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While solving a puzzle, I ended up having a complexity of T(n)=T(n-3)+T(n-5).
I was trying subtraction method. But I am unable to solve this. Please explain what should be the procedure.
This is a linear homogeneous difference equation with constant coeffs.. It is usually solved by transforming it to the complex plane and solving a polynomial.
Without a CS background (as you state), I'm afraid the details wouldn't fit in here. Start with the Wikipedia entry, if you're interested.
If you want to skip to the final solution, here is the Wolfram Alpha for it.
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Does Imagenet contain unlabeled examples like STL-10 dataset? because I see that the dataset is used for unsupervised learning but it seems to me it has only labeled examples.
You can parse the ImageNet data using ImageFolder in Pytorch. For unsupervised learning, simply don't account for the labels coming from the Dataloader
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This question is not about how to use matlab, but trying to find out what is happening when matab is solving a differential equation. Results are often different when using different numerical methods. i wonder which numerical method is used in matlab.
Matlab has all kinds of numerical solvers available. The basic set can be found at the bottom of this page:
https://www.mathworks.com/help/matlab/math/choose-an-ode-solver.html
If you'd like to know about a particular solver (say ode45) you can scroll to the bottom of the documentation for the given solver (for ode45 it's found here: https://www.mathworks.com/help/matlab/ref/ode45.html). For this solver the paper which explains it is linked. It may, however, be a little obtuse if you are unfamiliar with the general idea behind numerical solvers, so you might consider checking out a more pedagogical text in this area, such as the one at http://numerical.recipes/. You may also consider googling less complicated solvers like the Euler Method or the Runge-Kutta method -- both give you the flavor for how the numerical solvers work.
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Can I use this form when i need to solve system of ODE by ode45 on MATLAB
dy(3)=dy(1)*dy(2)+y(3)*y(2)
I mean is my expression correct?
For example how can I solve this:
dy(3)=dy(1)*dy(2)+y(1)
dy(2)=dy(1)-y(2)
dy(1)=dy(2)+dy(3)/y(1)
initial conditions are :
y(1)=1
y(2)=0
y(3)=0
MATLAB solves ordinary differential equations of the form dy/dt = f(t,y), your differential equation is fully implicit, of the form f(t,y,dy/dt) = 0. You can only solve it using ode15i. For more information, refer to the documentation on Ordinary Differential Equations and ode15i.
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I am new to image processing and am trying to learn few concepts by practically implementing certain functions. I heard about creating eigen images of an image, so tried to implement the same, to actually know what they are and what properties they alter.
Thus I obtained the eigen vectors using the eig function in matlab. How can I display these eigen images using the vector? Please forgive me if the question is wrong or rudimentary. Your help is much appreciated.
Assuming you have several images of size r x c, then taken the steps described on wikipedia, you should now have eigenvectors ev1, ev2 ... of length r x c.
If this is the case, it should be fairly easy to turn these into images again:
myImage1 = reshape(ev1,r,c);
Check whether r and c are in the right order and whether you need to transpose, but this is basically it.
For showing them you may want to look into surf or image.
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I have a function, dependant on a vector k=(x,y,z) and a function f(x,y,z)=0, I would like to find the solution space for (x,y,z).
Can this even be done analytically in matlab? I imagine it can be done numerically because my initial thought was to plot the surface created by this function, however this is of no use to me as I have 9 other constants in my equation with no numerical value assigned to them. Many thanks in advance for any help.
EDIT: This is for a polynomial degree 4.
There are no generic, analytical solvers for given function f(x,y,z) neither in matlab, nor in any other language. If such solution would exist, the Riemann hypothesis (and dozens others) would be solved ;)
For simple problems you could use symbolic math toolbox and a solve function:
http://www.mathworks.com/help/symbolic/solve.html
And obbiously there are numerical solvers, which you can use like vpasolve and others
http://www.mathworks.com/help/symbolic/vpasolve.html