How could one break the x axis in the same figure (not the subplot function)?
You can see an example in line graph in panel b in the following picture, one single row data have been split into three parts as well as the x axis.
the question is how this plot can be achieved in matlab.
(like the panel b in this figure)
Ill leave you an exmaple here using surf.
The trick is inserting nans wherever you want the lines to appear "empty"
z=peaks(100);
% If you want to delete a certain amount of rows/cols
z2=z;
z2(:,10:15)=NaN;
z2(:,50:55)=NaN;
z2(:,75:80)=NaN;
% If you want to separate you data without deleting anything
z3=z;
z3=[z3(:,1:15) nan(size(z3,1),5) z3(:,16:75) nan(size(z3,1),5) z3(:,75:100) ];
% This last bit is only for plotting, so you can try it in your computer
subplot(131)
title('Original')
surf(z,'edgecolor','interp')
axis off
view(2)
axis equal
subplot(132)
title('Deleted columns')
surf(z2,'edgecolor','interp')
axis off
view(2)
axis equal
subplot(133)
title('Separatedd data')
surf(z3,'edgecolor','interp')
axis off
view(2)
axis equal
There are a couple of utilities on the File Exchange that allow you to do that:
Break X Axis
BreakXAxis
Related
Is it possible to make multiple vertical histograms plot in Matlab into one? Much like the excel sheet enclosed ( https://drive.google.com/file/d/1H_mbyrIoln3XrnK1hLajnVNBKn13y_np/view?usp=sharing )
I want to make a plot of many vertical histogram plots into one figure, by importing excel-files, where on the y axis it has the elevation, the x axis the distance between the histogram vertical lines and the length of the histogram bars is the values in the excel sheet. The vertical height of each bar is 5.
Is this even possible? I have to put in a number of conditions for Matlab to know where to plot, but could some one show me the basic methodology?
Help would be very much appreciated!
The problem is that the parent of a Baseline object is the Axis, which prevents us from doing something like
barh(bins1,counts1,'Basevalue',baseline1); hold on;
barh(bins2,counts2,'Basevalue',baseline2); hold off;
because the plots will automatically share the second baseline value set. There might be a workaround for this that I do not know of, so I invite anybody who knows it to show me how its done.
For now, I was able to sort-of replicate the plot you posted a picture of in a much less elegant way. I will post code below, but before I do, I would like to argue against the use of a plot like this. Why? Because I think it is confusing, as the x-axis both relates to the plot number as well as the bin count numbers. You are in fact trying to display a 3-D data set, the three dimensions being bins, bin counts, and 'histogram number'. A plethora of methods exist for displaying 3-D data, and a series of 2-D histograms may not be the best way to go.
That being said, here is a code that more-or-less creates the picture above, as promised. Any changes you may want to make will be more cumbersome than usual :-)
testData = randn(10000,1); % Generate some data
[counts,bins] = hist(testData); % Bin the data
% First histogram
baseline1 = 0;
p1=subplot(1,3,1); barh(bins,counts,'BaseValue',baseline1);
xticks(baseline1); xticklabels({0}); % Graph number on x axis at baseline (0)
box off; % Remove box on right side of plot
ylabel('Property');
% Second histogram
baseline2 = max(counts)*1.2;
sepdist = baseline2-baseline1; % Distance that separates two baselines
counts2 = baseline2 + counts;
p2=subplot(1,3,2); barh(bins,counts2,'BaseValue',baseline2)
xticks(baseline2); xticklabels({1}); % Graph number on x axis at baseline
box off;
Y=gca; Y.YAxis.Visible='off';
p1p=p1.Position; p2p=p2.Position;
p2p(1)=p1p(1)+p1p(3); p2.Position=p2p; % Move subplot so they touch
% Third histogram
baseline3 = baseline2 + sepdist;
counts3 = baseline3+counts;
p3=subplot(1,3,3); barh(bins,counts3,'BaseValue',baseline3)
xticks(baseline3); xticklabels({2});
Y=gca; Y.YAxis.Visible='off';
box off
p3p=p3.Position;
p3p(1)=p2p(1)+p2p(3); p3.Position=p3p;
% Add x-label when you are done:
xl=xlabel('Test xlabel'); xl.Units='normalized';
% Fiddle around with xl.Position(1) until you find a good centering:
xl.Position(1) = -0.49;
Result:
I have graphed a Bode plot for my transfer function, and I was wondering if there is some way to insert either horizontal or vertical lines to show a specific value for the gain/phase angle or frequency?
