Professional Interests: medical image processing, optimization algorithms

PLEASE NOTE: I do not read email sent through my author page. Please post questions about FEX submissions in their respective Comments section.

Answered

Relocate a value of a vector.

A=[1 2 3 4 5 6 7 8 9 0]; i=2; %position removed j=7; %target position B=A; k=i<j; B(i)=inf; C = [B(1:j+k-1),A(i),...

Relocate a value of a vector.

A=[1 2 3 4 5 6 7 8 9 0]; i=2; %position removed j=7; %target position B=A; k=i<j; B(i)=inf; C = [B(1:j+k-1),A(i),...

23 hours ago | 2

| accepted

Answered

table less than operator

Are you sure you do not instead want to compare the content of a variable in the table to something?... yes this what I'm trying...

table less than operator

Are you sure you do not instead want to compare the content of a variable in the table to something?... yes this what I'm trying...

24 hours ago | 0

Answered

Why is N not being displayed?

Because the loop condition is never satisfied and therefore nothing within it is ever executed. I think you meant to have, whil...

Why is N not being displayed?

Because the loop condition is never satisfied and therefore nothing within it is ever executed. I think you meant to have, whil...

1 day ago | 0

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Answered

Displaying information about the data set by clicking on its plot and then show a value that is associated with the (x,y) point

.... set(dcm,'UpdateFcn',@(t,e) myupdatefcn(t,e,x,y) ); function txt = myupdatefcn(~,event,xdata,ydata) pos = get(eve...

Displaying information about the data set by clicking on its plot and then show a value that is associated with the (x,y) point

.... set(dcm,'UpdateFcn',@(t,e) myupdatefcn(t,e,x,y) ); function txt = myupdatefcn(~,event,xdata,ydata) pos = get(eve...

1 day ago | 0

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Answered

Getting the linear portion of a non-linear curve

I'm not sure why a 2nd derivative test wouldn't have worked, as long as your points are noiseless: i=find( abs(diff(x,2))>somet...

Getting the linear portion of a non-linear curve

I'm not sure why a 2nd derivative test wouldn't have worked, as long as your points are noiseless: i=find( abs(diff(x,2))>somet...

1 day ago | 1

Answered

How to return the smallest vector.

If you "have them" in cell array form, then you could do something like this: >> vectors={[3 4 5],[1,2],[5 6 7 8]} vectors =...

How to return the smallest vector.

If you "have them" in cell array form, then you could do something like this: >> vectors={[3 4 5],[1,2],[5 6 7 8]} vectors =...

2 days ago | 0

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Answered

a problem with setting fmincon options?

I would guess that you entered your options object as the 9th input argument to fmincon when it really should be the 10th. If yo...

a problem with setting fmincon options?

I would guess that you entered your options object as the 9th input argument to fmincon when it really should be the 10th. If yo...

2 days ago | 0

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Answered

set Precision in lsqcurvefit

You cannot do such a thing with lsqcurvefit. What you describe would require that you rewrite your objective function and bounds...

set Precision in lsqcurvefit

You cannot do such a thing with lsqcurvefit. What you describe would require that you rewrite your objective function and bounds...

2 days ago | 2

Answered

Delete part of an image

[m,n]=size(oldImage); x=(1:n); y=(1:m).'; mask = (x-innerCenterX).^2+(y-innerCenterY).^2>=innerRadius^2 & ... (x...

Delete part of an image

[m,n]=size(oldImage); x=(1:n); y=(1:m).'; mask = (x-innerCenterX).^2+(y-innerCenterY).^2>=innerRadius^2 & ... (x...

2 days ago | 2

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Answered

Find the orientation of the skeletonized image

You can use houghlines to get the endpoints of all the line segments in the image. From that, you can easily calculate their slo...

Find the orientation of the skeletonized image

You can use houghlines to get the endpoints of all the line segments in the image. From that, you can easily calculate their slo...

2 days ago | 0

Answered

Using cell array to define Argument list in function Handle

That is not the right approach. You should be taking advantage of the fact that this is Matlab, and that your variables are allo...

