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Issue with numerical integration of two variable function
You created only function handles. So f(x,y) = ..... To compute the numerical value you need to assign numerical values to x an...

oltre 3 anni fa | 0

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Index in position 2 exceeds array bounds (must not exceed 2). Error in fun1 (line 5)
You calculate: for i=1:N for j=1:D pos(i,j)=lb(j)+rand*(ub(j)-lb(j)); end end with D= 2, so pos is a...

oltre 3 anni fa | 0

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How to Solve matrix equations in Matlab
Your method seems valid. But of course fsolve will only attempt to find a local solution, and it might get stuck in a place wher...

oltre 3 anni fa | 1

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Index exceeds the number of array elements
The argument in brackets should be an index number, so for example: x = 1:10; %a 1 x 10 vector for ix = 1:size(x,2); f(ix) = ...

oltre 3 anni fa | 0

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How to put fsolve in a loop, using 2 unknowns?
Replace the first line with: H = @(X)fsolve_root_finding(X(1),X(2));

oltre 3 anni fa | 0

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Need to apply trapezoidal rule for double integration with an array by using the for loop
There are two things that need correction: 1) Remove the line i=i+1. This is what the for loop does. (also don't use "i" in ge...

oltre 3 anni fa | 0

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Error in find Precision recall curve
Try without the quotations: [XCrit,tpr,YCrit,ppv] = perfcurve(Y,diffscore1,'HandGrip'); In general quotations are used to sp...

oltre 3 anni fa | 0

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I am solving a nonlinear Model predictive control problem . I get the following error. Can anybody help me understand the error report?
The error says that the derivative at the initial point (x0) is either NaN, infinity, or complex. So you should check whether th...

oltre 3 anni fa | 0

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time series interpolation of irregular data
You can use "griddedInterpolant". I would use 'pchip' as method.

oltre 3 anni fa | 0

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Multiple sample values into scatteredInterpolant
What works is: Make a 3D array from B, so: for ih=1:length(B) B_3D(:,:,id) = B{ib) end And then add a vector 'h...

oltre 3 anni fa | 0

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x undefined (Catenary Cable Case Study)
What you have done is programmed a function. So this function calculates fval when you give a value of x. You can now call this...

quasi 4 anni fa | 1

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Risposto
Locating point on x-axis where the slope is decreasing
Bascially you want to get the index when the change in theta becomes negative: dtheta = diff(theta); index = find(dtheta<0,1...

quasi 4 anni fa | 0

Risposto
Conversion to logical from sym is not possible.
g = 3; eff1=@(rr)-(1.8-0.8.*(1+rr)./(1-7.56.*g*rr))*rr/(0.01-0.11.*rr+0.06.*exp(23*rr)); x=fminbnd(eff1,-1,1); You could s...

quasi 4 anni fa | 0

Risposto
Hourly averages over a 20yr time series
Its not exactly clear over which values you want to calculate the mean, but have a look at this function, that can calculate mov...

quasi 4 anni fa | 0

Risposto
Removing/clearing NaN/0 values from matrix/array data
A1 = A(A~=0 & B~=0) should work

quasi 4 anni fa | 0

Domanda

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...

quasi 4 anni fa | 2 risposte | 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...

quasi 4 anni fa | 1

Domanda

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...

quasi 4 anni fa | 0 risposte | 0

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Domanda

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

oltre 5 anni fa | 0 risposte | 0

0

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Domanda

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...

oltre 5 anni fa | 1 risposta | 0

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Domanda

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 ...

quasi 6 anni fa | 0 risposte | 0

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Risposto
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...

quasi 6 anni fa | 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 ...

quasi 6 anni fa | 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...

quasi 9 anni fa | 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...

quasi 10 anni fa | 0

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Risposto
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

circa 12 anni fa | 0

Domanda

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...

circa 12 anni fa | 3 risposte | 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

circa 12 anni fa | 0

Domanda

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...

circa 12 anni fa | 4 risposte | 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 ...

circa 12 anni fa | 0