I have found with the following code I can draw a horizontal line on the phase angle graph:
x = linspace(10^-1,10^2,100);
for bleh = 1:length(x)
y(bleh) = -30.9638;
end
bode(num, den)
hold on
plot(x,y)
But this does not seem to apply in the gain graph, nor does my limited knowledge (and only way that makes sense to me) of vertical lines. I tried:
y1 = get(gca,'ylim');
w1 = 1.2;
bode(num, den)
hold on
plot(x,y,[w1 w1],y1)
But I only get the one horizontal line as was done from the above code.
Is this a possibility?
(Using R2017a, if that matters.)
I'm not sure I've understood you question, nevertheless, I propose the following.
When there are more one axes in a figure, as it is the case of the bode diagram, if you want to add something in a specific axes (or in all) you have to specify, in the call to plot the handle of the axes.
So, to add lines in the bode diagram, you have first to identify the handles of the two axes: you can do it in, at least two way:
using the findobj function: ax=findobj(gcf,'type','axes')
extract them as the Children of the figure: ax=get(gcf,'children')
Once you have the handles of the axes, you can get their XLim and YLim that you can use to limit the extent of the line you want to add.
In the following example, I've used the above proposed approach to add two lines in each graph.
The horizontal and vertical lines are added in the middle point of the X and Y axes (problably this point does not have a relevant meaning, but it is ... just an example).
% Define a transfer function
H = tf([1 0.1 7.5],[1 0.12 9 0 0]);
% PLot the bode diagram
bode(H)
% Get the handles of the axes
ax=findobj(gcf,'type','axes')
phase_ax=ax(1)
mag_ax=ax(2)
% Get the X axis limits (it is the same for both the plot
ax_xlim=phase_ax.XLim
% Get the Y axis limits
phase_ylim=phase_ax.YLim
mag_ylim=mag_ax.YLim
%
% Define some points to be used in the plot
% middle point of the X and Y axes of the two plots
%
mid_x=(ax_xlim(1)+ax_xlim(2))/2
mid_phase_y=(phase_ylim(1)+phase_ylim(2))/2
mid_mag_y=(mag_ylim(1)+mag_ylim(2))/2
% Set hold to on to add the line
hold(phase_ax,'on')
% Add a vertical line in the Phase plot
plot(phase_ax,[mid_x mid_x],[phase_ylim(1) phase_ylim(2)])
% Add an horizontal line in the Phase plot
plot(phase_ax,[ax_xlim(1), ax_xlim(2)],[mid_phase_y mid_phase_y])
% Set hold to on to add the line
hold(mag_ax,'on')
% Add a vertical line in the Magnitide plot
plot(mag_ax,[mid_x mid_x],[mag_ylim(1) mag_ylim(2)])
% Add an Horizontal line in the Magnitide plot
plot(mag_ax,[ax_xlim(1), ax_xlim(2)],[mid_mag_y mid_mag_y])
Hope this helps,
Qapla'
I have plotted a figure with multiple lines on it, and I have noticed that the lines for the plot overlap the x-axis when they are zero. Is there a way that I can essentially get the x-axis to plot on the top, rather than the lines?
Here is a MWE that does the same thing (I haven't put my exact code up as my dataset is quite big).
xdata=1:1:10;
ydata=[1;0.8;0.6;0.4;0.2;0;0;0;0;0];
line(xdata,ydata)
After I plot the lines (multiple per plot in my case), I do various other things with the axes so I get what I need (including adding a secondary set of axes). None of this seems to make any difference as to whether the x-axis is plotted on top of the lines or not.
I did have a search online but couldn't find anything to do with this.
The answer given by Luis is a nice workaround, but the official way to solve this problem is to use the layer property of the axis object, see the manual. To plot the axis on top of the data you do
set(gca,'Layer','top')
To automatically do this for all your plots, you can put the following line in your startup.m:
set(0,'DefaultAxesLayer','top')
This kind of answers you do not make up yourself, I only discovered this trick after asking more or less the same question on comp.soft-sys.matlab many years ago. See also this SO question.
After having plotted all your lines, plot a line on the x axis with the same color as the axis:
hold on
a = axis; %// gives xmin xmax ymin ymax
cx = get(gca,'Xcolor'); %// color of x axis
plot([a(1) a(2)], [a(3) a(3)], 'color', cx)
If the lines also overlap with the y axis and you also want that axis to appear on top, add the following:
cy = get(gca,'Ycolor'); %// color of y axis
plot([a(1) a(1)], [a(3) a(4)], 'color', cy)
All the three variables I am using to plot are matrix of size 1x1x100. I am using this code line to plot:
hold on;
for i=1:100
plot3(R_L(:,:,i),N_Pc(:,:,i),CO2_molefraction_top_of_window(:,:,i),'o');
xlabel('R_L');
ylabel('N_P_c');
zlabel('CO_2')
end
However, I am not getting the third axis, and hence the third variable CO2_molefraction_top_of_window on the plot. May I know where am I wrong?
