I'm currently trying to create a frequency histogram, and to do this, I had to create a bar graph that has no whitespace between the bars. However, this centers the XTickLabels in the middle of the bars. Since it's a histogram, I would like the numerical values to be at the line between each bars so that it can visually indicate intervals. Essentially, I need to shift all the tick labels to the left.
I'm using R2016a.
Looking through Mathworks only turned up answers for how to do this using line graphs, scatter plots, etc.
Use the Style argument of bar to set it to histc.
v = [6 12 17 21 28 25 19 15];
bar(v,'histc');
which gives:
Furthermore, if you're interested you can change the direction of tick marks to outwards with:
set(gca,'TickDir', 'out')
Have you tried to use the set command. For example:
%create some data
x=1:10;
y=rand(1,10);
%bar plot
bar(x,y)
%shift the x to the left 0.4
set(gca, 'XTick', x +.4)
I tried to google your problem and found this answer directly here:
XTick labels and Stacking in bar plot
Is there a reason why you aren't just using hist or the newer histogram? Investigating the source code for hist using edit hist I find that they are simply using bar with the 'hist' option. Something like this:
edges = 1:10
binwidth = 1
x = edges + binwidth/2
nn = 21:30
bar(x, nn, [min(edges), max(edges)], 'hist')
Gives
You can check the code for histogram as well to see how they are doing it there, but it's a little move involved.
Related
I'm trying to plot contour using my computed data with limited contour labels and and colors as given in the top panel of this image:
But I ended up with a slightly different plot (see the plot in the bottom of the above image).
I want to modify my plot with the following three specifications
Restrict contour labels in 2 or 3 decimal places
Remove plot labels in the area where the contours are too close to each other.
Plot with two colors as in the first image
Here is my code:
f=load('fort.15');
ngridx=180;
ngridy=180;
x=f(:,3);
y=f(:,4);
z=f(:,5);
xlin=linspace(min(x),max(x),ngridx);
ylin=linspace(min(y),max(y),ngridy);
[X,Y]=meshgrid(xlin,ylin);
Z=griddata(x,y,z,X,Y,'linear');
[c,h] = contour(X,Y,Z,20);
set(h,'LineWidth',2,'LineColor',rgb('SteelBlue'),'ShowText','on',...
'LabelSpacing',800 )
axis([0 6 -5 7])
I'm not an expert in Matlab. Please help me get the right plot.
I'm attaching my data file here.
Well, I got only 2 of 3. Deine the level in which the color has to change (here scl) and you good to go:
scl = 6.5; % switch color level;
[c1,h1] = contour(X,Y,Z,scl:max(Z(:)),'Color','r');
hold on
[c2,h2] = contour(X,Y,Z,min(Z(:)):scl,'Color','b');
clabel(c2,h2);
axis([0 6 -5 7])
The idea here is to builed your plot from two contour objects, using hold on command. the vector scl:max(Z(:)) define the levvels to show in the first contour, and the get the red color and no lables. And a similar logic works for the secound contour.
If you want to lable some red contours, or remove lables from the blue ones, you need to replace h2 in the clabel function with a vector of the levels you want to lable. If you will be mo specific in the comments I'll update my answer.
Changing the formatting of the lables, is probably possible somehow, but it's really not trivial, so I left it by now.
I have been trying to get semi-transparent circle-shape markers on a log-log scatter plot. MATLAB's own scatter plot function doesn't produce semi-transparent markers (see comments below), so I am using this wonderful tool scatter_patches from Central File Exchange and it works very well:
However, I am having issues adapting this code for a log-log scatter plot. In order to obtain a log-log scatter plot with this program, I need to fix two things:
1 . Change the axes to log scale. This can be achieved by adding following after line 61:
set(cax, 'XScale', 'log');
set(cax, 'YScale', 'log');
This produces correct log scale and grid points.
