If I set a time interval, [0 10], and I plot something according to that time interval, plot(t, y()), then the graph will have its x-axis going all the way to 11.
It used to not do this. It used to produced a better fitting graph, but now it produces a graph with white space attached to the end of the graph between points 10 and 11.
I must have accidentally changed a setting. How do I get the plot function to best fit the graph?
If you want to make a polished plot, you almost always have to adjust the plot axis limits yourself. Some useful commands:
axis tight; %Squeeze the data as closely as possible
xlim([xMin xMax]); %Adjust the x axis limits, do not touch the y limits
ylim([yMin yMax]);
axis([xMin xMax yMin yMax]); %Adjust all axis limits
You your case you would probably add a line like this to your code:
xlim([min(t) max(t)]);
Or, if you know that t is sorted (very common)
xlim(t([1 end]));
Related
I'd much rather be asking you about Bayesian analysis over this, but unfortunately, I am terrible with MATLAB plots (not due to a lack of effort though).
I have a plot attached. It contains 1739 days of data. I need to do the following three things:
Focus in on the plot so that the y axis limits are -1 and 1 (right now they are -4 and 14). I'm uninterested in any values beyond these limits.
Re-label the y axis from -1 to 1 in .10 increments.
Re-label the x axis so that it starts with 1, ends with 1739, and has enough points in between that it is still readable.
I've studied gca, datetick, ax=gca, etc. but I cannot accomplish any of these tasks without messing up the plot.
I am gracious for any assistance provided.
Changing the axis limits is very simple,
axis([1 1739 -1 1]) %// [xMin xMax yMin yMax]
And for the tick marks, do
set(gca,'XTick',-1:.1:1,'YTick',1:79:1739) %// 2*79 might be better than 79
after you create the plot. You can (should?) replace gca with the handle to the plot (do h=plot(... when you make the plot, then set(h,'XTick',...).
You should also go through Matlab Plotting Basics which goes through all this kind of stuff in good detail.
I am working on matlab programming, my problem is that in the same graph on y axis i need to have variable scaling, for example from 0.1 to 1 i need to have a gap between scales 0.1, but after 1 I need to have scale gap of 2, is there some command available for the same?
There is an example by The Mathworks on Matlab answers which does pretty much what you want to achieve. The idea is to create 2 axes on the same figure and use one axes to plot some data (eg. for the 0.1:0.1:1 tick marks) and the rest on the other axes. Then you overlay both axes with a transparent background:
%Create two overlapping axes
axes_handle_1 = axes;
axes_position = get(axes_handle_1, 'Position');
axes_handle_2 = axes('Position', axes_position);
%Create some data with a large gap in the x domain
my_x_data = [1:10 25:35];
my_y_data = rand(1, length(my_x_data));
%Plot the two sections of data on different axes objects
plot(axes_handle_1, my_x_data(1:10), my_y_data(1:10))
plot(axes_handle_2, my_x_data(11:end), my_y_data(11:end))
%Link the y axis limits and fontsize property of the axes objects
linkaxes([axes_handle_1 axes_handle_2], 'y');
linkprop([axes_handle_1 axes_handle_2], 'FontSize');
%Set the x range limits and tick mark positions of the first axes object
set(axes_handle_1, 'XLim', [1 21], ...
'XTick', [1 5 10])
%Set the x range limits and tick mark positions for the second axes object.
%Also set the background color to 'none', which makes the background
%transparent.
set(axes_handle_2, 'Color', 'none', ...
'YTickLabel', [], ...
'XLim', [14 35], ...
'XTick', [25 30 35])
It's quite straightforward and to my knowledge there is no built-in way to do it otherwise, except maybe with submissions from the File Exchange. Anyhow if you have questions about the above code please ask!
Please use gca property of matlab. In gca you can set a variable as your scales. Make that variable by merging two different scales
x=[1:80];
y=[.1:.1:8];
figure
plot(x,y);
%First Scale
scale1=[.1:.1:1];
%New scale is being started from 3. If we start from 1, 1 will be repeated
scale2=[3:2:9];
%Merging two variables scale1 and scale2
set(gca,'YTick',[scale1 scale2]);
Please refer http://www.mathworks.in/help/matlab/creating_plots/change-tick-marks-and-tick-labels-of-graph.html
You can also try the idea of scaling one dataset so that it has a similar magnitude as the other data set. Here you can multiply one dataset by 100 (or any suitable scaling parameter), and then it will be similar in size to the other data set. In order to clearly mention which data has been scaled in the graph use the legend.
plot(x,data1,x,100*data2)
legend('data1','100*data2','location','southeast')
Hope this helps.
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)
I need to plot the following functions in matlab
y1=sign(x)
y2=tanh(x)
y3=(x)/(x+1)
The x-range is -5,5 with 0.1 spacing
The y-plot range should be between -1.5 to 1.5.
Each plot should have a labeled x and y axis and a legend in the lower right corner.
The only things I cant figure out is how to adjust the y plot range. Ive tried editing the actual figure but all that seems to do is distort the graph.
Is there a command within matlab that will let me adjust the y axis plot range?
The other thing I havent figured out yet is adding a legend, I can do it after the figure is created but I guess it needs to be done by matlab command.
Yes, use axis after the plot command:
axis([-5 5 -1.5 1.5])
If you only want to set the y-range without setting the x-range you can use
ylim([-1.5 1.5])
or alternatively axis([-inf inf -1.5 1.5]). I found this from the original MATLAB-source: https://de.mathworks.com/help/matlab/ref/ylim.html
PS: For trigonometric functions I would recommend to use axis equal to have equally spaced x and y-axis (see MATLAB)
how can i solve the problem of these two images automatically (with a code adaptable to different data) without having to fix the axes range for each plot (i have millions of these plots)?
problem: axis range should be smaller
problem: axis range should be bigger
also, i need axis to be correctly labeled from the first value to last (see example in comment please)
any help is highly appreciated. thank you so so much.
To set axis limit and visualize chart better you can use axis command like axis([xmin xmax ymin ymax]) where parameters set chart borders. It should help you. More information is here:
http://www.mathworks.se/help/matlab/ref/axis.html
In order to have a complete bounding box use box on.
In order to avoid large empty space around a plot (or no space at all) use xlim and ylim. Try the following:
figure
plot(x,y)
box on
x1 = min(x);
x2 = max(x);
dx = x2-x1;
y1 = min(y);
y2 = max(y);
dy = y2-y1;
fc = 10/100 % this is a factor of 10% of empty space around plot
xlim([x1-dx*fc x2+dx*fc])
ylim([y1-dy*fc y2+dy*fc])
If you want to have a tick value appear at the start and the end of the axis, you could either force it by set(gca,'Xtick',[values]), where values are those ticks you want to show; or by floor and ceil of the xlim and ylim min and max limits above.
Hope this is what you need