Matt J

Last seen: Today|Active since 2009

Professional Interests: medical image processing, optimization algorithms

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Answered
How to measure and show the center to center distance between lines at intersecting points
VDists=hypot( diff(XCrossings,1,1), diff(YCrossings,1,1)); HDists=hypot( diff(XCrossings,1,2), diff(YCrossings,1,2)); xlocs=...

21小时前| 1

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Answered
How to formulate 2D frames if I have the origin of the frames (x, y) and the inclination angle of the frame with respect to the x-axis?
T=makehgtform('translate',[x,y,0],... 'zrotate',angleDegrees*pi/180, ... 'translate',[-x0,-y0,0]);...

1 day ago | 0

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Basic Elements in MATLAB Solutions : Geometric Modelling and CAD Solutions Part 2
function Xnew=rotation(X,x0,theta) R=makehgtform('zrotate',theta); Xnew=R(1:2,1:2)*(X-x0)+x0; end function ...

2 days ago | 0

Answered
How to get the value from Structure array ?
I want to use the centroid location in this image to crop another image then save the cropped area to separate file. I=imread(...

2 days ago | 0

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arg max data type
没有,但是你就不能丢给一个整数类型post-facto? E.g., ix=cast(ix,'uint32');

2 days ago | 0

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how can i obtain the paraconjugate of a polynomial of any degree ?
poly( conj( roots(p) ) )

2 days ago | 0

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Create new matrices based on the number of unique values
M = [4 7 2; 2 4 7; 2 2 4]; x=reshape(unique(M),1,1,[]); output=(M==x)

2 days ago | 1

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How can I combine two images to form an image like this?
Perhaps with this? //www.tianjin-qmedu.com/matlabcentral/fileexchange/105850-automatic-panoramic-image-stitcher-autopanostitc...

2 days ago | 1

Answered
How to get the value from Structure array ?
I=imread("//www.tianjin-qmedu.com/matlabcentral/answers/uploaded_files/996660/2_mask.png"); Ibw = im2bw(I); stat = reg...

2 days ago | 0

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Answered
I am writing a code for using "fmincon" but it is having some error, Why?
Your objective function is not returning numbers. It is returning sym variables, e.g., >> fun([0,0]) ans = (6.7465e+03*...

2 days ago | 1

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Answered
for loop to subtract row from columns
Punkte_Gesamt_D_Wasserhoehe([4:371],:)=... Punkte_Gesamt_D_Wasserhoehe([4:371],:)-Punkte_Gesamt_D_Wasserhoehe(3,:);

2 days ago | 0

Answered
How to find the maximum y-value from a window I select on a graph
Perhaps you meant, ymax = max(y1,y2) xmax = max(x1,x2)

2 days ago | 0

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Filter function returns different results on different GPUs
Use double floating point, instead of single floating point. load('kilo_vars.mat') res1=filter(b1, a1, dataraw); res2...

3 days ago | 0

Answered
Add cell to table
As a simplified example, T=array2table(rand(4,5)); %A randomly generated table Headings={'dog','cat','fish','fox','hamster'}...

3 days ago | 0

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Answered
Convert Character to Integer tnat can be used for Sum-function
There is no problem. Both X = 7.952110000000000e+03 and X = 7952.11 are the same number. However if you prefer the latter displ...

3 days ago | 0

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Indicate a new quiver for each lopp
.... quiver(-dpx,dpy); hold on end end hold off

3 days ago | 0

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Answered
Curve Fitting for multiple plots in single graphs
Just concatenate the x,y, data. x=[XCS1(:);XSC2(:)]; y=[VYS1(:);VYS2(:)]; cfit = fit(x,y,fitType)

3 days ago | 0

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Answered
How to calculate the inclination angle of whole box which their 4 vertices are stored in cell array with respect to the horizontal x-axis?
boxes = cellfun(@(z) cell2mat(z(:)) ,c ,'UniformOutput' ,false) boxes=cat(3,boxes{:}); rays=normalize( boxes(4,:,:)-boxe...

3 days ago | 1

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Answered
How to calculate the centroid of these bounding boxes which their 4 vertices are stored in cell array?
centroids = cellfun(@(z) mean(cell2mat(z(:))) ,c ,'UniformOutput' ,false)

3 days ago | 1

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Answered
Counting outcomes of names
Something like this, perhaps? investors=["Sam";"Joe";"Sam and Joe"] contains(investors,"Sam")

3 days ago | 0

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Answered
How to count the number of pixels in each section of an image set?
A = imread('toyobjects.png'); A = A<100 | A>150; % some binary image % get total number of pixels across all objects pixt...

3 days ago | 2

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Answered
Merge the output from regionprops 'BoundingBox' into the format required for groundTruth.
Let's say you have bounding box data from calling regionprops on some number of image frames. Then, your loop to organize the bo...

3 days ago | 0

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Answered
permutations of 4 numbers in 7 positions IF the sum of the numbers is 600
See the attached file. combos = diophantine(ones(1,7),600,[0,100,125,75,50]) all(sum(combos,2)==600)

3 days ago | 0

Answered
while loop not performing
A=[-0.2 0.1; 0.1 -2]; vm=[1; 1]; vm=vm/norm(vm); while (1) term=A*vm; nterm=norm(term); ea= nterm-ab...

3 days ago | 0

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Answered
Revolving a curve about the y-axis to generate a 3D surface
Why not just revole around whatever axis cylinder() acommodates and then use rotate? Or, interchange the data when you plot, e....

4 days ago | 0

Answered
Can I pass a variable to the outside of a for loop after each iteration?
Is there any way this is possible? Sure. For example, n=3; i=1; while i<200 disp("i="+i+" n="+n) ...

4 days ago | 0

Answered
I would like to pick the consecutive cells those satistfies my given condition
You might benefit from downloading, //www.tianjin-qmedu.com/matlabcentral/fileexchange/78008-tools-for-processing-consecutive...

4 days ago | 0

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Answered
How can i write three different condition in a single loop
for i=1:N if i==1 elseif i

4 days ago | 0

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Answered
I want to use GA algorithm, but it gives me this error "Not enough input arguments. "
x = ga(@flc_cost_fcn,17,[],[],[],[],LB,UB,[],options);

4 days ago | 0

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Answered
3D mesh - Limit Z axis height, but just for the function, not the entire 3D domain
One possibility. X=linspace(0,2,20); Y=linspace(-5,1,20); [X,Y]=meshgrid(X,Y); Z=((Y.^2)); Z(Z>=4)=nan; surf(X,Y,Z); ...

4 days ago | 1

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