how to store array
Try something like this — xv=1:5; for k = 1:numel(xv) x = xv(k); A=[5*x 0;2*x^2 1]; B=[0;2.55]; Y(:,x)=...

5 Tage ago | 0

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How to replace diagonal of square matrices within a cell array?
The easiest way is to subtract the diagonal of each matrix from the matrix — C = {rand(4); rand(4); rand(4)} Cr = cellfun...

6 Tage ago | 0

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How do I fit a gaussian to a bar plot and extract the variance of the gaussian?
One approach — x=[8,11,8,10,8,21,26,33,28,8,17,7,4,10,12]; y=1:15; [fitobject,gof]=fit(y',x','gauss1'); figure bar(y,x) ...

6 Tage ago | 0

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why my matlab didn't plot anything?
The plot call plots points here, so it is necessary to plot markers. The plot funciton draws lines between points, so its argum...

6 Tage ago | 1

How to extract certain values from text file to find average of the group of numbers?

6 Tage ago | 0

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Can only find one double angle formula of cos(2x).
Experiment with various options to get at least one more identity — syms x f(x) = cos(2*x) f1 = expand (f) f2 = rewrite(f,...

6 Tage ago | 0

ODE solver (45) giving two solutions (i.e. two plots) for an ODE! How do I plot only the one I need?
Use element-wise division H2= (k^2*(V+Y(:,3)+Y(:,4)))./(3-((k^2/2).*Y(:,2).^2)) ↑ ← HERE then ‘H2...

6 Tage ago | 1

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steady state responce of LTI system
Try this — A=[-0.0295 0.0478 0 -9.81;-0.1777 -1.4411 120 0;0.0005 -0.033 -1.5345 0;0 0 1 0] B=[0;-12.81;-6.59;0] C=[0 0 0 ...

6 Tage ago | 0

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How do I solve this error?
The value of ‘Ea’ in the exponential call makes the integral effectively zero of all the values of ‘V’. LD = load('V[1].mat...

7 Tage ago | 0

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adding each element of a matrix by previous elements of that row.
Try this — a = [1 2 3;4 5 6;7 8 9] acs = cumsum(a,2) b = acs ./ (1:size(a,2)) ratsb = rats(b) Experiment to get differ...

7 Tage ago | 1

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How do I only highlight the decreasing portion of the green in the plot with the find function?
The vector in the plot image (or the code to create it) are not available, so I substituted my own. This should get you star...

7 Tage ago | 0

Arrow of a vector ( r, theta) from a point (x,y).
One approach (using the quiver function) — x = rand y = rand r = rand theta = 30; ...

7 Tage ago | 2

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Label the actual data points in y-axis
One approach — x = linspace(0, 10, 5); yl = 250*(1-exp(-0.5*x)); [xr,yr] = stairs(x,yl/17); figure yyaxis left plot...

7 Tage ago | 1

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Creating a counter inside the ode45 function
See the ode45 documentation section on ODE with Time-Dependent Terms since that is most likely what you actually want to do. (I...

8 Tage ago | 0

How on earth to graph discrete time signals?
The only problems were in not using element-wise operations (use the ‘dot operator’ with the exponentiation an d multiplication ...

8 Tage ago | 0

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how to plot a contour plot with a csv file.
It depends what the data are. If they are a matrix of values, then use contour with the matrix. If they are random x and y v...

8 Tage ago | 0

Intersection between two functions
Try this slightly changed version of the existing code — f1=@(x) 2.2./sqrt(2*9.81*x); f2=@(x) tanh((3.5/(2*4.5))*sqrt(2*9.8...

8 Tage ago | 1

How do I plot a line against the y axis?
I am not certain what you want to do. Perhaps — x = linspace(0, 2*pi); y = sin(x); subplot(2,1,1) plot(x, y) grid yl...

8 Tage ago | 0

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How count a number of rows in a table (meteorologica data)?
I have no idea what you are actually doing. If you want to interpolate the rows in the table, consider converting it to a timet...

8 Tage ago | 0

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Extract data from cell array
Perhaps cell2mat would work. or alternatively, adding square brackets to concatenate the cell contents: L1 = [B{1,1}] L2 = [B...

8 Tage ago | 0

Replacing for loop in the function
See if ‘func2’ (without the loop) does what you want. f = @(x) exp(-0.1*x) .* sin(2*pi*x); a = -5; b = 5; n = 10; I...

8 Tage ago | 1

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Create a surface from several 1D plots
In the posted plot figures, note that the independent and dependent variable ranges are all different, even though all the plott...

8 Tage ago | 1

exponential curve fit coefficients
Linearising it by log-transforming the data is not appropriate, because that distorts the errors, making them multiplicative rat...

8 Tage ago | 1

How can I extract sub tables with unequally numbers of rows from main Table? Using loop or one code.
If you have specific criteria for how you want to extract the sub-tables, use logical indexing to extract specific rows. The ro...

9 Tage ago | 1

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why PSI values are diffrent when nlmefit using ode45 solver compared to when it uses analytical solution?
From the description, it appears that the code is attempting to fit data to the solution of a differential equation, or a system...

9 Tage ago | 0

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How to plot XRD data as 3D plot?
When I click on the link, I get a ‘DOI Not Found’ error. (EDIT — The new link is to an article behind a paywall, so I do not ha...

9 Tage ago | 1

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Struggling with solving a systems of equations
Try this — syms a_273 a_233 p_233 p_273 T_0 = 273; T_1 = 233; a_273 = 4.29E-3; p_233 = p_273 * (1 + a_273*(T_1 - T_0)) p_...

9 Tage ago | 0

Why I cannot get accurate curves using for loops?
It is not possible for me to run the posted code. With respect to the plots, perhaps using semilogx would work (instead of pl...

9 Tage ago | 0