Answered
Calculate the next 2 numbers in the sequence
u_(n+2) = 4*u_(n+1) + 2*u_n If you insert n = 0, you get u_2 = 4*u_1 + 2*u_0 So what is u_2 given that u_0 = 3 and u_1 = 2 ? ...

3 years ago | 0

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Answered
Trying to find the Euclidean distance of 2 vectors with different sizes
T =[5.1000 3.5000 6.4000 3.2000 5.4000 3.4000 5.7000 2.8000 5.7000 4.4000 5.6...

3 years ago | 0

Answered
Function for ODE45 requires all coefficients be written in it
tspan = linspace(0,35,35000); f0 = [1; 1; 1; 1; 1; 1; 1; 1]; a = 2; g_p = 3; g_s = 105; g_a = 0; g = 1; k = 250; P = 0; O_z = ...

3 years ago | 1

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Making a horizontal region between two functions
f = @(x) x.^3; g = @(x) x.^(1/3); a = 0; b = 1; hold on fplot(f,[a,b]) n = 20; for i = 1:n+1 start = [g((i-1)/n*b),1];...

3 years ago | 0

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Set initial condition to time different to 0
This is a boundary value problem, not an initial value problem. Thus you should use bvp4c instead of ode45.

3 years ago | 0

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Finding the minimizer using fminunc.
fv = @(x) x(1)^2 + x(1)*x(2) + (3/2)*x(2)^2 - 2*log(x(1)) - log(x(2)); [minimizer,minimum_value] = fminunc(fv,[1; 1])

3 years ago | 0

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Answered
I have one for time loop under which a caclulation taking place for a 1d domain (let say 1:n). I want to plot my data against 1d domain for all times.
for t=0:2:6 for i=1:n H(1+t/2,i) = something end end plot(1:n,H)

3 years ago | 0

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Testing if Data is close to the Exponential Distribution
How can I take this data and see if it is exponentially distributed? There is no way to do so. Also, how can I find how far t...

3 years ago | 1

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Answered
Nonlinear equations with two variables and a changing parameter
%The below is a system of nonlinear equations with two variables x, t, and %a changing parameter V. 0<x<0.2, t is around 6.3e6,...

3 years ago | 0

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Answered
Solving a system of equations using the solve function in a for loop?
Remove all the (t) in the symbolic variables, so use syms q TPCM Toil_PCM_to_EG instead of syms q(t) TPCM(t) Toil_PCM_to_EG(...

3 years ago | 1

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How to fit parameters of an ode by using ode45 and fmincon
Check your differential equations. As you can see, the derivatives for the given constellation (parameters and initial condition...

3 years ago | 1

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Answered
Solve Command giving wrong numbers for certain values, but gives perfect answers for the rest?
As you can see, there are two solutions for angle_3 and angle_4. Seems you took the wrong one for 290-330 degrees. syms angle_2...

3 years ago | 0

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3 state space model time discretization
x_dot = A*x + [B,C]*[u;v] So define A_ss = A, B_ss = [B,C]

3 years ago | 0

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Steady-state solution for system of parabolic PDEs?
Since this gives a system of second-order ODEs in general, the usual code to try would be "bvp4c".

3 years ago | 0

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Fitting curve of curve with parametric representation to measured data
opt = fmincon(@(S)Fehlerberechnung_Kreisevolvente(S(1),S(2),S(3),S(4)), [2,0,0,0]) instead of opt = fmincon(@(S)Fehlerberechnu...

3 years ago | 0

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Answered
When coding of function that shows error in yellow underline.
If f is a function handle, this line of your code doesn't make sense: if fc > f Only the result of function handles applie...

3 years ago | 0

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Getting A blank Graph
I changed y3 to what I think you meant. x=0:0.01:1; y1=(0.5*x.^5)-(0.6*x.^4)-(0.6*x.^3)+(0.3*x.^2)+0.25; y2=(sin(x).*cos(x))...

3 years ago | 1

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Answered
after runing this function, i only see the result of t{1}.. in the command window but not in the workplace so i can't use this value , does anyone know why?
Output T to the calling program - then it will appear in the workspace: D=[0 0 0 pi/2; 0 5 0 pi/6; 0 5 0 pi/2]; T = ...

3 years ago | 0

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Answered
Integration of elements of a matrix
syms x x1 x2 x3 x4 x5 x6 F3w F4w F5w F3p F4p F5p assume([x x1 x2 x3 x4 x5 x6 F3w F4w F5w F3p F4p F5p],'real') L2=60000; L1=4...

3 years ago | 0

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Solving Heat equation using pdepe does not give credible results
m=1; xmesh=linspace(0,270E-6,270); tspan=linspace(0,2,50); sol=pdepe(m,@pdefun,@icfun,@bcfun,xmesh,tspan); u=sol(:,:,1); fi...

3 years ago | 0

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Answered
Points inside the sphere
Hint: Use the function fun = @(x,y,z) ((x-X)/a).^2 + ((y-Y)/b).^2 + ((z-Z)/c).^2 - 1.0;

3 years ago | 1

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solving a system of equations
M1=3 P1=101325 %pa or 1 atm theta2 = .349 %rad or 20 degrees theta3 =.262 %rad or 15 degrees %first get P2 and P3 %area 2 ...

3 years ago | 0

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How can I plot two functions in the same graph?
fplot(@cosh) hold on p = @(x)0.6671*x.^3-1.7921*x.^2+2.7580*x-0.089; fplot(p) hold off

3 years ago | 0

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Answered
Iterating an equation through a range of values to satisfy a condition
count = 0; for X = 11:15 % Needs to be a range of values from 11 to 15 count = count + 1; X_array(count) = X; ...

3 years ago | 0

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Question on DDE23
lags=1; tspan=[0 10]; sol = dde23(@ddefunc,lags,[0.8; 0.2],tspan); plot(sol.x,sol.y(1,:)) function yp = ddefunc(~,y,Z) ...

3 years ago | 1

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Answered
solving 1D parabolic-elliptic equations with one initial condition
Supply an arbitrary initial condition for the elliptic pde - if possible one that satisfies its boundary conditions. If pdepe a...

3 years ago | 0

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How to solve multiple equation and get all value of the variable?
p1 can be chosen arbitrarily since the corresponding column in the matrix A is zero. (I set p1 = 1). Note that sol does not sa...

3 years ago | 0

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Answered
How can i plot this function? y=0.75/(log10(x)*2).^2
What do you mean by "in 2D" ? It is a simple function to be plotted y vs. x: x = 2:0.01:5; y = 0.75./(log10(x)*2).^2; plot(x,...

3 years ago | 0

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Mean distance function upgrade question
Don't know if you have enough RAM for this. Note that the distance matrix pdist2(group1,group2) will be 70000 x 80000 in your ca...

3 years ago | 1

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How would I use the 'count' function but to only count instances of both columns being specified?
x_y_= [1 4; 5 3;9 8; 2 7;1 8;7 2; 2 7;1 5;4 3]; n = nnz(ismember(x_y_,[2,7],'rows'))

3 years ago | 0