Physicist working in auroral physics, mostly on analysis of optical data, tomography-like inversions, ionospheric modeling.

Professional Interests: image processing

Answered

Vibration Analysis by using Fast Fourier Transform

Yes, go ahead and fft individual columns, for plotting it seems most likely you would plot the absolute of the fft, or possibly ...

Vibration Analysis by using Fast Fourier Transform

Yes, go ahead and fft individual columns, for plotting it seems most likely you would plot the absolute of the fft, or possibly ...

2 years ago | 1

Answered

[GUIDE] How to create scroll bar that moves the whole graph sideways?

If you look at the file exchange there seems to be several different submissions that does a range of different scrolling implem...

[GUIDE] How to create scroll bar that moves the whole graph sideways?

If you look at the file exchange there seems to be several different submissions that does a range of different scrolling implem...

2 years ago | 0

Answered

How can I make evenly distributed point on hemisphere mesh ?

There are a couple of submissions at the file exchange that deals with this type of problem. Maybe one of them will be good enou...

How can I make evenly distributed point on hemisphere mesh ?

There are a couple of submissions at the file exchange that deals with this type of problem. Maybe one of them will be good enou...

2 years ago | 0

Answered

how to install regtools package

That is(might be) a toolbox with a number of useful functions for solving and anlysing inverse problems, typically you should pu...

how to install regtools package

That is(might be) a toolbox with a number of useful functions for solving and anlysing inverse problems, typically you should pu...

2 years ago | 0

| accepted

Answered

Volumetric slice plot of tomographic data

If you change your colour-map from black-white to white-black then you might get some mileage out of experimentations with alpha...

Volumetric slice plot of tomographic data

If you change your colour-map from black-white to white-black then you might get some mileage out of experimentations with alpha...

2 years ago | 1

Answered

solving large number of simultaneous linear equations

If you simply use the standard numerical matrix capabilities of matlab something like this should be your solution: % I_L...

solving large number of simultaneous linear equations

If you simply use the standard numerical matrix capabilities of matlab something like this should be your solution: % I_L...

2 years ago | 0

Answered

how to use fractional Fourier transform on image in matlab

Perhaps as simple as using the 1-D fractional Fourier transform along either dimension? I found this on the file exchange: <htt...

how to use fractional Fourier transform on image in matlab

Perhaps as simple as using the 1-D fractional Fourier transform along either dimension? I found this on the file exchange: <htt...

2 years ago | 0

Answered

Can I model a 2nd order elliptical PDE using the PDE toolbox that has no BC for one of its edges?

Maybe I get this all wrong but to me it seems that what you implement in the FDM version is a Neumann BC with the gradient of th...

Can I model a 2nd order elliptical PDE using the PDE toolbox that has no BC for one of its edges?

Maybe I get this all wrong but to me it seems that what you implement in the FDM version is a Neumann BC with the gradient of th...

2 years ago | 0

Answered

fourier transform space dependent function

You shouldn't do the inverse Fourier transform element by element. The inverse Fourier transform should be calculated in the fre...

fourier transform space dependent function

You shouldn't do the inverse Fourier transform element by element. The inverse Fourier transform should be calculated in the fre...

2 years ago | 0

Answered

How to generate signal with seasonal and diurnal component?

Well a first stab would be to look at this as a function that has a daily variation, i.e. a time-period of 24 hours, and then pe...

How to generate signal with seasonal and diurnal component?

Well a first stab would be to look at this as a function that has a daily variation, i.e. a time-period of 24 hours, and then pe...

2 years ago | 0

| accepted

Answered

I have a discete probability distribution (histogram) and want to invoke rand to produce n random samples that follow the distribution specified by the histogram -how?

0, always start by looking for a solution at the file exchange. 1, I did a quick search and perhaps these submissions solves yo...

I have a discete probability distribution (histogram) and want to invoke rand to produce n random samples that follow the distribution specified by the histogram -how?

0, always start by looking for a solution at the file exchange. 1, I did a quick search and perhaps these submissions solves yo...

2 years ago | 0

Answered

Hi guys, I am working on Barrel distortion correction using MATLAB. I have written code as per correction algorithm. I am unable to mathematically compare corrected output with original image can you suggest me some parameter for it..

Well, if the only thing you have is the original image you cant really tell. You kind of have to trust the task-givers world tha...

Hi guys, I am working on Barrel distortion correction using MATLAB. I have written code as per correction algorithm. I am unable to mathematically compare corrected output with original image can you suggest me some parameter for it..

Well, if the only thing you have is the original image you cant really tell. You kind of have to trust the task-givers world tha...

2 years ago | 0

Answered

what must i do to bring a matlab program from Windows in ubuntu to work

Code contributer wasn't coding right for portability. Have a look at the documentation for fullfile and fileparts. Then set the ...

what must i do to bring a matlab program from Windows in ubuntu to work

Code contributer wasn't coding right for portability. Have a look at the documentation for fullfile and fileparts. Then set the ...

2 years ago | 0

Answered

random Distribution Points inside rectangle

Have a look at the documentation of rand. That function gives you uniformly distributed random numbers between 0 and 1 (have fo...

random Distribution Points inside rectangle

Have a look at the documentation of rand. That function gives you uniformly distributed random numbers between 0 and 1 (have fo...

