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Answered

how to find duration of peak; starting and ending points

Experiment with ths ischange function, and if you have the Signal Processing Toolbox, the findchangepts function.

how to find duration of peak; starting and ending points

Experiment with ths ischange function, and if you have the Signal Processing Toolbox, the findchangepts function.

ungefär 5 timmar ago | 0

Answered

Global optimization of parameters in ode

See: Is it possible to use Simulated Annealing or Genetic Algorithm for parameter estimation of a parametric System of ODEs? for...

Global optimization of parameters in ode

See: Is it possible to use Simulated Annealing or Genetic Algorithm for parameter estimation of a parametric System of ODEs? for...

ungefär 9 timmar ago | 0

Answered

Change color of graph at a certain value (temperature vs. time)

This eliminates the connections between the ‘gaps’ in the red and blue areas: D = load('Lade.mat'); Lade = D.Lade; Q1 = Lade...

Change color of graph at a certain value (temperature vs. time)

This eliminates the connections between the ‘gaps’ in the red and blue areas: D = load('Lade.mat'); Lade = D.Lade; Q1 = Lade...

ungefär 10 timmar ago | 0

Answered

Obtain single equation from a system of equations stored as an anonymous function

Not directly. I would do this: F = @(x) [x(1).*x(2).^2 + sin(x(2)) ; ... cos(x(1)) + x(2).^3 ] ; z = [2 6];...

Obtain single equation from a system of equations stored as an anonymous function

Not directly. I would do this: F = @(x) [x(1).*x(2).^2 + sin(x(2)) ; ... cos(x(1)) + x(2).^3 ] ; z = [2 6];...

ungefär 13 timmar ago | 0

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Answered

Error using @regress fuction

Try this: func = @(Q)regress(Q,X); then call it as: [b,bint] = func(Change1.ReturnsCleaned); (It seems a bit inefficient...

Error using @regress fuction

Try this: func = @(Q)regress(Q,X); then call it as: [b,bint] = func(Change1.ReturnsCleaned); (It seems a bit inefficient...

ungefär 14 timmar ago | 0

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Answered

MATLAB: solving a 2nd order ODE which has a parameter which evolves in time

Try this: syms k(t) y(t) % Declare ‘k(t)’ Here [System,Subs] = odeToVectorField(...

MATLAB: solving a 2nd order ODE which has a parameter which evolves in time

Try this: syms k(t) y(t) % Declare ‘k(t)’ Here [System,Subs] = odeToVectorField(...

ungefär 15 timmar ago | 0

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Answered

Overlap of 2 logicals

Since ‘B’ and ‘B2’ have not yeat appeared, try this with synthetic versions of them: B = randi([0 1], 5, 6) > 0 B2 = randi([0...

Overlap of 2 logicals

Since ‘B’ and ‘B2’ have not yeat appeared, try this with synthetic versions of them: B = randi([0 1], 5, 6) > 0 B2 = randi([0...

ungefär 16 timmar ago | 0

| accepted

Answered

How to make plot more visible in matlab

See the plot documentation section on Specify Line Width, Marker Size, and Marker Color. That should get you started.

How to make plot more visible in matlab

See the plot documentation section on Specify Line Width, Marker Size, and Marker Color. That should get you started.

ungefär 17 timmar ago | 0

Answered

Solve a second-order differential equation with constant parameters changing through an external parameter

It appears that what you want to do is to pass your data to your ODE function ‘fx’. See the documentation section on Passing Ex...

Solve a second-order differential equation with constant parameters changing through an external parameter

It appears that what you want to do is to pass your data to your ODE function ‘fx’. See the documentation section on Passing Ex...

ungefär 18 timmar ago | 2

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Answered

getting z transform in factored form?using Matlab?

Control System Toolbox: z = tf('z'); H = (4*z^2 + 3*z + 9) / (4*z^2 + 3*z - 4); zsys = zpk(H); Z = [zsys.Z{:}] P = [zsys.P...

getting z transform in factored form?using Matlab?

