Answered
unable to solve with respect to y
Try this — syms s x y(x) y0 Dy0 C1 C2 Dy = diff(y); D2y = diff(Dy); ode=(x^2*D2y)-(3*x*Dy)+(3*y)==(2*x^4*(exp(x))) y(x,C1,...

5 years ago | 0

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What would be a best interpolation method to get test data for a specific temperature?
I would just use interp1 — TestData = sortrows(randi([0 200], 15, 4),1) InterpTemps = [0 40 100]; Interp_234 = interp1(TestD...

5 years ago | 0

Answered
xlsread isn't storing all the cell values from a column
Try something like this — T1 = readtable('YourExcelFile.xlsx', 'Range','A1:E19') That will import everything as a table, and ...

5 years ago | 0

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Answered
Output argument "K" (and maybe others) not assigned during call to "linear_kernel".
Why not just — K = dot(x1,x2) instead? See the documentation on the dot function for details.

5 years ago | 0

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Answered
The value of equation
I have absolutely no clue as to what you want. Try this — syms x u x3 %x = (0:1:4) L1 = 8; L =...

5 years ago | 0

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Calculating the Standard Deviation
Two options are to either calculate it directly, or use the normalize funciton — y = readmatrix('https://www.mathworks.com/mat...

5 years ago | 0

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Answered
How to Numerically Integrate Vector with Timestep
Use the trapz function (or cumtrapz, dependng on the result you want), The vector with respect to the numeric integration (time...

5 years ago | 1

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Getting the area of a surface integral from Matlab
See if simplifying it does what you want — syms phi the x = cos(phi).*sin(the); y = sin(phi).*sin(the); z = cos(the); dens...

5 years ago | 1

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Answered
How to process xlsx with readtable for graphs/plots
One approach is to use groupsummary to aggregate the data — T1 = readtable('https://www.mathworks.com/matlabcentral/answers/up...

5 years ago | 0

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Answered
Solve for one variable
It really is not at all different, except the format. Examing it — syms p A=0.1199; At=0.112; y=1.43; P1=119; Error =0...

5 years ago | 0

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Can you have lines between circles on a scatter plot?
Try this — a = [50:199]; b = [75:224]; i = [1:150]; scatter( i, [a;b] ) [ia,ib] = (ismember(a,b)); aidx = find(ia); hold...

5 years ago | 0

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Answered
empty sym: 0-by-1. please help me
a=9.61; b=0.16; fc=2000*10^6; c=300*10^6; A= 10^(1/10)-10^(20/10); B=(20*log10(4*pi*fc/c))+10^(20/10) syms R real; y=...

5 years ago | 1

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Answered
Help with Laplace ODE
Try this — syms t y(t) Y(s) Dy0 a b y0 Dy1 = diff(y,t,1); eqn = laplace(Dy1== a*sinh(a*t)) eqn = subs(eqn, {laplace(y(t), ...

5 years ago | 1

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Answered
FFT results correct for following filtering?
It is my code ( apparently copied from is the FFT right? ) and I do not see any mistakes in it! That signal and ‘CH0’ here ar...

5 years ago | 1

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Answered
Error in ode45 (line 115) and odearguments (line 90)
First, do not use global variables! Pass extra parameters as additional parameters. See Passing Extra Parameters for details....

5 years ago | 0

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Fourier series using matlab
We can’t correct it because you posted an image of it rather the actual code. The solution is straightforward nevertheless — ...

5 years ago | 1

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Convert signal from time domain to frequency domain with fft
If ‘T’ (that I assume is the time vector) is regularly-sampled (constant sampling intervals), first determine the sampling inter...

5 years ago | 0

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Answered
is the FFT right?
‘What is the meaning of the y axis?’ It is necessary to normalise the fft result by the length of the vector it uses as an ar...

5 years ago | 1

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Answered
Homogeneous differential equation with dsolve => Warning: Unable to find explicit solution.
The differential equation is nonlinear. There are only a few nonlinear differential equations that have analytical solutions. ...

5 years ago | 0

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Answered
how to draw a quadratic equation
It is definitely close to linear in the region you are plotting it. To plot it and see its quadratic shape, find the inflectio...

5 years ago | 0

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Solving linear system - but using only parts of the Matrix
The lsqr function is appropriate here — D = [... 0 0 0 0 0.345265357599750 0.457309520629080 0.548726230994530 0 0 0 0 0 0 0...

5 years ago | 1

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Answered
how to plot quadratic equation of 2 variable
One approach — syms x y=(-22916841.3/(2*250))*x.^2+5080.33*x+55 figure fplot(y,[-42 42]) grid .

5 years ago | 0

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Answered
Intersection between a 3D grid and flight path.
I am not exactly certain what you want. This will give the latitude and longitude grid intersections, computed using linear reg...

5 years ago | 0

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Solving multiple equations through an array
Displaay at all the solutions to understand what solve is doing — P = sym('P', [1 3]); V = sym('V', [1 3]); R_ON = [1 2 3]; ...

5 years ago | 0

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Answered
How do I multiply Sin and stepseq functions?
I have no idea what you are doing, and I had to look up ‘stepseq’, since I have never heard of it before. Experiment with thi...

5 years ago | 0

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Reading a time column
Here is one approach — Excel_Val = '16:50:13' % Original MATLAB_Val = re...

5 years ago | 0

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Answered
Best Matlab Editor replacement?
I’m not certain what you’re looking for in an Editor application. Several people on Answers like Notepad++. I downloaded it an...

5 years ago | 1

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Parameter estimation in a system of equation with curve fitting
Just after the declaration of ‘gum’, add — dxdt = zeros((18,1); so — function dxdt = gum(t,X) dxdt = zeros(18,1); ......

5 years ago | 1

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Answered
How to trim a surface intersecting with another
Try this— n = 50 ; x1 = linspace(1,10,n) ; y1 = linspace(-25,25,n) ; x2 = linspace(1,10,n) ; y2 = linspace(-10,10,n) ; ...

5 years ago | 0

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Answered
Estimate area inside point cloud
‘I have tried trapz(H,B), what results in a negative solution’ The data are still reliable. The negative solution is the res...

5 years ago | 1

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