How to plot streamlines continuously?
Not entirely sure what you mean. Changing startx and starty values? In your code you set the starting values on the y-axis to 0....

1 year ago | 1

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ode45 solver SIR model
Hi Ollie, to get the area under the curve, just add another integration variable that integrates over the curve, y(2), I called...

1 year ago | 1

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Extracting specific parts of an array
Assuming your variable is called data_velocity use something like: extractdata = data_velocity(data_velocity<0.1 & data_velocit...

1 year ago | 0

Simple For cycle (a small problem with the indexes)
There you go: omega_vet(1) = 55000; for i=1:length(phi_10(init:end)) x_ER_vet(i) = interp1(mass_flow_turbine_cor...

1 year ago | 1

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How can I get the first zero maximum in my program?
Georges, you could use something like this to find your first zero: b(find((abs(a)<1e-12),1)) Of course, this is assuming, for...

1 year ago | 0

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Displaying actual values from coded values for a for loop.
Wiktor, simply replace the is_leap_year(i) command with an if statement. Quick and dirty: if (strcmp(is_leap_year(i),'True')) ...

1 year ago | 0

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Hi Kris, syms y(x) Dy = diff(y,x,1); DDy = diff(y,x,2); ysol = dsolve(DDy + 3*Dy == 12*x - 5, y(0) == 1,Dy(0) == 0) fplo...

1 year ago | 0

Sorting array by datetimes does not work
Convert to and sort the table: T = sortrows(cell2table(HR_date_time_strings),2)

1 year ago | 0

Turning my function into an infinite loop
Hi Faris, instead of a for loop use a while loop with a condition like while abs(s_k - s_k1) > TolMax % here comes your co...

1 year ago | 0

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1 year ago | 1

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How do I change axes scale in a surface plot by a predefined factor?
Iron, if it just about changing the labels simply use xticklabels(). See the example below: x = linspace(-10,10,200); y = cos(...

1 year ago | 0

Error when opening a new figure
Hi Ran, in the error message it says that 'figue' is not recognized. There may be an 'r' missing (to make it 'figure'). If this ...

1 year ago | 0

How to use unique in a conditional statement nested in for loop?
Usman, you could do it this way. First compute all solutions in a matrix X and then compute unique values. n = 1000; for a = 1...

1 year ago | 0

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Failure in initial objective function evaluation. FSOLVE cannot continue.
Ahmed, use the following: fhandle = @Sample13; options = optimset('display','off','Algorithm','levenberg-marquardt'); a ...

1 year ago | 0

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Hourly and 6-hourly average of data in timeable
Phoebe, it looks like your data points are all equally spaced(?), 10 minutes. Check out the movmean() command.

1 year ago | 0

How to arrange correctly with a graph
Anton, add t as an input arg to: function y_out=rhs(t,y)

1 year ago | 1

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(FOR STEP RESPONSE GRAPHICS) how to make an inset of matlab figure inside the figure
Hi Dorukhan, add another axes() to the bottom of your code. E.g. p = get(gca, 'Position'); h = axes('Parent', gcf, 'Position'...

1 year ago | 0

Error in my ode45 equation.
Hi Zara, your vector of initial conditions has 5 components yo = [4 0 0 1 500.15]; however, you only have 4 differential equa...

1 year ago | 0

Error - matrix dimensions must agree
Hi Joe, I think this is what you are trying to do: x0 = 2; y0 = 2; x = [x0; y0]; iter = 0; max_iter = 100; tol = 0.001; ...

1 year ago | 0

Grid a plot with diagonal lines
There are a couple of things you could do. E.g. x = -5:1:5; N = numel(x); X = ones(N,1)*x; Y = X + X'; plot(X',Y'); grid

1 year ago | 0

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how to calculate the index of minimum value in each column cell array
Mohammad, use cell2mat() to convert the cell array to an ordinary array (e.g. A) and then use [val,loc] = min(A,[],1)

1 year ago | 1

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Graph can not show correct point
Hi Carey, ode45() picks its own time steps to do the integration. However, you can prescribe the times at which you want integra...

1 year ago | 0

how to plot to some maximum axis level?

1 year ago | 1

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Problem with plotting equation
Hi George, use fimplicit(): syms x y f(x,y) = log(y/x)-(sigma_e/sigma_a)*(log(1+x*sigma_a*tau*lambda_0/(h*c))-log(1+(x*sigma_a...

1 year ago | 0

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Error using symfun>validateArgNames (line 333) Second argument must be a scalar or vector of unique symbolic variables.
Hi Ahmed, almost there: syms x y y = symfun(x + exp(x),x); figure(1) fplot(y,[-13,13]) grid on In your code you declare x ...

1 year ago | 0

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how to get higher order derivative in ODE function
Hi Giacomo, when you solve the ODE this means you have solutions for y(t) and y'(t). You can then simply use the same equation f...

1 year ago | 0

How to solve "index exceeds the number of array elements"
Hi Ryan, try something like this: fl = 100; fu = 1500; % replace as necessary N = 100; f = linspace(fl,fu,N); cm = 0; f...

1 year ago | 1

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Fixing code to plot an ODE
Hi, you are almost there. This should get you started: hold on for n=1:200 p=.01*n; alpha=[.1; .5; .3]; beta=[....

1 year ago | 1

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