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How to loop through values?
Beta = linspace(0,1,10); Alpha = linspace(0,2,20); n = numel(Beta); m = numel(Alpha); Result = zeros(n,m); for i = 1:n ...

2 years ago | 0

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Using erfcinv and array indices are being rejected as not positive or valid, despite all being positive in the vector
As far as I understand, "erfbatp" is an array of numbers. So erfbatp(2*.05/2) = erfbatp(0.05) does not make sense, does it ? V...

2 years ago | 0

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Converting symbolic ODE solution to function ... Warnings
The solution is implicitly given by the equation (a*y+b*y^2/2+c*y^3/3+d*y^4/4)-(a*y0+b*y0^2/2+c*y0^3/3+d*y0^4/4) - integral_{x'...

2 years ago | 0

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convert the above expression into this graph
I'll show you how to solve for theta2 given theta from the equation sin(theta2-theta)+exp(-theta2/(omega*tau))*sin(theta)=0 F...

2 years ago | 1

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Trouble using ODE45 for coupled non-linear differential equation
I can't recover the four differential equations you solve from the two equations you included in mathematical form. Your equati...

2 years ago | 0

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How to get the answer from the following code. How can i extract the values from the code?
F = U1.y(5,1)-Nt*U1.yp(5,1) J = -1i*U1.y(6,1) N1 = -U1.y(7,1) N2 = -U1.y(8,1)

2 years ago | 0

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Explicit method for Allen-Cahn equation
xstart = -1.0; xend = 1.0; nx = 401; x = linspace(xstart,xend,nx).'; dx = x(2)-x(1); tstart = 0.0; tend = 1.0; nt = 10; ...

2 years ago | 0

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How to fill a variable with the results of an if...elseif statement
Use imin = 0; imax = 0; isaddlePts = 0; iinconcl = 0; for ind = 1:9 D=fxx(Xc(ind),Yc(ind))*fyy(Xc(ind),Yc(ind)) - (fx...

2 years ago | 0

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Need to rectify error in my matlab code given below
I want to get a plot of dn/dt versus t. syms t mu=2500*(10^-4); %cm^2*V^-1 * s^-1 R = 0.318; eta=377;% ohm N=3.681; %refind...

2 years ago | 0

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Using Runge Kutta to solve second-order differential equations with two degrees of freedom
I don't understand from your code if you want to perform a parameter study for 1000 different values of omega or if you want to ...

2 years ago | 0

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Cannot get fmincon to work
clear close clc format long %% Variables dp = 11.6; taup = 3710e-6; dn = 2; taun = 371e-6; Jl = 50e-3; ni = 9.696e9; ...

2 years ago | 1

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I continue to get this error and can't figure out how to fix it, Unable to perform assignment because the size of the left side is 1-by-4 and the size of the right side is 1-b
If you take the derivative of a polynomial, the degree of the resulting polynomial is one less than the degree of the original p...

2 years ago | 0

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coupled differntial equation using ode45
G = 1; Na = 1; xstart = -1; xend = 1; nx = 51; x = linspace(xstart,xend,nx); solinit = bvpinit(x, [0;0;1;0]); sol = bvp...

2 years ago | 1

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coupled differntial equation using ode45
syms y mu0 G Na U(y) T0(y) eqn1 = diff(mu0*diff(U,y)) == G; eqn2 = diff(T0,y,2) + Na*mu0*(diff(U,y))^2 == 0; conds1 = [U(-1)=...

2 years ago | 0

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Using tabular data for Curve fitting of function z = f (x, y) with incomplete values of z. These blank z (i, j) automatically takes zero values and this is a problem
green = [5 5 5 5 5 4 4 4 4 1 1 1]; blue = [5 10 15 20 25 5 10 15 20 5 10 15]; yellow = [455 322 261 205 169 410 306 246 191 25...

2 years ago | 1

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Numerical method of the "fimplicit" function
Since you can specify a mesh density in x- and y- direction, my guess is that the function is simply evaluated on X x Y. Sign ch...

2 years ago | 0

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My roots don't match example roots when solving routh criterion
syms K s p = s^3+9*s^2+12*s+15+3*K; solve(p,s,'MaxDegree',3) var2 = vpa(ans); var = subs(var2,K,-1)

2 years ago | 0

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Interrupt a while loop with functions if it takes too long
Is there a way of timing the iteration during its execution and break it? No. You could go into the function and time certain o...

2 years ago | 1

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How to solve the system of time dependent coupled PDE's?
ode23t seems to work for high Reynolds numbers. In case ode23t fails (e.g. for the low Reynolds number regime), I recommend the ...

2 years ago | 1

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Problem with my gamma_water values not giving me the correct pressure using fsolve
Look at the curves and see what's happening. Your first equation has two solutions while your second has none: DelH = -1* (-917...

2 years ago | 0

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An absolutely ascending sequence
x = 0:10; all(diff(x)>0)

2 years ago | 0

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Find zero of simple monotonic function where the independent variable can only be integer
If you know a lower integer value xl and an upper integer value xu with y(xl)*y(xu) < 0, you could do a binary search starting f...

2 years ago | 0

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Model simulation Code for SEIR
seir_simulation() function seir_simulation() % Parameters beta = 0.3; % Effective contact rate without control sigma = 1/5; ...

2 years ago | 0

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using loops and arrays to solve for variables in equations
You mean this ? x=zeros(5,1); vis=zeros(5,1); %strain rate epsUse=1e-14; Puse=1e9; PARAMS.R=8.314; %ideal gas constant %d...

2 years ago | 0

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How to use Matlab to find a pressure in a temperature and density spreadsheet using the nearest density value.
%Generate artificial data t = linspace(10,30, 25); p = linspace(1, 20, 20); [T,P] = ndgrid(t,p); d = exp(-((T-20).^2+(P-10)....

2 years ago | 0

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Kolmogorov-Smirnov (KS) Test
From the documentation: h = kstest(x,Name,Value) returns a test decision for the one-sample Kolmogorov-Smirnov test with additi...

2 years ago | 0

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Solving the hub location problem
You set % Renewal of population population = offspring; and offspring has only size 1x100 instead of 1x186. Thu...

2 years ago | 1

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Why does the value of tolerance stop at n=2 (third value of the iteration) within the while loop?
Maybe you mean tol = 1e-7 instead of tol = exp(-7) ? However: It's correct that MATLAB quits the while-loop after three val...

2 years ago | 1

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Minimization linprog constraint no feasible solution
The last equality constraint says that you want 0*x1 + 0*x2 + 0*x3 + 0*x4 + 0*x5 + 0*x6 + 0*x7 + 0*x8 = 6.6, thus 0 = 6.6 ... ...

2 years ago | 0

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4th order Runge Kutta Method Differential System
Note that COne and CTwo are given in muF - thus they should be prescribed as 1000e-6 in your code, I guess. COne = 1000e-6; C...

2 years ago | 0