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Problem with fitting a loglog plot
polyfit doesn't like the log of zero. One option is to remove the first row of the data: data_exp_high = load("data_Q_1e-8.txt...

6 mesi fa | 0

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Index in position 2 exceeds array bounds (Index must not exceed 1) errors?
N0 is a 4x1 vector, but you call it with two indices in the for loop! Turn N(1,j) into N(1) and similarly for the other calls t...

6 mesi fa | 0

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How do I solve this ODE system where there exists derivatives in both sides?
You can separate the terms as follows:

7 mesi fa | 0

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why am i getting grey figure box can someone fix please
Making some assumptions about your function pendulumODE, I think the following is more like what you expect to see: % Constants...

7 mesi fa | 0

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Algae growing, concentration curve problem
Increase nt to 10000 and it works just fine for T = 20000.

7 mesi fa | 0

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Error ''Array indices must be positive integers or logical values.'' when putting interval of 0.01 in a for loop
More like this: k = 0:0.1:2; n = numel(k); for i = 1:n x(i) = k(i); y(i) = k(i)*k(i) + 3*k(i) - 4; end plot(x,y...

7 mesi fa | 0

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Trying to code from Polymath
Like this for example (I'll leave you to extract the numerical values): Wspan = [0 2]; % Integration range % Initial valu...

7 mesi fa | 0

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Unable to solve differential equation with finite difference method
Should be more like this I think: b = 0.02; m = 80; L = 0.7; g = 9.81; J = m * L^2/3; a = 0; bet = 2; alpha = 0; beta = 3...

7 mesi fa | 0

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FDM using succsesive overrelaxation method,
For w1 and T1 you have w1(:,Nx1+1) = (((la*B1*dx1)/(dx2*A1))*(w2(:,2)-w2(:,1)))+w1(:,Nx1); %Continuity of shear stress ...

7 mesi fa | 0

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Solving first order ODE with initial conditions and symbolic function
You can do it numerically as follows: % input parameters Tinf=70+273.15; Ti=20+273.15; d=15e-2; r=d/2; cdepth=10/1100; Tf...

8 mesi fa | 0

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can someone help me to analyze this program? How does the flowchart look like?
Perhaps this will help: %radiasi benda hitam % constants h=6.626e-34; c=3e8; k=1.38066e-23; % range of values lambda ...

8 mesi fa | 0

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Error using surf (line 71) Data dimensions must agree
More like this? for it=1:2 for jt=1:3 zt(it,jt)=it+(jt-1); end end [x,y] = meshgrid(1:3,1:2); figure; surf(x...

8 mesi fa | 1

Risposto
How to find Basins of attraction for the Halley method?
Don'tforget the dot multiply: f = @(z) z.^3 +1; df = @(z) 3*z.^2; ddf=@(z) 6*z; % its roots r1 = -1; r2 = 1/2 + 1i*...

9 mesi fa | 0

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"Invalid use of operator." doesn't go even after trying various solutions :(
Why nor just use Matlab's inbuilt cart2pol function?

9 mesi fa | 0

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Heat equation using Boundary condition
function statements of this form (i.e. functions eq1, initial and ba) need to go at the end of the script, not the start.

10 mesi fa | 0

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A for loop that will run until a specific mathematical value is found
You could try replacing the "for i = 2:10 " loop by something like nports = 1; while Q(i)<Qdesired nports = nports ...

10 mesi fa | 0

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How do I use an "if" statement to determine the highest input value?
Try help if

10 mesi fa | 0

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How to plot all figures in only one plot?
Here's one simple way: x=-pi:0.1:pi; c=-6:5; figure hold on for i=1:length(c) y=c(i)*x.^(2)+4*x+2; plot(x,y) end...

11 mesi fa | 0

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Error in Hermite Polynomial
In line for j = 0:i-1 you have j starting at zero. Matlab's indices start at 1, so the following line should have X(j+1) not ...

11 mesi fa | 0

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Matlab code not computing
The use of square brackets in the scatter function is not the only problem! Are you looking for something like this? p=-1; z=...

circa un anno fa | 0

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how to plot the path of circular beam oscillation welding?
Like this? A=1; f=50; vf=0.02; time = linspace(0,100,500); x0 = vf*time; theta = 2*pi*f*time; x=A*cos(theta)+x0; y=A*sin...

circa un anno fa | 0

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how to change the direction of the airfoil
Change contourf(real(J),imag(J),imag(f),v2); %%%%% fill(real(zair),imag(zair),'k') to contourf(-real(J),imag(J),imag(f),v2);...

circa un anno fa | 0

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How to use 5 function coupled each other using ODE45? it is possible?
Better like this: MM0 = [10, 0, 0, 0, 0]; tspan = [0 100]; [t, MM] = ode15s(@mymode, tspan,MM0); M1 = MM(:,1); M2 = MM(:...

circa un anno fa | 0

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convert a column matrix with many rows into multiple column of equal rows
Try the reshape function.

circa un anno fa | 0

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"Not enough Imput arguments" ERROR
You haven't included J as an input argument to function Feedback_Ven_STEP.

circa un anno fa | 0

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Using polyfit in two arrays to detrend data.
polyfit just returns the coefficients of the polynomial. You need to use them in polyval to calculate data values.

circa un anno fa | 2

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Implicit solution using pdepe 1D advection diffusion reaction equation
I think you've overcomplicated the situation! Should be more like the following (which you should check very carefully, as I di...

circa un anno fa | 0

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I want to plot the vector field on F=x i+ j
Do you mean like this? [x,y] = meshgrid(-3:.15:3,-3:.15:3); Fx = x; Fy = ones(size(y)); %%%%%%%%%%% figure; quiver(x,y,Fx,F...

circa un anno fa | 0

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i have two set of data for temperature measurements which vary depends on each other. the variation may be divided into three portions. how can we seperate these portions
Here's a possible way (assumes the data is already in the workspace): dT2 = gradient(T2); minval = min(dT2(Time<2.5)); ix = f...

circa un anno fa | 0

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How to surf very small values keeping the same ratio?
Multiply them all by 1e4.

circa un anno fa | 0