11,984 total contributions since 2012

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Answered

Condition for matlab if

I suspect that here: PP=Wscat((g(i)-50:g(i)),i) ; % Error Subscript indices must either be real positive integers or logicals...

Condition for matlab if

I suspect that here: PP=Wscat((g(i)-50:g(i)),i) ; % Error Subscript indices must either be real positive integers or logicals...

4 hours ago | 0

Answered

Contourf isoline in logarictmic scale

Plotting it as: contourf(log(abs(Z))) or: contourf(log10(abs(Z))) is likely the only option. The problem is that the cont...

Contourf isoline in logarictmic scale

Plotting it as: contourf(log(abs(Z))) or: contourf(log10(abs(Z))) is likely the only option. The problem is that the cont...

5 hours ago | 0

Answered

hourly mean - why do I get the following error

The problem may be that you’re running your code in the Command Window. When I run it in a script, it runs without error and ...

hourly mean - why do I get the following error

The problem may be that you’re running your code in the Command Window. When I run it in a script, it runs without error and ...

15 hours ago | 0

Answered

can you write a vector function?

You pretty much wrote it yourself: x = @(u,v) [2-v.*sin(u/2).*sin(u); 2-v.*sin(u/2).*cos(u); v.*cos(u/2)]; See the documenta...

can you write a vector function?

You pretty much wrote it yourself: x = @(u,v) [2-v.*sin(u/2).*sin(u); 2-v.*sin(u/2).*cos(u); v.*cos(u/2)]; See the documenta...

17 hours ago | 0

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Answered

Issue solve function using complex numbers

I cannot figure out the reason solve is not solving for those values. I ended up with this: Rfcn = matlabFunction(Zeq) Rr(...

Issue solve function using complex numbers

I cannot figure out the reason solve is not solving for those values. I ended up with this: Rfcn = matlabFunction(Zeq) Rr(...

1 day ago | 0

Answered

Marking a single point on a graph

This first finds the approximate indices for the zero-crossings, then interpolates to find the exact values: sigma_x = 8; sig...

Marking a single point on a graph

This first finds the approximate indices for the zero-crossings, then interpolates to find the exact values: sigma_x = 8; sig...

1 day ago | 0

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Answered

A program for obtaining the tangent function algebraic formula in MATLAB

series taylor

A program for obtaining the tangent function algebraic formula in MATLAB

series taylor

2 days ago | 0

Answered

Interpolation when y data is not strictly a function of x

I am not certain what you want to do. Your data appear to be hysteresis curves. It is straightforward to fit them, using my ...

Interpolation when y data is not strictly a function of x

I am not certain what you want to do. Your data appear to be hysteresis curves. It is straightforward to fit them, using my ...

2 days ago | 0

| accepted

Answered

Plot a curve with coordinates

Without knowing what your data are, this will plot the peak and valley values as a functions of the indices: figure plot(inde...

Plot a curve with coordinates

Without knowing what your data are, this will plot the peak and valley values as a functions of the indices: figure plot(inde...

2 days ago | 0

Answered

How to represent a chaotic trajectory in MatLab?

I remember this system. I do not know what you intend by ‘chaotic trajectory’ here. If you want to plot the derivative of ‘k...

How to represent a chaotic trajectory in MatLab?

I remember this system. I do not know what you intend by ‘chaotic trajectory’ here. If you want to plot the derivative of ‘k...

2 days ago | 0

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Answered

finding prominent maxima and minima of a column vector

Although findpeaks needs some help here, it can find all four: [D,S] = xlsread('ab1.xlsx'); [pks,plocs] = findpeaks([D(:,2)...

finding prominent maxima and minima of a column vector

Although findpeaks needs some help here, it can find all four: [D,S] = xlsread('ab1.xlsx'); [pks,plocs] = findpeaks([D(:,2)...

3 days ago | 1

| accepted

Answered

Changing color of graphs in MATLAB plot

With 7000+ curves, it is unlikely that you are going to be able to distinguish them regardless of the colormap you use. I wou...

Changing color of graphs in MATLAB plot

With 7000+ curves, it is unlikely that you are going to be able to distinguish them regardless of the colormap you use. I wou...

3 days ago | 2

| accepted

Answered

How do you remove specific rows from a cell array?

One approach: C = {{'myPC\Documents\MATLAB\DataAnalysis\temp\6\Temp-20\TS1.csv' } {'myPC\Documents\MATLAB\DataAna...

How do you remove specific rows from a cell array?

One approach: C = {{'myPC\Documents\MATLAB\DataAnalysis\temp\6\Temp-20\TS1.csv' } {'myPC\Documents\MATLAB\DataAna...

3 days ago | 1

| accepted

Answered

How to represent the followind ODE system in MatLab?

Define ‘y’ as ‘x(1)’, ‘k’ as ‘x(2)’, and code it using those substitutions. (I coded it as a one-line anonymous function.) R...

How to represent the followind ODE system in MatLab?

Define ‘y’ as ‘x(1)’, ‘k’ as ‘x(2)’, and code it using those substitutions. (I coded it as a one-line anonymous function.) R...

