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Answered

How to solve Coupled Differential Equations

Try this — syms x(t) y(t) x0 y0 Dx = diff(x); Dy = diff(y); ode1 = Dy-Dx == 2 - x ode2 = 2-Dy - Dy == 3 + 2*y S = dsolve...

How to solve Coupled Differential Equations

Try this — syms x(t) y(t) x0 y0 Dx = diff(x); Dy = diff(y); ode1 = Dy-Dx == 2 - x ode2 = 2-Dy - Dy == 3 + 2*y S = dsolve...

ongeveer een uur ago | 0

Answered

How to interpolate a matrix ?

Try this — M=[ 3.2 5 4.1 4 5.6 3 6.7 ...

How to interpolate a matrix ?

Try this — M=[ 3.2 5 4.1 4 5.6 3 6.7 ...

ongeveer een uur ago | 0

| accepted

Answered

Vector counting syntax help?

Try this — A = [1 1 1 1 2 3 3 5 5 5 5 6 6 7]; [Au,~,ix] = unique(A,'stable'); Count = accumarray(ix,1); Result = table(Au(:...

Vector counting syntax help?

Try this — A = [1 1 1 1 2 3 3 5 5 5 5 6 6 7]; [Au,~,ix] = unique(A,'stable'); Count = accumarray(ix,1); Result = table(Au(:...

ongeveer 6 uur ago | 0

| accepted

Answered

How to get multiple variables in 'assume' ?

Declare them in the syms call as positive. MATLAB defines positive as values greater than 0. See the documentation section o...

How to get multiple variables in 'assume' ?

Declare them in the syms call as positive. MATLAB defines positive as values greater than 0. See the documentation section o...

ongeveer 7 uur ago | 0

| accepted

Answered

signal does not show filtered, using filter()

Use freqz to see what the filters are actually doing — Fs1 = 500; %Sampling Frequency ync = [.25, .5, .25]; ync1 = [-.085 ....

signal does not show filtered, using filter()

Use freqz to see what the filters are actually doing — Fs1 = 500; %Sampling Frequency ync = [.25, .5, .25]; ync1 = [-.085 ....

ongeveer 19 uur ago | 0

Answered

Trying to fit parameters for an ODE model to real data using lsqcurvefit

‘... I can't seem to find any real differences between the code I've constructed and that example.’ I agree that the initial ...

Trying to fit parameters for an ODE model to real data using lsqcurvefit

‘... I can't seem to find any real differences between the code I've constructed and that example.’ I agree that the initial ...

1 dag ago | 0

| accepted

Answered

how take a mathematical function from user

I would use the inputdlg function — prompt = {'Enter f(x,y):', 'Enter g(x):'}; response = inputdlg(prompt) f = str2func(['@(...

how take a mathematical function from user

I would use the inputdlg function — prompt = {'Enter f(x,y):', 'Enter g(x):'}; response = inputdlg(prompt) f = str2func(['@(...

1 dag ago | 0

Answered

Characteristics of a step response plot

Try something like this (using a transfer function from the documentation) — sys = tf([1 5 5],[1 1.65 5 6.5 2]); stinf = step...

Characteristics of a step response plot

Try something like this (using a transfer function from the documentation) — sys = tf([1 5 5],[1 1.65 5 6.5 2]); stinf = step...

1 dag ago | 0

Answered

I want to separate the signal from the noise with the help of a low pass filter.

I could not figure out which of those signals you want to filter, so I arbitrarily chose ‘t1’ and ‘y1’. They are not consiste...

I want to separate the signal from the noise with the help of a low pass filter.

I could not figure out which of those signals you want to filter, so I arbitrarily chose ‘t1’ and ‘y1’. They are not consiste...

1 dag ago | 0

Answered

How to change X axis in the form of percentage

Try something like this — x = linspace(77, 146); y = -60 - 15*sin(2*pi*x/50); figure plot(x, y) Ax = gca; xt = Ax.XTick...

How to change X axis in the form of percentage

Try something like this — x = linspace(77, 146); y = -60 - 15*sin(2*pi*x/50); figure plot(x, y) Ax = gca; xt = Ax.XTick...

1 dag ago | 1

Answered

Plotting a filter as a function of cyclic frequency using freqz()

Your approach is correct. The reason the freqz plot did not look correct is that you were passing the filtered signal to it, no...

Plotting a filter as a function of cyclic frequency using freqz()

Your approach is correct. The reason the freqz plot did not look correct is that you were passing the filtered signal to it, no...