Control System Toolbox: z = tf('z'); H = (4*z^2 + 3*z + 9) / (4*z^2 + 3*z - 4); zsys = zpk(H); Z = [zsys.Z{:}] P = [zsys.P...

ungefär 18 timmar ago | 0

Answered

How do I use the "omitnan' option for the Mean function when calling the function using the splitapply function?

One option: splitapply(@(x)mean(x,'omitnan'),MyArray,G)

How do I use the "omitnan' option for the Mean function when calling the function using the splitapply function?

One option: splitapply(@(x)mean(x,'omitnan'),MyArray,G)

en dag ago | 0

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Answered

Print figure without its title

One option is to keep the title in the figure call. See Specify Figure Title for an example. Another option is: title('Ran...

Print figure without its title

One option is to keep the title in the figure call. See Specify Figure Title for an example. Another option is: title('Ran...

en dag ago | 0

Answered

Error calling a function or indexing a variable, apparently the first line for plotting is wrong, can't figure out whats wrong with it...

The ‘error’ function needs to be defined as an anonymous function, and ‘y’ needs to be the same size as ‘c’. Try this: erro...

Error calling a function or indexing a variable, apparently the first line for plotting is wrong, can't figure out whats wrong with it...

The ‘error’ function needs to be defined as an anonymous function, and ‘y’ needs to be the same size as ‘c’. Try this: erro...

en dag ago | 0

Answered

plotting a polinomial fraction over a strict range

I do not have the DSP System Toolbox, so I do not have tfplot. Try this instead: q=[1 1]; d=[1 1 1]; x=0:0.001:3; trf ...

plotting a polinomial fraction over a strict range

I do not have the DSP System Toolbox, so I do not have tfplot. Try this instead: q=[1 1]; d=[1 1 1]; x=0:0.001:3; trf ...

en dag ago | 0

Answered

Finding points with same y-value on a graph.

Try this: x = [2,4,7,9,10,14]; y = [5,10,15,14,12,3]; new_y_value = 12.5 [~,idx] = max(y); newx(1) = interp1(y(1:idx), x(...

Finding points with same y-value on a graph.

Try this: x = [2,4,7,9,10,14]; y = [5,10,15,14,12,3]; new_y_value = 12.5 [~,idx] = max(y); newx(1) = interp1(y(1:idx), x(...

en dag ago | 0

Answered

I want to do the correlation of the following two plots

Going back to using my code (because it is easier to work with): Ts=1/200e6; t=Ts:Ts:0.00005; y=[ones(1,2000) zeros(1,8000...

I want to do the correlation of the following two plots

Going back to using my code (because it is easier to work with): Ts=1/200e6; t=Ts:Ts:0.00005; y=[ones(1,2000) zeros(1,8000...

en dag ago | 1

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Answered

system of 3 equation with 3 unknown, with two 2nd order equation

The resuillts are strictly numerical (not containing symbolic variables), so use vpasolve instead of solve: syms QV3 QV2 QVl ...

system of 3 equation with 3 unknown, with two 2nd order equation

The resuillts are strictly numerical (not containing symbolic variables), so use vpasolve instead of solve: syms QV3 QV2 QVl ...

en dag ago | 0

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Answered

how to solve this complex equation in matlab?

Try this: syms theta gama Eqn = exp(pi/4*i)*(5+15i)+exp(i*theta)*(25+5i) == 40+exp(i*gama)*(-10+20i); [theta,gama] = vpasol...

how to solve this complex equation in matlab?

Try this: syms theta gama Eqn = exp(pi/4*i)*(5+15i)+exp(i*theta)*(25+5i) == 40+exp(i*gama)*(-10+20i); [theta,gama] = vpasol...

2 dagar ago | 0

Answered

removing all rows with duplicate information in two columns

Try this: a=[1 2 3 4 5; 1 3 4 5 6; 1 2 3 5 5]; [~,~,idx] = unique(a(:,[1 5]),'rows'); tally = accumarray(idx,(1:numel(idx))....

removing all rows with duplicate information in two columns

Try this: a=[1 2 3 4 5; 1 3 4 5 6; 1 2 3 5 5]; [~,~,idx] = unique(a(:,[1 5]),'rows'); tally = accumarray(idx,(1:numel(idx))....