Besides the above question, but on the same subject, I want to know if there is any option where I can plot 4 dimensional plot just like the 3 dimensional plot which can be drawn using plot3?
So I had the same problem when using plot3. For some reason, using the hold on command "flattens" the plot. I'm not sure why, but I suspect it has something to do with the operation hold on performs on the plot.
Edit: To clarify, the 3d plot is still there, but the perspective has been forced to change. If you use the "rotate 3D" tool (the one with an arrow around a cube), you can see the graph is 3d, the default perspective is just straight on so only two axes are visible and it appears flat.
Just a note --- you only need to do the xlabel ylabel zlabel commands once (outside the loop).
Also:
is there any reason your matrices are 1x1x100 instead of just 100x1 or 1x100?
Because if you reshape them to 2D you can just do the plotting in one hit.
What do you mean by "missing third axis"? When I run your code (or as close as I can get, since you didn't provide a reproducible example), I do get a 3rd axis:
.
X = rand(1,1,100); % 1x1x100 X matrix
Y = rand(1,1,100); % 1x1x100 Y matrix
Z = rand(1,1,100); % 1x1x100 Z matrix
% Now, we could do a for loop and plot X(:,:,i), Y(:,:,i), Z(:,:,i),
% OR we can just convert the matrix to a vector (since it's 1x1x100 anyway)
% and do the plotting in one go using 'squeeze' (see 'help squeeze').
% squeeze(X) converts it from 1x1x100 (3D matrix) to 100x1 (vector):
plot3(squeeze(X),squeeze(Y),squeeze(Z),'o')
xlabel('x')
ylabel('y')
zlabel('z')
This gives the following, in which you can clearly see three axes:
If it's the gridlines that you want to make the graph look "more 3D", then try grid on (which is in the examples in the Matlab help file for plot3, try help plot3 from the Matlab prompt):
grid on
You will have to clarify "missing third axis" a bit more.
I came across a similar problem and as #Drofdarb's the hold on seems to flatten out one axis. Here is a snippet of my code, hope this helps.
for iter = 1:num_iters:
% hold on;
grid on;
plot3(tita0,tita1, num_iters,'o')
title('Tita0, Tita1')
xlabel('Tita0')
ylabel('Tita1')
zlabel('Iterations')
hold on; % <---- Place here
drawnow
end
As opposed to:
for iter = 1:num_iters:
grid on;
hold on; % <---- Not here
plot3(tita0,tita1, num_iters,'o')
title('Tita0, Tita1')
xlabel('Tita0')
ylabel('Tita1')
zlabel('Iterations')
% hold on;
drawnow
end
I have multiple subplots in one figure. The X axis of each plot is the same variable (time). The Y axis on each plot is different (both in what it represents and the magnitude of the data).
I would like a way to zoom in on the time scale on all plots simultaneously. Ideally by using the rectangle zoom tool on one of the plots, and having the other plots change their X limits accordingly. The Y limits should remained unchanged for all of this. Auto fitting the data to fill the plot in the Y direction is acceptable.
(This question is almost identical to Stack Overflow question one Matplotlib/Pyplot: How to zoom subplots together? (except for MATLAB))
Use the built-in linkaxes function as follows:
linkaxes([hAxes1,hAxes2,hAxes3], 'x');
For more advanced linking (not just the x or y axes), use the built-in linkprop function
Use linkaxes as Yair and Amro already suggested. Following is a quick example for your case
ha(1) = subplot(2,1,1); % get the axes handle when you create the subplot
plot([1:10]); % Plot random stuff here as an example
ha(2) = subplot(2,1,2); % get the axes handle when you create the subplot
plot([1:10]+10); % Plot random stuff here as an example
linkaxes(ha, 'x'); % Link all axes in x
You should be able to zoom in all the subplots simultaneously
If there are many subplots, and collecting their axes handle one by one does not seem a clever way to do the job, you can find all the axes handle in the given figure handle by the following commands
figure_handle = figure;
subplot(2,1,1);
plot([1:10]);
subplot(2,1,2);
plot([1:10]+10);
% find all axes handle of type 'axes' and empty tag
all_ha = findobj( figure_handle, 'type', 'axes', 'tag', '' );
linkaxes( all_ha, 'x' );
The first line finds all the objects under figure_handle of type "axes" and empty tag (''). The condition of the empty tag is to exclude the axe handles of legends, whose tag will be legend.
There might be other axes objects in your figure if it's more than just a simple plot. In such case, you need to add more conditions to identify the axes handles of the plots you are interested in.
To link a pair of figures with linkaxes use:
figure;imagesc(data1);
f1h=findobj(gcf,,’type’,’axes’)
figure;imagesc(data2);
f2h=findobj(gcf,,’type’,’axes’)
linkaxes([f1h,f2h],’xy’)