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Alan Stevens


Last seen: Today
889 total contributions since 2020

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  • 12 Month Streak
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  • Knowledgeable Level 4
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Answered
must return a column vector
Do you want something like this sp=-0.5:0.5:14.5; for i = 1:length(sp) [t,y(:,i)]=ode45(@(t,y) phy_ode_1(t,y,sp(i)),0:0.5:1...

environ 6 heures ago | 1

Answered
Finding a range of data greater than 0.1
There must be a neater way, but the following might help: X = [ 0.02 0.17 0.32 0.28 0.04 -0.07 -0.01 -0.19 -0.45 ....

environ 7 heures ago | 0

| accepted

Answered
How to use ode45 with a time dependant second order differential equation
Turn your second order equation into two simultaneous first order equations.

1 jour ago | 0

Answered
how can i solve this problem with rk4 method?
If m=20, k=20, c=40 then function f should be f = -(c/m)*v - k/m f=@(t,x,v) -2*v -x; %dvdt

2 jours ago | 0

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Answered
How to solve a function with different ranges
Try C_ox = [16;15;7.5;2;7.5;15;15]; C_ox(C_ox<=15)=C_ox(C_ox<=15)/15; C_ox(C_ox>15)=1

3 jours ago | 0

Answered
how can i solve second order ODE with RK-4 without using a built in function in matlab?
This K11 = RK4(t(i), y1(:, i)); should be | K11 = RK4(t(i), y(:, i)); and this f12 = -3*y(1)+30*t+10; ...

4 jours ago | 0

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Answered
How to design the membership function in matlab?
How about the following for rule 3 (I'll leave you to invert for rule 4). x = [-180 -90 -89.001 89.001 90 180]; y = (x+180)/90...

7 jours ago | 0

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Answered
Help for plotting graph. Can someone help me?
In your while loop you don't update either nErrorsBitsW or nErrorsBitsInf so they always stay at 0, and never reach minNbits.

7 jours ago | 0

Answered
how I can insert these specific colours into my figures
Do you mean something like this? newcolors = [0 0.4470 0.7410; 0.8500 0.3250 0.0980; 0.9290 0.6940 0.1250...

9 jours ago | 1

Answered
Transpose x from a row vector to a column vector using the transpose operator. The program is prompting the x does not have correct values. the code i have entered is below
You probably meant x = [1:5]; % ie the ; is after the ] However, it seems to work ok for me as you wrote it!

9 jours ago | 0

Answered
Replace a entry of a table of Bisection Method for a specific term
Try using NaN or [ ];

9 jours ago | 0

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Answered
Plotting the intersection of a composition function
Do you mean something like this? Sfn = @(x) (x+1/4).*(x<=1/2) + (x+3/4).*(x>1/2); x = linspace(0,1,100); n=10; S = zeros(n,n...

19 jours ago | 0

Answered
Sun Synchronous with For Loop
When I run the program you've listed above it produces the graph you show!

19 jours ago | 0

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Answered
Integration of a function with variable parameter
Do you mean something like this? H = @(tau, lam, tt) lam./exp(tt-tau); T=50; step=1000; h=T/step; t=0:h:T; lambda = rand(1...

20 jours ago | 0

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Answered
How to get sinusodial behaviour from 2nd order ode using function handle?
You coud try implementing the function along these lines (obviously, you will need to use your own values for alpha etc): alpha...

21 jours ago | 0

Answered
How to find absolute maximum value of (x*(x-.25)*(x-.5)*(x-1))
You could just do something like gx = @(x) ((x.^4) -(1.75*x.^3)+(0.875*x.^2)-(0.125*x)); X = roots([4, -5.25, 1.75, -0.125]); ...

23 jours ago | 0

Answered
I want to see N,M first and then K,M in the same legend. I can see only N,M like the attached picture.
Do you mean like this? N = [10 20 30 40 50]; M = [1 2 3 4 5]; K=[1 3 5 6 7]; x = linspace(0, 1, 17); legendString = "N = " ...

23 jours ago | 0

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Answered
How to take integral with for loop?
Add the command I = sum(final); after the loop.

24 jours ago | 0

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Answered
Solving queue problem iterating through array
Try Lock19(Lock19~=-5)=0; Lock19(Lock19==-5)=3;

24 jours ago | 0

Answered
Sum of even numbers
Like so s = test(6); disp(s) function s = test(n) if n <= 0 %for n<= 0 the result would be 0 s = 0; els...

environ un mois ago | 0

Answered
Stopping ode45 when encountering errors and retrieving results
The following makes your example work. However, I suspect your real problem is more complicated. If so, you should upload it. ...

environ un mois ago | 0

Answered
After comma precision tracking for if statement
Here's one possibility a=85.0093792283283; b=85.0093791964294; a = floor(a*10^3); b = floor(b*10^3); if a==b disp('n...

environ un mois ago | 0

Answered
help me solve this if statement
Remove the ] in the top line! Then number = randi([0,9]) evens = [2,4,6,8]; odds = [1,3,5,7,9]; if ismember(number,evens) ...

environ un mois ago | 0

Answered
𝑦 = 2𝑐𝑜𝑠3𝑥
help plot

environ un mois ago | 0

Answered
Error: ode45 Must return a column vector?
Like this? % the total time domain response % System parameters k3 = 15; k1 = 10.0; k2 = 10.0; m1 = 2.0; m2 = 6.0; L = 1.0;...

environ un mois ago | 1

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Answered
How to solve following BVP ODE?
Weird ODE and initial boundary condition! You can solve for small values of x using the following (where y(x=0) was chosen by t...

environ un mois ago | 1

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Answered
Array indexes must be positive integers or logical values.
Looks like you are using SUM when you want sum. Change to: SUM= E1*sum(V(3:IOUT+1,JOUT+2)).... Also, in line 59, you should h...

environ un mois ago | 1

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Answered
How to get real solutions of a "system of nonlinear equations"?
If you are willing to do the differentiation by hand then the following works % L = 2*x^2 -2*x*y+y^3 + lambda*(x^2 + y^2 -4); ...

environ un mois ago | 0

Answered
Calling Euler Method to solve Shooting Method
You need to express your 2nd order ode as two 1st order odes y``(x) + 5y`(x) + 4y(x) = 1 v = dy/dx dv/dx = y``(x) So you h...

environ un mois ago | 0

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Answered
solving Diffrential equation one parameter related to another one
Like this? %% Input Parameters Rs = 200; Rr = 180; Phi = 180; t = 0:1:359; e = Rs - Rr; %% Calculation B = @(t) e*co...

environ un mois ago | 0

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