Question


1 iteration in fsolve: new x and no more
I want to use fsolve to only use one iteration: get the Jacobian, get x1 and done. However when test the code below, which tries...

9 Monate ago | 2 answers | 0

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Optimization of system ODE
It is still not clear what your problem is. Do you get an error? Do you get a different solution than you expected? Anyway f...

11 Monate ago | 1

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Why is EACH function evaluation inside a parfor loop much faster then ONE evaluation outside the loop?
Basically I calculate a finite difference Jacobian of a function, as shown below. The function evaluation labelled SINGLE RUN t...

11 Monate ago | 0 answers | 0

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Question


Second Order optimality fmincon
Someone explained the second order condition for optimality of a constrained optimization problem here: https://math.stackexch...

mehr als 2 Jahre ago | 0 answers | 0

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Incorrect solution for symmetric problems in fmincon
If I maximize XX(1)^2+XX(2)^2 subject to x1 + x2 <=1 and use starting value X0=[0.5,0.5] I get as solution X=[0.5,0.5], although...

mehr als 2 Jahre ago | 1 answer | 0

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Question


patternsearch with nonlinear equality constraint: any advice for more efficient steps?
Dear all, I have a constrained optimization problem which is not differentiable (because of some random errors), but it should ...

fast 3 Jahre ago | 0 answers | 0

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How to normalize curves with multiple peaks such that each peak will be 1 and each valley will be 0?
Yeah, you would have to calculate a scaling factor for each peak/trough. In one dimension you can then use the scaling factor fo...

fast 3 Jahre ago | 0

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Tangent at a given point to a nonlinear curve
I think you need to be a bit more precise in what you want: you have data with errors in them, and you want to fit a curve that ...

fast 3 Jahre ago | 0

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Matlab R2014A blurry on high-dpi windows device
Two things did it for me: 1. go to matlab/bin and right click application, choose compatibility and check "disable scaling on h...

fast 6 Jahre ago | 0

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fmincon and exitflag = -2 or 2 / non respect of constrained conditions
getting exit message 2 is not bad but if you insist on having 1, you could try to use smaller values for TolX (ie.. 1e-10 or eve...

fast 7 Jahre ago | 0

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Why does the first value in loop get overwritten
Thanks guys... normally i never save iteration variables like 'fi' but in this case the files contained "fi = 1". very silly

fast 9 Jahre ago | 0

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Why does the first value in loop get overwritten
For some reason when fi == 1, NPV_list(1,1) is inserted correctly, but when fi=2 the value gets overwritten, which i dont unders...

fast 9 Jahre ago | 3 answers | 0

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Vectorize sum of discount rates
thank you all for you answers... all did what i wanted, but the one by Matt Fig is the most simple

etwa 9 Jahre ago | 0

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Vectorize sum of discount rates
Hi, I want to vectorize the calculation of series like this: [R^0;R^0+R^1;R^0+R^1+R^2;...etc. Im quite sure this should b...

etwa 9 Jahre ago | 4 answers | 0

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sum elements of matrix if...
It seems i can not edit my comment... so here again (sorry for mess, but i forgot to 'code' my code) Ok, i was not clear let ...

etwa 9 Jahre ago | 0

Question


sum elements of matrix if...
Hi, lets say i have two matrices: A=rand(5,10); B=[ones(1,10);3*ones(1,10);ones(1,10);ones(1,10);3*ones(1,10)]; I...

etwa 9 Jahre ago | 2 answers | 0

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fixed-point iteration for root finding
a while loop might be a good idea: err_lim = 1e-6; x_new = %initial guess err = err_lim *2; %arbitrary to pass while ...

mehr als 9 Jahre ago | 0

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how to solve a system of equations with n equation and m unknown (m>n)?
i think fmincon (constrained optimization) will work best... if you try to minimize some error use as the objective: objective=e...

mehr als 9 Jahre ago | 0

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How to stop nonlinear fitting and obtain the results of fitting at that iteration
the display iter only displays something after an iteration is complete (after all function evaluations of that iteration are do...

mehr als 9 Jahre ago | 0

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How to stop nonlinear fitting and obtain the results of fitting at that iteration
im no expert on this (sorry) but did you try the 'output' function thingy... i know for most optimizers there is such a thing. i...

mehr als 9 Jahre ago | 0

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what is the optimal way to build a sparse matrix from row/col index, and value data?
did you check 'sparse'? i think this will do what you want: S = sparse(i,j,s) where i,j,s are your 3 column vectors... htt...

mehr als 9 Jahre ago | 0

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Optimization: Which algorithms I should choose when it's difficult to define an objective function?
...and if your problem is continuous, then the other optimizers are more usefull (fminsearch, fminunc, fsolve, fmincon,...). ...

mehr als 9 Jahre ago | 0

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how can i remove this error in matlab?
ermm, what error? and what do you actually want the line to achieve? i mean, the code wants to assign a matrix with blanks to co...

mehr als 9 Jahre ago | 0

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Problem using 'deal' for objective and gradient in comb. with 'DerivativeCheck'
When using optimization tools I usually keep my objective function and gradient function as separate subfunctions and then use '...

mehr als 9 Jahre ago | 1 answer | 0

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The problem in fminsearch function error
i dont know what you want this to do: x = sym(zeros(6,1)); for i=1:1:6 x(i) = sym(sprintf('x%d',i)); end or: ...

mehr als 9 Jahre ago | 0

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Calculating stationary distribution of Markov chain
I am calculating the stationary distribution of a Markov chain. The transition matrix P is sparse (at most 4 entries in every co...

mehr als 9 Jahre ago | 2 answers | 1

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Question


me not like new lay out of this section! (not a question)
i dislike the new lay out of this section, because now only 2 or 3 questions fit on my screen, ie. any overview is lacking and i...

mehr als 9 Jahre ago | 2 answers | 2

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problem with dynamic optimization solution when increasing the scaling parameter value of the objective function
What is your utility function and how do you scale it? And is zero also your starting value for the controls? The only thing...

mehr als 9 Jahre ago | 0

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Question about fsolve
first you should try yourself to solve the equation when there is just 1 line (1 a and a_1). see what's happening... and then in...

mehr als 9 Jahre ago | 0

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Answered
Vectorizing finding indexes
Hmmmmm, andrei and jamie: do your solutions only work when Y consists of integers??? In my example Y was just integers, but in f...

mehr als 9 Jahre ago | 0

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