2 dagar ago | 0

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Answered

How can I separate the arrays when making a table?

Try this: n = 5; A = rand(n,1); B = rand(n,5); T = array2table([A, B]) That should do what you want.

How can I separate the arrays when making a table?

Try this: n = 5; A = rand(n,1); B = rand(n,5); T = array2table([A, B]) That should do what you want.

2 dagar ago | 1

| accepted

Answered

how to combine date and time

In theory at least, datetime should be able to do this seamlessly using the timeofday function for the seconds. In practice, it...

how to combine date and time

In theory at least, datetime should be able to do this seamlessly using the timeofday function for the seconds. In practice, it...

3 dagar ago | 0

Answered

What am I doing wrong? Matrix operators

If you want to raaise the elements of a matrix to a power, use element-wise exponentiation with the dot operator: .^ and see: Ar...

What am I doing wrong? Matrix operators

If you want to raaise the elements of a matrix to a power, use element-wise exponentiation with the dot operator: .^ and see: Ar...

3 dagar ago | 0

Answered

I can't plot a function I created with respect for time

You need to code it as an anonymous function. See Anonymous Functions for details. Specifically: x = @(t) X.*(exp(-Zeta.*...

I can't plot a function I created with respect for time

You need to code it as an anonymous function. See Anonymous Functions for details. Specifically: x = @(t) X.*(exp(-Zeta.*...

3 dagar ago | 0

Answered

Error when solving system of equations with ode45 in MATLAB R2019b

The system contains only two derivatives, and . It appears that ‘u’ and ‘z’ are either functions that need to be evaluated, or...

Error when solving system of equations with ode45 in MATLAB R2019b

The system contains only two derivatives, and . It appears that ‘u’ and ‘z’ are either functions that need to be evaluated, or...

3 dagar ago | 0

Answered

How to plot a function that relies on another function?

Since ‘A’ is a function, it must be evaluated in order to use its results. Try this: A = @(y) y*2; X = @(y) A(y)+10; f...

How to plot a function that relies on another function?

Since ‘A’ is a function, it must be evaluated in order to use its results. Try this: A = @(y) y*2; X = @(y) A(y)+10; f...

3 dagar ago | 0

| accepted

Answered

How to make this signal linear

If you want to eliminate the low-frequency parabolic(?) trend, the easiest way is to use a digital filter: signal_2 = load('si...

How to make this signal linear

If you want to eliminate the low-frequency parabolic(?) trend, the easiest way is to use a digital filter: signal_2 = load('si...

5 dagar ago | 0

| accepted

Answered

Designing IIR Butterworth filter (pass band)

Yes. Just define the order as 5. There are different design functions in the Signal Processing Toolbox (butter that I have a...

Designing IIR Butterworth filter (pass band)

Yes. Just define the order as 5. There are different design functions in the Signal Processing Toolbox (butter that I have a...

5 dagar ago | 0

Answered

Play 2 wav files after each other

Use the playblocking function to get them to play the way you want them. [y1, Fs1] = audioread('file1.wav'); %this file i...

Play 2 wav files after each other

Use the playblocking function to get them to play the way you want them. [y1, Fs1] = audioread('file1.wav'); %this file i...

6 dagar ago | 1

Answered

I have a function which is ranged from 0 microseconds to 50 microseconds. I just want to plot its exact copies from 0to50 microsecond,50 to 100microseconds,100 to 150 and so on

Try this: Ts=1/200e6; t=Ts:Ts:0.00005; y=[ones(1,2000) zeros(1,8000)]; x=sin(1256e6*t + 2198e10*t.^2); z=x.^y; NR = ...

I have a function which is ranged from 0 microseconds to 50 microseconds. I just want to plot its exact copies from 0to50 microsecond,50 to 100microseconds,100 to 150 and so on

Try this: Ts=1/200e6; t=Ts:Ts:0.00005; y=[ones(1,2000) zeros(1,8000)]; x=sin(1256e6*t + 2198e10*t.^2); z=x.^y; NR = ...

6 dagar ago | 1

| accepted