2 years ago | 1

Answered

CT Raw Images Reconstruction code

Shouldn't that just be a minor geometric transformation between the angles to your detector and the angles to the flat detector...

CT Raw Images Reconstruction code

Shouldn't that just be a minor geometric transformation between the angles to your detector and the angles to the flat detector...

2 years ago | 0

Answered

Need to write a program that evaluates a postfix expression which is input by the user and then displays the answer.

If you want us to do your assignments you might have a better chance if you explicitly ask us to. What have you done so far? ...

Need to write a program that evaluates a postfix expression which is input by the user and then displays the answer.

If you want us to do your assignments you might have a better chance if you explicitly ask us to. What have you done so far? ...

2 years ago | 0

Answered

How can I plot spectrogram from discrete data?

Have a look at the documentation for the matlab function spectrogram: helpwin spectrogram From the question it seems t...

How can I plot spectrogram from discrete data?

Have a look at the documentation for the matlab function spectrogram: helpwin spectrogram From the question it seems t...

2 years ago | 0

Answered

Wrapping of cubic equation

Perhaps what you want is something like this: f_wrapped = rem(f,2*pi); HTH

Wrapping of cubic equation

Perhaps what you want is something like this: f_wrapped = rem(f,2*pi); HTH

2 years ago | 0

Answered

Unstable results using deconvlucy function

Without knowing exactly what your PSF looks like or is there are added noise to your delta-3D image, it is a bit difficult to gi...

Unstable results using deconvlucy function

Without knowing exactly what your PSF looks like or is there are added noise to your delta-3D image, it is a bit difficult to gi...

3 years ago | 0

Answered

Fit a custom function to data with errors in all dimensions (i.e. nonlinear total least square, deming, odrpack?)

Well if you want some tools for matlab they aren't too difficult to find: <https://se.mathworks.com/matlabcentral/fileexchange/...

Fit a custom function to data with errors in all dimensions (i.e. nonlinear total least square, deming, odrpack?)

Well if you want some tools for matlab they aren't too difficult to find: <https://se.mathworks.com/matlabcentral/fileexchange/...

3 years ago | 0

Answered

How do I have matlab extract the max value of a column within a moving range?

If you have the image processing toolbox you have access to the function: ordfilt2 as far as I understand your question ...

How do I have matlab extract the max value of a column within a moving range?

If you have the image processing toolbox you have access to the function: ordfilt2 as far as I understand your question ...

3 years ago | 0

Answered

how many methods to solve de in matlab?

Sure thing! <https://en.wikipedia.org/wiki/Numerical_methods_for_ordinary_differential_equations Wikipedias overview-article on ...

how many methods to solve de in matlab?

Sure thing! <https://en.wikipedia.org/wiki/Numerical_methods_for_ordinary_differential_equations Wikipedias overview-article on ...

3 years ago | 0

Answered

How can I show to column vectors side by side?

That should be as simple as: disp([[1;2;3],[6;4;1]]) HTH

How can I show to column vectors side by side?

That should be as simple as: disp([[1;2;3],[6;4;1]]) HTH

3 years ago | 0

Answered

solve any amount of systems of linear equations

Well, this sounds like a task from introduction to linear algebra, so have a read-up on over-determined problems, and under-dete...

solve any amount of systems of linear equations

Well, this sounds like a task from introduction to linear algebra, so have a read-up on over-determined problems, and under-dete...

3 years ago | 0

Answered

Image Normalization between range 0 - 1

It sounds like you need to ask your advisor what he wants. In my not necessarily humble opinion images ought to contain differen...

Image Normalization between range 0 - 1

It sounds like you need to ask your advisor what he wants. In my not necessarily humble opinion images ought to contain differen...

3 years ago | 1

Answered

fminsearch with vector function and vector output

For that function it is rather trivial, so you wouldn't need numerical methods. For a more general function f(x,a) it might ...

fminsearch with vector function and vector output

For that function it is rather trivial, so you wouldn't need numerical methods. For a more general function f(x,a) it might ...

3 years ago | 0

Answered

how can i determined the spectrum of potential for a finite well

Well, to me it sounds like homework on quantum mechanics, so my suggestion is that you read the relevant chapter. In case you ne...

how can i determined the spectrum of potential for a finite well

Well, to me it sounds like homework on quantum mechanics, so my suggestion is that you read the relevant chapter. In case you ne...

3 years ago | 0

Answered

What is best practice to determine if input is a figure or axes handle?

Simples, write those functions yourself, something along the lines: function OK = isfigure(h) if strcmp(get(h,'type'),...

What is best practice to determine if input is a figure or axes handle?

Simples, write those functions yourself, something along the lines: function OK = isfigure(h) if strcmp(get(h,'type'),...

3 years ago | 0

| accepted

Answered

My files are a mess, please help

In addition to the above answer I'd like to add a few more points. # you write functions for a couple of reasons, one of the ...

My files are a mess, please help

In addition to the above answer I'd like to add a few more points. # you write functions for a couple of reasons, one of the ...

3 years ago | 0

Answered

Plotting in GUI of Matlab

Keep the handles to the axes you create: axs(1) = subplot(1,2,1); axs(2) = subplot(1,2,2); Then make the axes you wan...

Plotting in GUI of Matlab

Keep the handles to the axes you create: axs(1) = subplot(1,2,1); axs(2) = subplot(1,2,2); Then make the axes you wan...

3 years ago | 0