemap) with Matlab. A Shakemap is a representation of the intensity of ground shaking in a map (google it up for more info). I want it to be similar to those from the USGS, in which they plot the intensity using a jet colormap and they control the shading to represent the altimetry data. So far I haven't figured out how they do this.
I have a set of coordinates with the location's elevation (from NASA's SRTM) and in the same set of coordinates I have some parameters of ground shaking.
[lat long SRTM]
[lat long GroundShaking]
I can contour them separately, but if I put them in the same figure just like that one overrides the other.
How can I put them in the same figure? I have thought about assigning a new value to each location such that the new value accounts for both measures; locations with the same GroundShaking parameter should be the same color, but if one is higher then that one should be darker. Unfortunately I don't know how to implement this. I have also thought about setting the alpha feature manualy, but I can't make it work only for the Ground Shaking data. Any suggestions ?
MWE:
x=0:0.01:1;
y=0:0.01:1;
[xx,yy]=meshgrid(x,y);
asd1=zeros(length(x),length(y));
ads2=asd1;
for i=1:length(x)
for j=1:length(y)
asd1(i,j)=x(i)*y(j);
asd2(i,j)=x(i)*x(i)+y(j)*y(j);
end
end
c1=griddata(x,y,asd1,xx,yy, 'linear');
c2=griddata(x,y,asd2,xx,yy, 'linear');
contourf(asd1)
contourf(asd2)
alpha(0.5)
(MWE unrelated to the map because the data is huge)
You need to add a hold on so that the first plot is not overwritten. This nearly works.
colormap gray
map1=colormap
colormap jet
map2=colormap
M=[map1;map2];
asd2=asd2*(max(asd1(:))-min(asd1(:)))/(max(asd2(:))-min(asd2(:)));
asd2=asd2-max(asd2(:));
colormap(M)
caxis([min(asd2(:)) max(asd1(:))])
figure(1)
contourf(asd1)
figure(2)
contourf(asd2)
I'm plotting two pcolors on top of each other (using the m_map algorithm m_pcolor). The reason for this is that the second pcolor has transparency in it, and so shows the pcolor underneath. The first plot consists of just ones and zeroes, and I would like it to be just black and white. I would like the second to use the colormap jet, but I can't work out how to set one colormap without changing the other. My code at the moment is:
h1 = m_pcolor(Lon', Lat', black_background);
hold on;
h = m_pcolor(Lon', Lat', input_matrix);
Thanks in advance,
Adam
For this limited application, the easiest way is probably to append a row of zeros onto the colormap, deal with scaling (the clim property) yourself so that each plot takes advantage of the appropriate part of the colormap.
cm=colormap('jet'); %# Nx3
cm = [cm; 0 0 0]; %# append black row: (N+1)x3
h1 = m_pcolor(Lon',Lat',black_background);
set(h1,'clim',[length(colormap),length(colormap)])
hold on
h2 = m_pcolor(Lon', Lat', input_matrix);
set(h2,'clim',[length(colormap)-1, length(colormap)-1])
This should get you close, but I haven't tested it since I'm not on my matlab machine.
Another option is freezeColors from the file exchange (but this may only work for different axes within the same figure window, I'm not sure about different plots in the same axes object).
I have a 2D space in which a function value is defined (you can think of it as a manifold). Now I plotted the function value using contourf and changed the colormap to something softer than jet. So far it looks quite good.
Now I want to draw a line representing the state over time in my space. That is also possible using the the plot command. But I want some more improvements: There is an additional state that is hidden for now (value 0...50). I would like the line color to change according to this hidden state. So in a sense to apply a separate colormap to the line plotted by plot like for example in a waterfall plot.
Is this (or something similar) possible using matlab?
Thanks
If you want to either use interpolated shading or have the colours change with the colour map, then you want to plot your data as a mesh and set the edgecolor property appropriately. Note that in order to plot it as a mesh, then you will need to duplicate it so that it has a size of at least 2 in each direction.
h = mesh([X(:) X(:)], [Y(:) Y(:)], [Z(:) Z(:)], [C(:) C(:)], ...
'EdgeColor', 'interp', 'FaceColor', 'none');
You may also want to look at the MeshStyle property, if you want to plot multiple lines simultaneously.
This solution is also much nicer than the one used in cline because it only creates one graphics object, rather than n.
Have a look into the cline.m function from file exchange, I think it is exactly what you need.
I can recommend the Colored line entry from the file exchange. It has good feedback and uses the color map to define the displayed colours, I've use it sucessfully on a number of projects.