Answered
Fittype and fit do not work as expected (in a curve fitting)
x = [1 4 9 15 25 35 45 55 65 75 85 95 150 250 350 450 900]; y = [0 335 28 37 9 4 3.5 2 1 0.7 0.6 0.5 0.3 0.1 0.01 0.005 0.001];...

1 month ago | 2

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Answered
Newton Rapson method code question
Actually, this is surprisingly nice looking code. (A true compliment from me, given most of the student codes we see on here!) Y...

2 months ago | 1

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Answered
Converting an STL file to a 3D Surface/Equation
Um, I think you misunderstand a few things. It seems the STL model actually has thickness. So you have exported the entire thi...

2 months ago | 0

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I want the genetic algorithm to begin with intial parameter and this is not happened can you help me for making the genetic algorithm begin with the intial parameter?
I think you don't understand GA. It does not use a start point. It starts with an initial population of points from the sample s...

2 months ago | 0

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How do I convert a symbolic expression to a string?
Simple enough. Note the changes I made to your last line only. I could also have done it using character vectors, but then I wou...

2 months ago | 1

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Answered
Plotting a volume in 3D
Your question is somewhat incomplete, as to what you mean by plotting a solid volume. I'll assume you may mean something like th...

2 months ago | 0

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How to numerically calculate volume under the curve?
You have a surface. (Not a curve as I might say.) How do you compute the area under that surface? Simple. Just call trapz twice....

2 months ago | 1

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Answered
ode45 integration issues for some choices of physical parameters,
This is an absolutely classic case for a stiff system, where for some sets of system parmeters, you have two or more things happ...

2 months ago | 0

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How to choose 60 unique coordinates ('A') from 600 coordinates('B'), nearest to 60 other coordinates('C')
As I pointed out to @Voss and @Star Strider, if the points in B mst be unique, then there is an issue. If you simply choose the ...

2 months ago | 1

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finding variable of a given equation
gamma is a really bad choice of variable names, since gamma is itself a very useful function in MATLAB. Try to avoid doing these...

2 months ago | 1

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solving nonlinear equation using newton method
You just misunderstand how to use the exponential function. In MATLAB, e^x is written as exp(x). That makes your fn as: fn = @...

2 months ago | 0

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How to Set a Minimum Step Size for Variables in GA Solver (Global Optimization Toolbox)?
Really easy. Don't think of a step size for the GA solver. It does not take steps anyway, not like fmincon or other solvers of ...

2 months ago | 1

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Answered
Solution of system of nonlinear equations
This will be literally impossible to do in double precision, given the huge dynamic range of those coefficients. But we can look...

2 months ago | 0

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Support with interpolation using interp3 in MATLAB
And ... your question about MATLAB is? Far too much vague verbiage to know what is the problem. If you want to know how to use i...

2 months ago | 0

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Ode45 g and dg
You cannot use the variable dg4, before it is defined. And we see you do this: dg2=m*A+k*g(1)+h1*k*g(3)+dg4 ... dg4=h1*k2x*g(...

2 months ago | 1

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fitting with custom equation
(I assume you intended to write 1/y, and not I/y, where the variable I is not defined.) y = [1.6E5 2.5E5 4.1E5 8E5 1E6 2E6 7E6 ...

2 months ago | 1

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improve fit compared to R
x = [0.858734025700000 0.975248753121875 1.02525125312812 1.13140821289062 1.15927407430000 1.18768630564687 1.21665290240...

2 months ago | 1

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Some .jpeg photos can not be processed by Matlab code.
I've not even looked at your code. But you have jpg images, uint8 code values. So I wonder if adding the code values caused an o...

2 months ago | 0

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Finding concave hull around abstract shape
I don't know the soure of this data. But, can you start with the two pieces as separate entities, form polyshapes from each, and...

2 months ago | 1

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Numerical Integration MATLAB vs Python/VBA
This is difficult to say, because we know virtually nothing. First, does the problem arise from the use of subtly different da...

2 months ago | 0

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Warning: Explicit solution could not be found./ empty sym
Does an analytical solution exist for EVERY equation you can write down? (No.) Even if such a solution does exist, is it certain...

2 months ago | 0

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fmincon is not converge
It is very rarely easy to know why a solver fails to converge on a messy thing like this. But you should never let it come to th...

2 months ago | 0

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Is there any way to perform an at least partially symbolic smulation (using ODE or discrete model) in simulink?
Essentially, no. This is a frequent question about tools like ODE45 too. Simulink is a purely numerical tool, like ODE45 and oth...

2 months ago | 0

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d solve command matlab
syms e P S A t m V0 t0 V(t) real The point being that assumptions can apply only to variables, not functions. V(t) is a functio...

2 months ago | 0

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Plotting data dependent on three independent variables.
Do you have a 4-dimensional holographic monitor? That is, you can plot things in 3-dimensions. You will see a projection into a ...

2 months ago | 0

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vector output of a symbolic vector
syms s X Y Z l1 = X*s - 1 == 3*X + Y + Z + 2/s l2 =Y*s == - X - Y - 1/s^2 l3 =Z*s - 2 == X - Z - (s - 1)/s^2 [Xsol,Ysol,Zsol...

2 months ago | 0

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Optimisation of three function in two variables
There may be an issue here, if you think you can maximize them all simultaneously. The (x,y) coordinates that maximizes one func...

2 months ago | 1

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About fitting one curve with one equation and calculating two values from fitting
Suppose I gave you a set of data, and asked you to tell me two parameters from the data. All I need is one data point, More woul...

2 months ago | 0

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How to fit this model with a Weibull distribution?
If this is data that you think comes from a Weibull, then you do not want to use regression techniques to fit the distribution. ...

2 months ago | 0

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how i can show in matlab tha sqrt(x^2)=x in symbolic toolbox
Except, that equality does NOT hold! The sqrt "function" has two branches. sqrt(x^2) can as easily be -x, as it is x. So you can...

3 months ago | 1