Using cell array to define Argument list in function Handle

That is not the right approach. You should be taking advantage of the fact that this is Matlab, and that your variables are allo...

3 days ago | 0

Answered

Divide plane into two separate planes

Let b1 and b2 be basis vectors for the plane and let x0 be a point in the plane. Then, for example, x0(:) + b1(:)*randn(1,N) + ...

Divide plane into two separate planes

Let b1 and b2 be basis vectors for the plane and let x0 be a point in the plane. Then, for example, x0(:) + b1(:)*randn(1,N) + ...

3 days ago | 0

Answered

how to plot values that only fall within a range?

KPH_70 = mean(Y(FVY)); yyaxis left plot(X(FVY),Y(FVY)); yyaxis right plot(X(FVY),KPH_70*ones(size(FVY)));

how to plot values that only fall within a range?

KPH_70 = mean(Y(FVY)); yyaxis left plot(X(FVY),Y(FVY)); yyaxis right plot(X(FVY),KPH_70*ones(size(FVY)));

3 days ago | 0

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Answered

How to pass a vector to a function that creates matrix

>> b=[1 2 3]*10; >> T=@(i) [b(i)+9 , 8 ; 8 , 7 ]; >> T(3) ans = 39 8 8 7

How to pass a vector to a function that creates matrix

>> b=[1 2 3]*10; >> T=@(i) [b(i)+9 , 8 ; 8 , 7 ]; >> T(3) ans = 39 8 8 7

3 days ago | 0

Answered

how to calculate direction in rotated coordinate system

Using AxelRot (Download), and assuming all angles are given in radians, [x,y,z] = sph2cart(Azi_Old,Elev_Old,1); P=AxelRot( ...

how to calculate direction in rotated coordinate system

Using AxelRot (Download), and assuming all angles are given in radians, [x,y,z] = sph2cart(Azi_Old,Elev_Old,1); P=AxelRot( ...

4 days ago | 0

Answered

How to work with Nelder-Mead algorithm with 7 unknown variables?

You can use fminsearch (an implementation of Nelder-Mead) with any number of variables. However, there is no way to gaurantee th...

How to work with Nelder-Mead algorithm with 7 unknown variables?

You can use fminsearch (an implementation of Nelder-Mead) with any number of variables. However, there is no way to gaurantee th...

4 days ago | 2

Answered

f(x)=sin(x)-x^5=0 providing x is not equals 0 ,function in the interval x [0,3]

>> [x0,fval]=fzero(@(x)sin(x)-x.^5,[0.8,1]) x0 = 0.9610 fval = -1.1102e-16

f(x)=sin(x)-x^5=0 providing x is not equals 0 ,function in the interval x [0,3]

>> [x0,fval]=fzero(@(x)sin(x)-x.^5,[0.8,1]) x0 = 0.9610 fval = -1.1102e-16

4 days ago | 0

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Answered

Generating Toeplitz Matrix which Matches the Convolution Shape Same

Using interpMatrix (Download), nH=numel(vH); nX=numel(vX); ic=ceil( (nH+1)/2); mH = interpMatrix(vH,ic , nX,1);

Generating Toeplitz Matrix which Matches the Convolution Shape Same

Using interpMatrix (Download), nH=numel(vH); nX=numel(vX); ic=ceil( (nH+1)/2); mH = interpMatrix(vH,ic , nX,1);

4 days ago | 0

Answered

Generating Toeplitz Matrix which Matches the Convolution Shape Same

I am specifically asking about using the function toeplitz(). If it must be with toeplitz, then: nH=numel(vH); nX=numel(vX); ...

Generating Toeplitz Matrix which Matches the Convolution Shape Same

I am specifically asking about using the function toeplitz(). If it must be with toeplitz, then: nH=numel(vH); nX=numel(vX); ...

4 days ago | 0

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Answered

Concatenating matrices in a file into another matrix

For example, >> p1=[1,2,3]; p2=[4 5 6]; p3=[7 8 9]; save p p1 p2 p3 >> A=cell2mat(struct2cell(load('p'))) A = 1 ...

