# Bruno Luong

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**Content Feed**

Preallocate variables with unkown size

You can compute exactly the size needed for your vectors A = G_orig.adjacency; A(inActive,:) = 0; m = nnz(A(:,inActive)); ph...

3 days ago | 0

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Reshape Nx1 struct with field of Mx1 elements to N*Mx1 vector

Something like B = cat(1,A.bar)

4 days ago | 0

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cumulative sum table over group

tableA = {"A" 1 0 3 ; "A" 1 2 3 ; "A" 1 3 3 ; "A" 2 0 2; "A" 2 2 ...

6 days ago | 1

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Question

What means "MATLAB connector is not running"?

I have a GUI app that runs fine under MATLAB, however when compiled as standalone with MCC, I get a strange warning message "w...

6 days ago | 1 answer | 0

### 1

answermulti array vectorization problem (reformulated)

A = [ -0.8013 -0.4981; -0.2278 -0.9009]; t = 0:3; % eigen space [V,D]=eig(A,'vector'); D = reshape(D,1,[]); % compu...

7 days ago | 2

Find differences in a set of points without a for loop

x = randi(10,3,1) d = abs(x - x.')

7 days ago | 0

Rotate the coordinate system to align an existing plane with Y'Z' plane

Take a look at this thread and see if you can use it

10 days ago | 0

replace matrix A with the values of another matrix B

A= cat(3, [ 0 0 1; 0 1 0; 0 1 1], ... [1 0 0, 0 0 0; 0 0 0], ... [0 1 ...

11 days ago | 1

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Can anyone please vectorize the code I have?

There is nothing in your data to guess that Jout must have 14 elements, the last index > 0 is 13. J_org = [ 0 2 0 ...

12 days ago | 0

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Variable f coeffficient depends on x for linprog

Solve 2 problems f= [0 f2]; x = linprog(f,A,b,Aeq,beq,lb1,up1); with lb1 = -inf(size(x)), up1 = zeros(size(x)); g= [50 f2]; ...

22 days ago | 0

Computing Euclidean distance between 2 points

For a row vector d % sum(d.^2) is equal to % d*d' Example d=randi(10,1,3) sum(d.^2) d*d'

23 days ago | 1

Standalone compiled with Matlab compiler doesn't work

Have you include PSD_FSE3D.xml in the packaging? Do you take into account the path of the file is different when you run in sta...

26 days ago | 0

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Surface plot of function over triangular domain

P1 = [1,1]; P2 = [2,0.5]; P3 = [4,4]; zfun = @(x,y) x.^2+y.^2; % Create triangular mesh of triangla P1,P2,P3 n=20; [I,J]...

27 days ago | 1

swaping 2 random numbers from array

ij = randperm(length(x)-1,2)+1; x(ij) = x(flip(ij));

27 days ago | 0

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Warning: Matrix is close to singular or badly scaled. Results may be inaccurate.

It's a warning (not really error) It means your matrix is numerically not invertible (or almost not invertible)

28 days ago | 0

when edit figure error "undefined function mtimes for input arguments of type string"

can you type dbstop if error on MATLAB command window, then try to trigger the error?

28 days ago | 1

Matrix from measured data is singular, what could be the reason?

Could you try the normalization similar to my answer here?

28 days ago | 0

I want to find out points whose coordinates are within the volume formed by a cone shape.

Assuming the cone center is C: (3 x 1) coneangle is the cone angle (0 to pi, pi corresponds to the extreme case where the con...

28 days ago | 0

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Plot differential equations with respect to two variables in a 3d plane

Try this (adapt to your code): %editparams; %file that contains parameters Tend = 10; Nt = 100; % Define RHS functions RHS ...

29 days ago | 0

Generating a Dictionary Function

You can use container.Map. I give here example of numbers, but it can handle char array or strings as well. The time access, u...

29 days ago | 0

For consistency with "nan", wouldn't it be nice to be able to issue "missing(3)"?

Why not define your own function mymissing mymissing(3) mymissing(2,3) mymissing(2,'string') mymissing(2,3,'double') fun...

29 days ago | 0

Execution of script nchoosek as a function is not supported

Please do that which nchoosek you must find somewhere similar to the above or this C:\Program Files\MATLAB\R2022a\toolbox\ma...

29 days ago | 0

time date to datenum and datenum to datetime

I make a round conversion so you can convert any format to any other by using the appropriate substeps dt=datetime(2022,04,28,1...

30 days ago | 1

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Hello everyone.I'm new to the community, please help me to use matlab to calculate the volume of this 3D Shape

u=linspace(0,1,31); v=linspace(0,2*pi,37); [u,v]=meshgrid(u,v); x=(1-u).*(3+cos(v)).*cos(4.*pi.*u); y=(1-u).*(3+cos(v)).*sin...

1 month ago | 2

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VertCat unique rows of multiple tables.

% dummy test data Filename1=["a"; "b"; "c"]; Data1=["a1"; "b1"; "c1"]; T1=table(Filename1,Data1,'VariableNames',{'Filename','...

1 month ago | 0

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how to multiply a curve (in a plot) by -1, if you do not have the original data? (I only have the plotted data.)

Plot your figure, you can then retrieve the data with x = get(findobj(gcf,'Type','line'), 'xdata') y = get(findobj(gcf,'Type',...

1 month ago | 0

I am looking for a way to include duplicates into ismember function

Why use ismember at all (at least in that way)? O = Osw( interp1(a,1:length(a),y, 'nearest'))

1 month ago | 1

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How to calculate the width that contains 60% of the total area of peaks?

load Intensity.mat load position.mat ifun=@(x) interp1(x2,Int,x,'linear','extrap'); I0=integral(ifun,x2(1),x2(end)) x = fz...

1 month ago | 0

Rotate an Ellipsoid towards a point

axlgt = [5,1,1]; P = [5;6;7]; [~,i] = max(abs(axlgt)); ei = accumarray(i,1,[3,1]); a=cross(P,ei); T=makehgtform('axisrota...

1 month ago | 0

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How to find a permutation matrix to turn a general hermitian matrix into a block diagonal one?

A = [1, 0, 1; 0, 1, 0; 1, 0, 1], p=symrcm(A) A(p,p)

1 month ago | 0