3 days ago | 0

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Answered

plot quiver onto the base of a 3D plot

This seems to approximate what I believe you want: [x,y] = meshgrid(-80:80, -80:80); z = -(cosd(x).^2 + cosd(y).^2).^2; mesh...

plot quiver onto the base of a 3D plot

This seems to approximate what I believe you want: [x,y] = meshgrid(-80:80, -80:80); z = -(cosd(x).^2 + cosd(y).^2).^2; mesh...

3 days ago | 1

| accepted

Answered

How to add equation to function

Except for your ‘rocket’ function, most of that looks as though it should work. Leave out the subscript reference when you ar...

How to add equation to function

Except for your ‘rocket’ function, most of that looks as though it should work. Leave out the subscript reference when you ar...

4 days ago | 1

Answered

How to make a matrix from a for loop

If you need to do it with the loop, this works: t = 0:2:100; for k = 1:numel(t) h(k) = rocket(t(k)); if h>=0 ...

How to make a matrix from a for loop

If you need to do it with the loop, this works: t = 0:2:100; for k = 1:numel(t) h(k) = rocket(t(k)); if h>=0 ...

4 days ago | 0

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Answered

plotting root of Polynomial Equation

You need to extract the double arrays from the cells in ‘EQ’: plot(p,real([EQ2{:}]),'-', p,imag([EQ2{:}]),'--') The cell2mat...

plotting root of Polynomial Equation

You need to extract the double arrays from the cells in ‘EQ’: plot(p,real([EQ2{:}]),'-', p,imag([EQ2{:}]),'--') The cell2mat...

4 days ago | 0

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Answered

text scan question of amplitude and phase

Try this: c = {'-7.30313259052058e-002dB,-4.26354774426478e+000°'}; D = textscan(c{:}, '%fdB%f°', 'Delimiter',',') producing...

text scan question of amplitude and phase

Try this: c = {'-7.30313259052058e-002dB,-4.26354774426478e+000°'}; D = textscan(c{:}, '%fdB%f°', 'Delimiter',',') producing...

4 days ago | 0

Answered

How to Name Columns in a Table?

That looks like it should work. Try this: B = array2table(y) first, to be sure that all the columns in ‘y’ are actually be...

How to Name Columns in a Table?

That looks like it should work. Try this: B = array2table(y) first, to be sure that all the columns in ‘y’ are actually be...

4 days ago | 1

| accepted

Answered

How to isolate one pulse from a periodic pulse train

One approach: t = linspace(0, 2.3, 500); % Time Vector pulses = -0.1...

How to isolate one pulse from a periodic pulse train

One approach: t = linspace(0, 2.3, 500); % Time Vector pulses = -0.1...

4 days ago | 0

| accepted

Answered

Integration showing wrong answer

It is the correct result, although it may not be the one you were anticipaiting. Try this: syms x f(x) = sin(x)+2*cos(x) ...

Integration showing wrong answer

It is the correct result, although it may not be the one you were anticipaiting. Try this: syms x f(x) = sin(x)+2*cos(x) ...

4 days ago | 0

| accepted

Answered

How to determine the delay between two signals representing a single transition

There are several possibilities. One of course is the finddelay function and its friends. Others are findchangepts and ischa...

How to determine the delay between two signals representing a single transition

There are several possibilities. One of course is the finddelay function and its friends. Others are findchangepts and ischa...

4 days ago | 0

| accepted

Answered

transfer p value to z value

Use the norminv function. If you do not have the Statistics and Machine Learning Toolbox, y9ou can use this anonymous functio...

transfer p value to z value

Use the norminv function. If you do not have the Statistics and Machine Learning Toolbox, y9ou can use this anonymous functio...

4 days ago | 0

Answered

Can't load .mat file from subfolder

See: Can't load .mat file from subfolder

Can't load .mat file from subfolder

See: Can't load .mat file from subfolder

4 days ago | 0

Answered

Can't load .mat file from subfolder

All the subdirectories on your MATLAB user path must be included in the path definitions. See: What Is the MATLAB Search Path? ...

Can't load .mat file from subfolder

All the subdirectories on your MATLAB user path must be included in the path definitions. See: What Is the MATLAB Search Path? ...

4 days ago | 0

Answered

morse code encoder with sound

If you change the ‘morsecode2’ assignment and cast it to a char rather than string data type, it works: morsecode2 = morsecode...

morse code encoder with sound

If you change the ‘morsecode2’ assignment and cast it to a char rather than string data type, it works: morsecode2 = morsecode...

5 days ago | 0

| accepted

Answered

Calculate mean from plot of two vectores

In order to calculate the mean, the y-coordinate data would have to be interpolated to the same x-coordinate values, those spann...

Calculate mean from plot of two vectores

In order to calculate the mean, the y-coordinate data would have to be interpolated to the same x-coordinate values, those spann...

5 days ago | 0

Answered

Obtaining integral function from code

At that value, the subscript is no longer an integer. This is most likely a problem with floating-point calculation error. Usi...

Obtaining integral function from code

At that value, the subscript is no longer an integer. This is most likely a problem with floating-point calculation error. Usi...

5 days ago | 1

| accepted

Answered

long digit scaled fixed point?

I ma not certain what problem you are seeing. The format function may be what you want. For example: format long e n = ...

long digit scaled fixed point?

I ma not certain what problem you are seeing. The format function may be what you want. For example: format long e n = ...

5 days ago | 1

| accepted