Concatenating matrices in a file into another matrix

For example, >> p1=[1,2,3]; p2=[4 5 6]; p3=[7 8 9]; save p p1 p2 p3 >> A=cell2mat(struct2cell(load('p'))) A = 1 ...

4 days ago | 0

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Answered

Warning: Matrix is close to singular or badly scaled. Results may be inaccurate. RCOND = 2.240406e-24.

Even with A\B, you cannot expect reliable behavior with RCOND as small as 2.240406e-24. For all intents and purposes, your mat...

Warning: Matrix is close to singular or badly scaled. Results may be inaccurate. RCOND = 2.240406e-24.

Even with A\B, you cannot expect reliable behavior with RCOND as small as 2.240406e-24. For all intents and purposes, your mat...

4 days ago | 0

Answered

Fit a conic section without mirror image hyperbola

This approach uses John's fminspleas FEX submission (Download). Although the fit is, technically, a hyperbola, it diverges to a ...

Fit a conic section without mirror image hyperbola

This approach uses John's fminspleas FEX submission (Download). Although the fit is, technically, a hyperbola, it diverges to a ...

4 days ago | 1

Answered

rotating and saving images to folder: error during loop

The code works fine for me. If I had to guess, I would say it is because you ran the code previously while debugging and never c...

rotating and saving images to folder: error during loop

The code works fine for me. If I had to guess, I would say it is because you ran the code previously while debugging and never c...

4 days ago | 0

Answered

Defining constraints in the Quadratic Programming

If you have a quadratic function of only 1 unknown variable, it should be possible to find the minimum analytically - no iterati...

Defining constraints in the Quadratic Programming

If you have a quadratic function of only 1 unknown variable, it should be possible to find the minimum analytically - no iterati...

4 days ago | 0

Answered

PARFOR: Broadcast variable

The code looks suspiciously like an attempt at weighted normalized cross-correlation. If so, see here for a possibly faster alte...

PARFOR: Broadcast variable

The code looks suspiciously like an attempt at weighted normalized cross-correlation. If so, see here for a possibly faster alte...

5 days ago | 1

Answered

Forming a block diagonal matrix of one certain matrix?

using interpMatrix (Download) S=1*ones(2); B=2*ones(2); C=3*ones(2); copies=4; %number of repetitions L=flip( {S,B,C, z...

Forming a block diagonal matrix of one certain matrix?

using interpMatrix (Download) S=1*ones(2); B=2*ones(2); C=3*ones(2); copies=4; %number of repetitions L=flip( {S,B,C, z...

5 days ago | 0

Answered

Generating Toeplitz Matrix which Matches the Convolution Shape Same

Using func2mat (Download), mH=func2mat(@(vX) conv(vX, vH, 'same'), ones(length(vX),1));

Generating Toeplitz Matrix which Matches the Convolution Shape Same

Using func2mat (Download), mH=func2mat(@(vX) conv(vX, vH, 'same'), ones(length(vX),1));

5 days ago | 0

Answered

Fast method to find average pairwise distance of a very large matrix?

I don't know about the mean distance, but the mean squared or root mean squared distance is pretty easy. Compare: A=rand(330000...

Fast method to find average pairwise distance of a very large matrix?

I don't know about the mean distance, but the mean squared or root mean squared distance is pretty easy. Compare: A=rand(330000...

8 days ago | 0

Answered

Creating a Random Upper Triangular Matrix with Unique Entries for Efficiently Computing Matrix Exponential.

Just use randi, e.g., >> k=8; M = triu(randi(10,k,k)) M = 9 10 5 7 3 5 8 10 0 10 ...

Creating a Random Upper Triangular Matrix with Unique Entries for Efficiently Computing Matrix Exponential.

Just use randi, e.g., >> k=8; M = triu(randi(10,k,k)) M = 9 10 5 7 3 5 8 10 0 10 ...

8 days ago | 0

Answered

How can I extrapolate the value for the slope of the line?

You could do, p=polyfit(log(x),log(y),1); slope=p(1);

How can I extrapolate the value for the slope of the line?

You could do, p=polyfit(log(x),log(y),1); slope=p(1);

8 days ago | 0

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