2 . However, after I fixed 1., the size of the markers was not uniform in my plot. On a log plot, the lower-value regions of the axes are zoomed-in. In the scatter_patches plot, the markers at the lower side of axes are bigger while they are smaller towards the higher-value side of axes. So, the marker size is not the same on the entire plot. I tried using log10(cSize) instead of cSize on lines 221-222, but this only slimmed the difference between the largest and smallest marker sizes. It didn't yield the same size markers on the plot.
If anyone has an idea of what I might be missing here, please share.
Any help would be greatly appreciated.
Since Matlab R2014b things got really easy. No additional functions from file exchange are required, just some undocumented features. The basic idea is to get the hidden handle of the markers and apply a value < 1 for the last value in the EdgeColorData to achieve the desired transparency.
Here we go:
%// example data
x = linspace(0,3*pi,200);
y = cos(x) + rand(1,200);
%// plot scatter, get handle
h = scatter(x,y);
drawnow; %// important
%// get marker handle
hMarkers = h.MarkerHandle;
%// get current edge and face color
edgeColor = hMarkers.EdgeColorData
faceColor = hMarkers.FaceColorData
%// set face color to the same as edge color
faceColor = edgeColor;
%// opacity
opa = 0.3;
%// set marker edge and face color
hMarkers.EdgeColorData = uint8( [edgeColor(1:3); 255*opa] );
hMarkers.FaceColorData = uint8( [faceColor(1:3); 255*opa] );
In the event it helps, I have written a collection of Matlab functions for creating semi-transparent markers in plots and legends. The files are available from MATLAB Central as the MarkerTransparency package. A few examples of how to use these functions are included in the download and there is also a Wiki on GitHub. A major benefit of this package is it enables the user to have the semi-transparent markers also appear in the legend. These functions have not been tested for scatter plots but might be easily adapted to meet your needs.
On line 192 change the line with this one:
hh(end+1) = patch( exp(cSize * sin(patchSpec) / ptsPerXUnit + xs(i)), exp(cSize * cos(patchSpec) / ptsPerYUnit + ys(i)), cColor, cPatchArgs{:}); and it will work.
I just add an exp()
Do the same operation on line 222 and 223 to be sure !
Work like a charm Anindya ;).
I've never seen a plot like the following (the plot in (a) ). Is it even possible?
According to the profile page of #Ander Biguri
Matlab can even make your dinner, if you know how to use it.
Which answers the question, if this is even possible ;-)
All we need is basic knowledge of the axes command - the rest is just tweaking to make it look nice. Let's have a look at it:
We'll start off by creating some sample data:
t = 100:220;
x1 = -(10*(t-130)).^2;
x2 = -(10*(t-150)).^2;
x3 = -(10*(t-170)).^2;
Then we'll create an initial figure with a white background
fig = figure(1);
set(fig,'Color','w');
Now we can create a new axes object and plot x1 on it:
ax(1) = axes('Position',[0.1,0.1,0.6,0.6]);
plot(ax(1),t,x1+10^4*rand(size(x1)),'-k',t,x1,'-r');
We'll remove the box around the axes, so only the x- and y-axes remain. Further we resize the plot, so we'll have enough space for the other two plots. We also set the color to none, i.e. transparent.
set(ax(1),'Color','none');
set(ax(1),'Box','off');
set(ax(1),'Position',[0.1,0.1,0.6,0.6]);
Now we need to create the second graph. We'll just create another axes object at a position which we like:
ax(2) = axes('Position',[0.2,0.2,0.6,0.6]);
plot(ax(2),t,x2+10^4*rand(size(x2)),'-k',t,x2,'-r');
set(ax(2),'Color','none');
set(ax(2),'Box','off');
and so on:
ax(3) = axes('Position',[0.3,0.3,0.6,0.6]);
plot(ax(3),t,x3+10^4*rand(size(x3)),'-k',t,x3,'-r');
set(ax(3),'Color','none');
set(ax(3),'Box','off');
And simple as that, we get something that doesn't even look that bad:
Using multiple waterfall plots, as Horchler suggested:
%// create some sample data
t=10:20:110;
x=0:1:200;
Y=bsxfun(#(x,t) normpdf(x,t,20),x,t.'); %//' fix the code formatting on SO!!
