Matt J
Professional Interests: medical image processing, optimization algorithms
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Content Feed
How can I increase the number of Fourier frequencies by adding 500 zeros to the end of the 27-sample-long signal ??
L = length(t)+500; fftx1=fft(x1, L)
ungefär 2 timmar ago | 0
Matlab does not find new method in class folder without "clear classes"
I don't know if it's intended or not, but my experience is that it only happens when your class is in a @-directory. If you put ...
ungefär 3 timmar ago | 0
Finding consecutive zeros in an array. Not able to solve using diff command
Using, https://www.mathworks.com/matlabcentral/fileexchange/78008-tools-for-processing-consecutive-repetitions-in-vectors [~,~...
ungefär 3 timmar ago | 0
Solve equation with multiple values for V
Because there is no analytical solution. Try vpasolve() or fzero() instead.
ungefär 3 timmar ago | 0
Help. Plot graph calculation
You mean, how to plot the triangle? You can do, x=linspace(0,3,1000); y=(1-abs(x-1)); y=y.*(y>=0); plot(x,y)
ungefär 8 timmar ago | 0
Intensity Profile of a specific line
You could just use improfile() https://www.mathworks.com/help/images/ref/improfile.html
ungefär 8 timmar ago | 0
Multiple plots on the same graph
I think the line where you plot is supposed to look like, semilogx(tc,PDF); but the code you've posted contains no variable c...
ungefär 8 timmar ago | 0
How to get rid of this line that connects the last and first point, I have made it white so its barely visible, but is there a way to not plot it?
plot3 (WayPTS(:,1), WayPTS(:,2), WayPTS(:,3),'black');
ungefär 8 timmar ago | 0
How to create a custom Matrix following a set of parameters
n=5; A=-diff(eye(n+2),2,1); A(:,1)=[]
ungefär 9 timmar ago | 0
How to create a custom Matrix following a set of parameters
n=5; c=[2,-1,zeros(1,n-2)]; r=[c,0]; A=toeplitz(c,r)
ungefär 9 timmar ago | 0
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How to covert a 1D vector to 2D matrix with overlapping effectively?
X=randi(30, 1,14); segment_size = 4; overlap_rate = 0.5; d=segment_size*overlap_rate; idx=(1:segment_size)'+ ( 0:d:(num...
ungefär 17 timmar ago | 0
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Plot elements of specific size
You could probably use a listener to increase the MarkerSize etc as a response to zooming in or out. The code below is an imple...
ungefär 20 timmar ago | 1
Plot elements of specific size
First, I don't care about interactive zooming. I'd like to save a pdf. If the zooming is happening only after the pdf conversio...
ungefär 23 timmar ago | 0
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how to write a function which converts graphs from linear scale to logarithmic scale and plot them both?
To convert the scale of an existing graph from linear to log, you can do, set(gca,'YScale','log') set(gca,'XScale','log')
ungefär 24 timmar ago | 0
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Cropping the same roipoly for multiple images
I don't understand what you mean by "cropping" an image to a non-rectangular region. An image, cropped or otherwise, is an inher...
en dag ago | 0
Calculating value of function in point
f=@(x)2*x+2.^x; test = evaluate(f,0,6,7) function matrix = evaluate(f,x,y,n) a = linspace(x,y,n); b = f(a); matrix = [a;b...
en dag ago | 0
Failure in initial objective function evaluation. FSOLVE cannot continue.
Is there supposed to be a '+' after teta1s? fval(2,1)=beta1c+teta1s+((2.66*mumr...
en dag ago | 0
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How to write a function with logical condition which takes an array and turns back an array?
K=sinc(alpha/pi*(x-y.'));
en dag ago | 1
| accepted
2D matrix multiply with 3D array
[m,n,p]=size(B); Br=reshape(B,[],p); Br=Br(:,1:200); %might not be necessary U1=Br*u; V1=Br*v; c=reshape( sum(U1.*V...
en dag ago | 0
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using eig to find the eigenvalues and eigenvectors of a large matrix on GPU
It might be a question of your hardware. On the GTX 1050 in R2020b, I see only about a 10% speed-up in double precision and abou...
en dag ago | 0
| accepted
A function does not work with an array as an input argument
args={'ArrayValued',1}; MyFun = @(a, x) ( integral(@(k) k .* (1 ./ ( 1 + (a*k - x).^2 )), -1, 1,args{:}) ./ ... integral(@(k...
2 dagar ago | 1
| accepted
Rounding errors when using quadprog
There's nothing wrong with post-rounding, however setting lb(i)=ub(i)=0 for the appropriate variables should force them to an ex...
2 dagar ago | 0
Connect the optimizer function to data extracted from another software
You've written a fitness function f=@(~) e_and_r_vals(md_e,E_best_vals_from_md_r) which takes no input arguments. The fitness ...
2 dagar ago | 0
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Is there an alternative to eval in a struct?
Your data organization seems like it should be reconsidered. In a struct, it doesn't make sense if different fields have essenti...
3 dagar ago | 0
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Expressing polynomial including a indefinite parameter
Possibly you mean that you want a coefficient vector as the output, rather than a polynomial in functional form. syms a x P ...
3 dagar ago | 0
Expressing polynomial including a indefinite parameter
One way. p = @(x,a) polyval([a,-4,2-a],x); Usage: x=1; a=2; p(x,a)
3 dagar ago | 1
| accepted
Combining 3 2D graphs into a 3D figure
Something like the following, perhaps? x=linspace(0,5); z1=x.*exp(-x); z2=3*x.*exp(-4*x); Hax=axes; area(x,z1,'Parent',up...
3 dagar ago | 0
| accepted
How can I minimize absolue value in a power optimprob?
The objective is to minimize the integral of Pgrid abs value... while the control variables are Pbatt and Pev; Ppv and Pload If...
3 dagar ago | 0
| accepted
Finding out what initial guesses the curve fitting toolbox made for curve fit
I don't think there's anyway to dig out the initial guess generated inside fit(), but why not just specify your own random start...
4 dagar ago | 0
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