1 dag ago | 0

| accepted

Answered

Coupled second order differential equation

Start by writing the equations using the Symbolic Math Toolbox. Specifically, see the documentation on the dsolve function. ...

Coupled second order differential equation

Start by writing the equations using the Symbolic Math Toolbox. Specifically, see the documentation on the dsolve function. ...

2 dagen ago | 0

Answered

ode45 not working

There are a few errors, all easily solved. Try this — m = 5; g = 9.81; r = 0.470; I = 0.37; ks = 0.012; dt = 0.01; ...

ode45 not working

There are a few errors, all easily solved. Try this — m = 5; g = 9.81; r = 0.470; I = 0.37; ks = 0.012; dt = 0.01; ...

2 dagen ago | 0

Answered

How to tell matlab that y is a function of x; not a constant

In the initial syms call, declare ‘y(x)’ instead of ‘y’ — syms x y(x) z z=x*y; Dz = diff(z,x) ...

How to tell matlab that y is a function of x; not a constant

In the initial syms call, declare ‘y(x)’ instead of ‘y’ — syms x y(x) z z=x*y; Dz = diff(z,x) ...

2 dagen ago | 1

| accepted

Answered

Locating rising peaks of variable amplitude pulses

I am not certain what you are doing, or what the ‘overlaid pulses situation’ means. There appears to be a significant amount ...

Locating rising peaks of variable amplitude pulses

I am not certain what you are doing, or what the ‘overlaid pulses situation’ means. There appears to be a significant amount ...

2 dagen ago | 0

Answered

How do I make a low-pass filter on this data set?

For an EKG, use the bandpass function with the lower cutoff at 1.5 Hz and the upper cutoff between 45 Hz (if there is mains or p...

How do I make a low-pass filter on this data set?

For an EKG, use the bandpass function with the lower cutoff at 1.5 Hz and the upper cutoff between 45 Hz (if there is mains or p...

3 dagen ago | 0

Answered

Adding text to each subplots

Use xlim and ylim to make the text positions relative to the axes — x1 = linspace(0,10, 25); y1 = exp(-0.1*x1); x2 = linspac...

Adding text to each subplots

Use xlim and ylim to make the text positions relative to the axes — x1 = linspace(0,10, 25); y1 = exp(-0.1*x1); x2 = linspac...

3 dagen ago | 0

| accepted

Answered

Error in App Designer " Undefined function 'sym2poly' for input arguments of type 'char'.."

Apart from the app code, apparently the numerator and denominator polynomials are not being transofmred into symbolic variables....

Error in App Designer " Undefined function 'sym2poly' for input arguments of type 'char'.."

Apart from the app code, apparently the numerator and denominator polynomials are not being transofmred into symbolic variables....

3 dagen ago | 1

| accepted

Answered

How to get tfest() to focus on a frequency range (or is something else wrong)?

Without any data or code, and since I have no idea how that was plotted, the only solution I can offer is to use the compare fun...

How to get tfest() to focus on a frequency range (or is something else wrong)?

Without any data or code, and since I have no idea how that was plotted, the only solution I can offer is to use the compare fun...

3 dagen ago | 0

Answered

CIplot unable to fill on log-x axis

I am not certain what you are doing. However in many situations, it is easier to initially plot in a linear scale, then afterwa...

CIplot unable to fill on log-x axis

I am not certain what you are doing. However in many situations, it is easier to initially plot in a linear scale, then afterwa...

3 dagen ago | 0

| accepted

Answered

Numerical integration using Trapz

That should produce one scalar value as ‘F’, so the subscripts are not necessary. I would do something like this — F = trap...

Numerical integration using Trapz

That should produce one scalar value as ‘F’, so the subscripts are not necessary. I would do something like this — F = trap...

3 dagen ago | 0

| accepted

Answered

Data is not importing? SOS

It is not importing because the correct approach to reading .wav files is to use audioread. Try that. It should do what you ...

Data is not importing? SOS

It is not importing because the correct approach to reading .wav files is to use audioread. Try that. It should do what you ...

3 dagen ago | 0

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,...

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,...

4 dagen ago | 0

Answered

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...

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...

4 dagen 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 ...

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 ...

4 dagen ago | 0

| accepted

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.

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.

4 dagen ago | 0

| accepted

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 =...

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 =...

4 dagen ago | 0

Answered

Calculating the Standard Deviation

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

Calculating the Standard Deviation

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

4 dagen ago | 0

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...

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...

4 dagen ago | 1

Answered

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...

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...

4 dagen ago | 1

| accepted