I would like to only show these x-values on the x-axes
xx=[0.0005 0.005 0.05 0.1 0.25 0.5 0.75 1 1.25 1.5];
Is it possible?
You can modify axis labels using XtTickLabel property. For example:
set(gca,'XTickLabel',[0.0005 0.005 0.05 0.1 0.25 0.5 0.75 1 1.25 1.5])
This will change only labels, not actual values on the plot. To check values as well you can use:
set(gca,'XTick',[0.0005 0.005 0.05 0.1 0.25 0.5 0.75 1 1.25 1.5]);
set(gca,'XScale','log'); % Your xx values seem to be logarithmic, so this can help.
Related
Based on the following code:
clear vars;
close all;
x1 = [0 0 0.01 0.09 0.1 0.11 0.2 0.3 0.35 0.50 0.64 0.8 1]
y1 = [0.05 0.10 0.15 0.20 0.25 0.30 0.38 0.42 0.45 0.48 0.52 0.86 1]
x2 = [0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.9 0.9 1]
y2 = [0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.9 0.9 1]
plot(x1, y1); hold on;
plot(x2, y2);
I need to calculate the area (green area) between the two curves, for example:
How can I calculate it?
This area is the difference of the two curves integral in the specified domain between each intersection (as mentioned by MBo). Hence, you can find the intersections using InterX and then use trapz to do this:
P = InterX([x1;y1],[x2;y2]);
area = 0;
% for each segment
% each segment is between P(1,i) and P(1, i+1)
% So we can find xsegments with idx = find(x < P(1,i+1) && x > P(1,i)) and [P(1,i) x(idx) P(1,i+1)]
% ...
area = area + abs(trapz(xsegment1i,ysegment1i) - trapz(xsegment2i,ysegment2i));
Since one of the curves is a straight line you can rotate then add up the areas from the new x axis.
The line is at 45 degrees. So the rotation matrix is
cos 45 sin 45
-sin 45 cos 45
Multiply each point in the second curve by that matrix. That gives points with the line as the new x axis. Now use area of the triangle (0.5 * width * height) to add up the areas of the fragments.
I am new to MATLAB and I need help. I have 3 matrices (A, B, and C) and I want to create a new matrix average_ABC that contains average values.
A = [ 0.3 0.5 0.9
0.14 0.36 0.1
0.9 0.5 0.14]
B = [ 0.8 0.9 0.14
0.1 0.25 0.4
0.8 0.14 0.25]
C = [0.25 0.3 0.47
0.12 0.3 0.2
0.14 0.56 0.9]
The resulting matrix will be
average_matrix = [ 0.3 0.5 0.47
0.12 0.25 0.2
0.8 0.5 0.25]
Please, any suggestion, how can I do it?
You can first concatenate your matrices along the third dimension (using cat) and then compute whatever you want using the dim parameter that is available for most functions to specify that you want to perform that operation along the third dimension.
Also you've stated that you want the average (mean), but based on your example you actually want the median. Either way, we can compute them using this method.
data = cat(3, A, B, C);
% Compute the mean
mean(data, 3)
% 0.45 0.56667 0.50333
% 0.12 0.30333 0.23333
% 0.61333 0.4 0.43
% Compute the median (which seems to be what you actually want)
median(data, 3)
% 0.3 0.5 0.47
% 0.12 0.3 0.2
% 0.8 0.5 0.25
I hope this will work
average_matrix=(A+B+C)/3.;
I want to describe surface flatness of a plane with interp2 function.
Spatial sampling points are as below.
width=[0 500];
length=[0 100 200 300 400 500 600 700 800 900 1000];
and flatness are as below, at width 0 and 500, respectively.
a = [1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1]; % flatness at width 0
b = [-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1]; % flatness at width 500
With these values, the surface shape will be like following figure.
I wanted to change this figure into following figure with interp2 function.
Below is my code.
widthq=[0 100 200 300 400 500];
flatness=[a' b'];
flatnessq=interp2(width,length,flatness,widthq,length);
But, not working with one error, 'The input data has inconsistent size.'
Can anyone explain this error and give a way how to interpolate my data with interp2 function?
The first three inputs need all to be of the same size
[W, L] = meshgrid(width, length);
The last two arguments need also to be of same size
[Wq, Lq] = meshgrid(widthq, length);
Then it should work
flatnessq=interp2(W,L,flatness,Wq,Lq);
I have two vectors
A=[0.1 0.1 0.2 0.2 0.3 0.3 0.3 0.3 0.4 0.5 0.5]
B=[0.7 0.7 0.8 0.8 0.9 0.9 0.9 0.9 1 1 1]
How to plot their stem plots and box plots at the same time?
The y-axis should be the probability of the stem plots.
What I am looking for is something like this.
Drawing the box-plots can be accomplished with
boxplot([A B], [ones(size(A)) 2*ones(size(B))], ...
'orientation', 'horizontal', 'positions', [1 1]);
After which you can add the stem plots with
hold on
stem(xa, ya);
stem(xb, yb);
where I'm not sure exactly what you are asking for for x and y.
I want to plot a bar chart in Matlab with (1) log-scale for x-axis and (2)bars in same width. But with the code below, the width of the bars are different. Can any one help? Many thanks！
xdata = [0.01 0.018 0.032 0.056 0.1 0.18 0.32 0.56 1 1.8 3.2 5.6 10];
ydata = [1.3 1.6 1.5 1.2 1.0 3.5 0.6 3.1 1.6 1.9 1.7 0.3 0.4];
bar(xdata,ydata);
set(gca,'XScale','log');
Instead of plotting xdata on a log scale, plot the log of xdata on a linear scale. Then modify labels to reflect the linear value (not the used log value).
xdata = [0.01 0.018 0.032 0.056 0.1 0.18 0.32 0.56 1 1.8 3.2 5.6 10];
ydata = [1.3 1.6 1.5 1.2 1.0 3.5 0.6 3.1 1.6 1.9 1.7 0.3 0.4];
bar(log10(xdata),ydata);
set(gca,'Xtick',-3:1); %// adjust manually; values in log scale
set(gca,'Xticklabel',10.^get(gca,'Xtick')); %// use labels with linear values