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Error in newton (line 79) fitness=fit_fun(nucsh).I am always getting this error,What would be the reason?
I don't see the array "fitness" in "fit_fun" which you claim is the output of the function. Best wishes Torsten.

8 years ago | 0

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here is my codes and erors, I don't know what this erors mean ?
Seems you don't initialize the variable "Current_time_actual_load" before the if-condition (if isequal(idx,1)). Since idx do...

8 years ago | 0

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Obtain the analytic solution of a system of PDEs
There is no tool in MATLAB for the analytical solution of PDEs analogous to "dsolve" for ODEs. Best wishes Torsten.

8 years ago | 0

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How do I solve a second order ODE with boundary conditions?
Use "dsolve". Best wishes Torsten.

8 years ago | 0

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n th order derivative using forward difference
Recursively: https://ipfs.io/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/Difference_quotient.html Best wishes...

8 years ago | 0

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I have a homework assignment that I'm not sure how to do, the professor did not teach us anything about the matlab ode45 function. I have the line of code that I have so far but I'm not sure whats wrong.
function HW1Q3 clear; clc; t0 = 0; tf = 30; C0 = 0; soln = ode45(@f, [t0 tf], C0); t=linspace(0,tf,1...

8 years ago | 0

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How do I get the values of x at y=0.67 and y=0.87
x = (log(1/y))^(1/k)/p Best wishes Torsten.

8 years ago | 1

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Very basic calculations returning incorrect values
Use x^2 instead of square(x) (square is not what you expect it to be in MATLAB). Best wishes Torsten.

8 years ago | 1

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How do I express "a is a mutiple of b" constraint using intlinprog?
Replace the x_i by 100*y_i in your code. Best wishes Torsten.

8 years ago | 0

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In an assignment A(:) = B, the number of elements in A and B must be the same.
zz_dct_koeff(L+1:L+n) is a single value whereas V is a vector of length M*N. Thus the assignment zz_dct_koeff(L+1:L+n) ...

8 years ago | 1

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ODE45 function returning error for a system of differential equations
Use [t,y] = ode45( odefun, tspan, Y0 ) ; function dYdt = deriv(t,Y) Best wishes Torsten.

8 years ago | 0

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Please help me to overcome the error of the my code
I don't see variables i and k to define P{i,k}. Best wishes Torsten.

8 years ago | 0

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I have a problem with square bracket in solving ode45
function xprime = lorenz(t,x); alfa = 0.017; beta = 0.067; tau_e = 0.017; tau_l = 0.0001; tau_j =0.00000...

8 years ago | 1

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Make a function with vectors as variables
function result = f(a,x,d) result = a(1)*a(2)/(x(1)+x(2))*(x(3)+d(1)+d(2))^2; or simply f=@(a,x,d)a(1)*a(2)/(x(1)+x...

8 years ago | 1

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find minimum of spline fit based equation
Since you can evaluate a spline using "ppval", you can also find the minimum of your expression (using fminsearchbnd, e.g.). ...

8 years ago | 0

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How do I solve a single for temperature with one PDE containing dT/dx and dT/dt?
This is a partial differential equation for T. If [a;b] is the x-interval on which you want to solve the equation and a=x1<x2...

8 years ago | 0

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How to fix the "error using / matrix dimensions must agree"
V=(0.85*300)./A Best wishes Torsten.

8 years ago | 0

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How can I solve this differential equation using Finite Differential Method?
http://www4.ncsu.edu/~zhilin/TEACHING/MA402/chapter3.pdf Best wishes Torsten.

8 years ago | 1

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Bessel function summation from 1 to infinity
a_k = array of the first n zeros of J_0 J = besselj(1,a_k*alpha); J1 = besselj(1,a_k); summe = sum(J./J1); B...

8 years ago | 0

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How do I find the coordinates of a point of known distance from point on 3D plane in the direction perpindicular to the plane?
If A, B and C are the vectors with coordinates of the points A,B and C, then n = cross(B-A,C-A); n = n/norm(n); D1 = ...

8 years ago | 1

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How to plot for a different initial values at same time
zspan=[0 400]; v0mat = [1 0.01 0.12;2 0.01 0.12;3 0.01 0.12;4 0.01 0.12]; options=odeset('RelTol',1e-2,'AbsTol',1e-6,'Ev...

8 years ago | 0

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how to take vector and norm for indiviual column in the complex matrix
1) "for k=1:k" won't work ; you will have to use another variable name for the upper bound of the Loop. 2) You permanently ov...

8 years ago | 0

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boundary conditions with pdepe when m>0
Setting m=1 does not make your computation 2-dimensional, but calculations are done over the radius of a cylinder. You can't pre...

8 years ago | 0

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solving three non linear equation simultaneously??
As far as I can see, the equations are linear in the unknowns. So you only have to solve a system of linear equations using the ...

8 years ago | 0

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Can anyone help with writing an Euler solver code in MATLAB, that can solve any ordinary differential equation like ode1 inbuilt solver?
Convert your higher-order ODE into a system of first order ODEs: http://www.math.poly.edu/courses/ma2132/Notes/MA2132Equation...

8 years ago | 0

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How to set the range of the minimum and maximum values in a matrix or table data to another range
Divide your data by half their maximum value and subtract 1 to get your data in the range [-1:1]. Or divide your data by thei...

8 years ago | 0

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How to calculate this Sum :
yes, add the other term to the value of the telescoping sum. What's the problem ? In your case, your complete expression from...

8 years ago | 0

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could anyone tell me how to get the sum of an array to a fixed number say 12
a = 12*a/sum(a) if a is the array. Best wishes Torsten.

8 years ago | 0

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How to calculate this Sum :
Google "telescoping sum". Best wishes Torsten.

8 years ago | 0

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Could anyone help me to solve the issue in the following code
If you choose 40 numbers from the interval [0.01:0.09], they will at least sum to 40*0.01=0.4. But you chose the sum to be 0.35....

8 years ago | 0

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