fit 2nd order differential equation parameters to data
The problem appears to be not allowing the intial conditions to be estimated as parameters as well as the initial value of ‘a_m’...

5 days ago | 0

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Using solve to find intersection points
It’s as simple as it looks — syms x f(x) = exp(-x^2) g(x) = sym(0.8) xi = solve(f == g) xi_vpa = vpa(xi) .

5 days ago | 0

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How can I simplify the folllowing equation
One approach — syms x Eqn = 2*x^2 - 2*x*(2*x^2 - 1) + 2*x*(2*x*(2*x^2 - 1) - 2*x^2 + 1) - 1 Eqn = simplify(Eqn, 500) .

6 days ago | 0

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How to plot data with two different X- axis in a single plot?

6 days ago | 0

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translating and solving an equation with values of x and y known
In the third term, the square root is of the numerator only, not the entire expression, amd the denominator does not appear to h...

6 days ago | 0

To determine whether the system is stable.
Welcome to the wonderful world of floating-point approximation error! See ‘Check’ and ‘Check_max’ for an illustration of the ...

7 days ago | 1

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How to properly format a data table with fprintf?
In the numeric edit descriptors, the value to the left of the decimal is the field width (this includes all the numbers, the sig...

7 days ago | 0

Find which matrix row contains average minimum value
One approach — M = rand(288,365); AMV = mean(min(M)) % Average Minimum Value [val,idx] ...

7 days ago | 0

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trying to find theta
The Question lacks clarity. % plot mountain Mn_x = [0, 1000, 3014.8]; Mn_y = [0, 0, 616]; plot (Mn_x, Mn_y) hol...

7 days ago | 0

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Solve for x given y and plot
Depending on what you wan, either use fzero or interp1 — y = @(x) (2 * exp((2*x)/3)) - ((7*x.*exp((2*x)/3))/3); x = linspace(...

7 days ago | 0

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Doubt in solving ODE45
It seems that ‘dis’ does not appear anywhere. L=20; v=20;%v (m/sec) T=L/v; tspan_1=[0:0.001:T];%time range y0_1=[0;0];...

7 days ago | 0

How do you plot a line of constant value on a surface plot?
See if contour3 or contour3m will do what you want. [X,Y,Z] = peaks(30); figure surf(X,Y,Z) hold on contour3(X,Y,Z,[1 1...

7 days ago | 0

How to properly create function for integration?
There are several problems with the posted code image. First, ‘z’ is not defined anywhere, and it is not an argument to ‘E_fu...

7 days ago | 0

How can I plot the derivatives of the components of the solution to a system of ODEs?
The only way is to use al loop — tspan = [0 50]; z0=[0.01 0.01 0.01 0.01]; [t,z] = ode45(@(t,z) coupled(t,z), tspan, z0); ...

8 days ago | 2

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Cannot calculate integral function
If you want a numeric result, use vpaintegral (introduced in R2016b) instead of int. Not all expressions have analytic integral...

8 days ago | 0

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How to convert logarithmic to linear
If you have the Signal Processing Toolbox, use the db2mag function. If you do not have it: dB2mag = @(dB) 10.^(dB/20); ...

8 days ago | 0

Matlab Polar Plot Legend does not match with the plot
I cannot run that and I amm not certain what you are are plotting. Create a handle for each polarplot call: th = linspace(0, ...

8 days ago | 0

How to save output of double loop as a matrix?
Since ‘A’ is a matrix, save it as a cell array — for i=1:m for j=1:n A{i,j} = myfunction(...) end end .

8 days ago | 1

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There are NaN values in ‘x’, ‘y’, and ‘sd’. This ia frequent cause of patch failures. Remove them and it works! Try this ...

8 days ago | 1

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3D Sphere projection in Matlab
I worked on this for a while yesterday, without success. Today, I used a relatively straightforward approach that simply flips ...

8 days ago | 1

How would I go about writing this equation in matlabs?
There are several options, depending on what you want to do. syms x p(x) = 1/(2*sqrt(sym(pi)))*exp(-(x-5)^2/4) figure f...

9 days ago | 0

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How to save .mat file into hdf5 in matlab?
I have no recent experience with HDF5 files, however the h5write documentation for data indicates that it must be a numeric matr...

9 days ago | 0

Error with plotting my function
It works if you give ‘f’ a vector to work with — f = @(x) 2.^x-5*x+2; %Given Function xaxis = [0:0.5:2]; ...

9 days ago | 2

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I am trying to plot an ellipse using a polarplot function.
The polarplot function requires the angular measure to be in radians. Change that in the polarplot call and it works. (The e...

9 days ago | 0

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Am I using corrcoef correctly?
‘Am I using corrcoef correctly?’ Yes, except for squaring the result, and that will produce . H=log([0.01 0.02 0.03 0.04 ...

9 days ago | 0

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Converting a linear equation to decibel
The ‘theta’ vector likely needs to have more points, however that appears to be correct. I use a slightly different approach ...

9 days ago | 0

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Sampling frequency and correct signal plotting
I believe this is simply an interaction of the sampling frequency and the signal frequency, typically referred to as ‘aliasing’....

9 days ago | 0

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Creating new table from another table
There are several ways to do this, including using the findgroups function. A relatively efficient way is just to do the comp...

10 days ago | 1

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Amplitude detection in time series data
There are at least two functions you could experiment with, those being findchangepts and ischange. EDIT — (18 Sep 2021 at ...

10 days ago | 0

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