%// Make a colormap to to set the colour of the lines
colormap([1 0 0;0 0 0]);caxis=[0 1];
%// Plot the first set of lines (red ones)
h1=waterfall(x,t,Y,zeros(size(Y)));
set(h1,'FaceColor','none','LineWidth',2) %// tweak the properties
hold on
%// Plot the second set of lines (black lines), just the red lines with some noise
h2=waterfall(x,t,Y+0.002*(rand(size(Y))-0.5),ones(size(Y)));
set(h2,'LineWidth',2)
hold off
view([16 28])
we can get this:
Quick version
How can I control the x- and y-values for a 3-d bar plot in Matlab?
Details
Say we have an 10 x 20 data matrix and we plot it using bar3, and we want to set the x- and y-values. For instance:
foodat = rand(10,20);
xVals = [5:14];
yVals = [-3:16];
bar3(xVals, foodat);
xlabel('x'); ylabel('y');
Is there a way to feed it the yVals as well? Otherwise the y axes always defaults to [1:N].
Note I don't just want to change the labels using XTickLabel and YTickLabel. I need to change the actual values on the axes, because I am plotting multiple things in the same figure. It isn't enough to just change how the (wrong) axis ticks are labeled. So this is different from issues like this:
How can I adjust 3-D bar grouping and y-axis labeling in MATLAB?
Other things I have tried
When I try changing the xvals with:
set(gca,'XTick', xVals)
set(gca,'YTick', yVals)
The values are taken in, but actually show up on the wrong axes, so it seems x and y axes are switched using bar3. Plus, it is too late anyway as the bar graph was already plotted with the wrong x- and y-values, so we would end up giving ticks to empty values.
Note added
Matlab tech support just emailed me to let me know about the user contributed function scatterbar3, which does what I want, in a different way than the accepted answer:
http://www.mathworks.com/matlabcentral/fileexchange/1420-scatterbar3
I found a way of doing it. Ill give you a piece of code, then you'll need to "tidy up" , mainly the axis limits and the Xticks, as bar3 does set up the Xticks inside, so if you want others you'll need to set them manually yourself.
So the trick here is to get the Xdata from the bar3 handle. The thing here is that it seems that there is a handle for each row of the data, so you need to iterate for each of them. Here is the code with the current output:
foodat = rand(20,10);
xVals = [5:14];
yVals = [-3:16];
% The values of Y are OK if called like this.
subplot(121)
bar3(yVals, foodat);
subplot(122)
h=bar3(yVals, foodat);
Xdat=get(h,'XData');
axis tight
% Widdth of barplots is 0.8
for ii=1:length(Xdat)
Xdat{ii}=Xdat{ii}+(min(xVals(:))-1)*ones(size(Xdat{ii}));
set(h(ii),'XData',Xdat{ii});
end
axis([(min(xVals(:))-0.5) (max(xVals(:))+0.5) min(yVals(:))-0.5, max(yVals(:))+0.5])
Note: Y looks different but is not.
As you can see now the X values are the ones you wanted. If you'd want other size than 1 for the intervals between them you'd need to change the code, but you can guess how probably!
I want to draw a plot that displays y tick labels are similar to the below image. How can I do that?
thanks for your attentions
The y axis is setup as logarithmic.
you can create plots similar to this using
semilogy(xData,yData)
If you wanted the plot to look the same, you would of course need to use the semilogy to plot the data and then also add x and y axis labels using something like the following
xlabel('Fitness Evaluations');
ylabel('Error');
If you truly want to only show the powers of 10 on the y axis, meaning the power number, you can do something like as follows
labels = sort(str2num(get(gca,'YTickLabel')));
set(gca,'YTickLabel',labels);
labels = [' 1 ';'10 '; '100'];
set(gca,'YTickLabel',lbls);
This will set the YtickLabels to 1, 10 and 100. If you want LaTeX to interpret your ticklabels such that you will see (10⁰,10¹,10²), you can download this file from matlab exchange.
http://www.mathworks.com/matlabcentral/fileexchange/15986