Risposto
Fitting an equation to a Sine Function with NonLinearModel.fit
"...I already tried using the "cftool" function in matlab but it did not have the equation I need...." Did you notice that yo...

oltre 6 anni fa | 0

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Risposto
How to replace last 3 digits in a floating point number by another 3 digits
format long x = -3.141592653589793; a = 287; x_new = sprintf('%.15f',x); x_new(end-2:end) = (sprintf('%d',a)); x_new = st...

oltre 6 anni fa | 0

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Risposto
I am trying to use ODE45, but I keep getting an error with myfcn saying I don't have enough inputs?
There are at least 4 problems in your code: 1. Split your main code and your ode function: tspan = [0 10]; f0 = [0 0]; ...

oltre 6 anni fa | 1

Risposto
Having trouble with ODE45 and a System of Ordinary Differential Equations
For every equation you have to input an initial condition. You have 8 but only give 2 initial conditions to ode45. Also your ...

oltre 6 anni fa | 0

Risposto
Is there a function to turn ?x2 matrix of coordinates of vertices of a polygon into a ?x4 matrix of coordinates of line segments of that polygon?
Yes, circshift will do the job: A = [2, 4; 5, 6; 6, 6; 8,5] B = [2, 4, 5, 6; 5, 6, 6, 6; 6, 6, 8, 5; 8, 5, 2, 4] % The sol...

oltre 6 anni fa | 0

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Risposto
could anyone help me to display the values in the matrix which are greater than the average value for the following code
B, C and D are not needed, if you use the inbuilt function mean: A=[3.3734 5.1245 4.3729 2.8406 6.5283 4.8144 ...

oltre 6 anni fa | 0

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Risposto
How can calcuate the lines of code efficiently?
Yes, you can if you avoid using a loop and vectorize your code - see here: tic %%%code nx=512; ny=nx; dx=1; dy=dx; format...

oltre 6 anni fa | 2

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Risposto
how can i differentiate a constant in simulink?
You already have done everything exactly correct - Simulink also did what is correct. What is the derivative of y(t)=3 with resp...

oltre 6 anni fa | 0

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Risposto
Eigenvalues and Eigenvectors of Symbolic Matrix
syms E t H = [E -t -t -t -t 0 0 0 0;-t E 0 0 0 -t -t 0 0;-t 0 E 0 0 0 0 -t -t;... -t 0 0 E 0 -t 0 -t 0; -t 0 0 0 E 0 -t 0...

oltre 6 anni fa | 0

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Risposto
what is wrong with my script
clear all for loop_index = 1:2 x = input('Input number to convert'); units = input('Input the units to convert from','s...

oltre 6 anni fa | 1

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Risposto
Any trick to name a variable with decimal number?
No, it is simply not allowed in Matlab. No way, no trick: https://de.mathworks.com/help/matlab/matlab_prog/variable-names.html#...

oltre 6 anni fa | 0

Risposto
PULL OUT A SPECIFIC WORD FROM A LONG STRING
You might want to start reading here: https://de.mathworks.com/help/matlab/matlab_prog/searching-and-replacing.html

oltre 6 anni fa | 1

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Risposto
How do I create a for loop to extract data from table?
No loop is needed: A = unstack(ReactionTime,'RESPONSE_TIME_ehmi','videostring') since you have invalid names for you video fil...

oltre 6 anni fa | 0

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Risposto
complement of an image
I = fliplr(imread('cameraman.tif')); I1 = triu((I),1); I2 = tril(imcomplement(I)); I_res = fliplr(I1+I2); imshow(I_res) B...

oltre 6 anni fa | 1

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Risposto
Trapz gives "Second and third argument must either be variables or a variable and a nonnegative integer specifying the number of differentiations."
syms x f_scalar = @(x) 5*x^2+3*x-4; g_scalar = @(x) -4*x^2+6*x+5; f = @(vec) arrayfun(f_scalar,vec); g = @(vec) arrayfun(g_sca...

oltre 6 anni fa | 0

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Risposto
Problem with input of ode113
I_1= pi^2; I_2= -2*pi^2; params.tau= 10; g= 0; V_1= -65; V_2= -65; state= [V_1;V_2]; I= [I_1;I_2]; options = odeset('ab...

oltre 6 anni fa | 0

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Risposto
How to define discrete variables in GA (genetic algorithm)
https://de.mathworks.com/matlabcentral/answers/401059-setup-discrete-values-for-decision-variables-in-optimization-problems

oltre 6 anni fa | 0

Risposto
Surrogate search with integer parameters
|*intcon*| was introduced to surrogateopt in R2019b. <https://de.mathworks.com/help/gads/release-notes.html>

oltre 6 anni fa | 0

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Risposto
Accessing value in a cell
Edited because of the comments: a = {'1,65,4,5'} b = str2num(a{:}) b(2)

oltre 6 anni fa | 1

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Risposto
Passing parameters in boundary value problem using BVP4C
See here: <https://de.mathworks.com/help/optim/ug/passing-extra-parameters.html |*passing extra parameters*|>. I suggest to eith...

oltre 6 anni fa | 0

Risposto
How to extract frames from a .mp4 video?
outputFolder1=('video'); v1=VideoReader('Clock.mp4'); vid1Frames=read(v1); for frame=1:size(vid1Frames,4) outputBaseFileNa...

oltre 6 anni fa | 0

Risposto
Plot pixels from 2D boolean array
% your array A = randi(2,101)-1; % the result; R=255*ones(101); G=255*(-A+1); B=255*(-A+1); res = cat(3,R,G,B); ...

oltre 6 anni fa | 0

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Risposto
Return a value from a table
Quarter = {'Q12019'; 'Q22019'; 'Q32019'; 'Q42019'; 'Q12020'; 'Q22020'; 'Q32020'; 'Q42020'}; QuarterStartDate = ['2019-01-01'; '...

oltre 6 anni fa | 1

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Risposto
Inserting vertical and horizontal line in bodeplot
xline and yline should work for this purpose. Both functions were introduced with R2018b. If you use an earlier release, just de...

oltre 6 anni fa | 2

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Risposto
Solving EOM coupled equations using ode45
syms x(t) y(t) eq(1)=diff(y,t,2)==(3/2)*(9.81*sin(y)-diff(x,t,2)*cos(y)); eq(2)=11*diff(x,t,2)+(1/2)*cos(y)*diff(y,t,2)-(1/2...

oltre 6 anni fa | 1

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Risposto
Array indices must be positive integers or logical values. Error in (line 8) mr(t)=mi-((mi-mf)*(t./tb));
I doubt you want t to have only one point. Also no for loop is needed: mi=2290000; mf=130000; tb=165; t=linspace(6.5,165...

oltre 6 anni fa | 1

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Risposto
could anyone help me how to combine data in two columns
Res = [A B]

oltre 6 anni fa | 0

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Risposto
Not able to use ode45 to solve and plot solution to vdp equation
You are missing some things. Looks like a mix of numeric and symbolic calculations, which won't work. But tou have luck - exactl...

oltre 6 anni fa | 0

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Risposto
How to divide column vector elements in unequal parts against a condition?
Due to different lengths of your daily data you should use a cell array: A = readmatrix('New Text Document.txt'); k_min = mi...

oltre 6 anni fa | 1

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Risposto
how to solve inequality in matlab R2016a
In 2019b this works by using an assumption: syms x real eqn = (x-1)*(x-2)*(x-3)*(x-4)> 0; S = solve(eqn, x) % Test solutio...

oltre 6 anni fa | 0

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