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Answered

anonymous function and plotting

You are essentially where you want to be. It helps to assign the output of your function to a different variable. (I use ‘v’ h...

anonymous function and plotting

You are essentially where you want to be. It helps to assign the output of your function to a different variable. (I use ‘v’ h...

2 hours ago | 0

| accepted

Answered

How to change ASCII values?

You are not using tthe result of the upper call. See if: u = upper(k) y = double(u) is more appropriate.

How to change ASCII values?

You are not using tthe result of the upper call. See if: u = upper(k) y = double(u) is more appropriate.

1 day ago | 0

Answered

How to vary a value inside an integral which is not getting integrated itself?

The integral2 and integral3 functions do not allow the 'ArrayValued' name-value pair, so it is necessary to ‘nest’ integral call...

How to vary a value inside an integral which is not getting integrated itself?

The integral2 and integral3 functions do not allow the 'ArrayValued' name-value pair, so it is necessary to ‘nest’ integral call...

1 day ago | 0

Answered

how to get best 10 fitness values

If you have R2017b or later, mink would be easiest. Otherwise, use sort and take the first 10. (This assumes that ‘fitness’ is...

how to get best 10 fitness values

If you have R2017b or later, mink would be easiest. Otherwise, use sort and take the first 10. (This assumes that ‘fitness’ is...

1 day ago | 0

Answered

stem fuction shows error everytime

You have a script file that you named ‘stem’. This is called ‘overhsadowing’ a MATLAB function. The solution is to find the ...

stem fuction shows error everytime

You have a script file that you named ‘stem’. This is called ‘overhsadowing’ a MATLAB function. The solution is to find the ...

1 day ago | 0

Answered

Plotting two functions on 3D surface for the same interval

Try this: x = 0:10; Z1=x.^2; Z2=x.^3; figure surf(Z1.'*Z2) Another possibility: figure surf([Z1; Z2]) It is not cer...

Plotting two functions on 3D surface for the same interval

Try this: x = 0:10; Z1=x.^2; Z2=x.^3; figure surf(Z1.'*Z2) Another possibility: figure surf([Z1; Z2]) It is not cer...

2 days ago | 0

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Answered

Extract values common to 5 columns

Since it is not homework, see if this does what you want: A = randi(9,20,5); % Create Mat...

Extract values common to 5 columns

Since it is not homework, see if this does what you want: A = randi(9,20,5); % Create Mat...

2 days ago | 0

Answered

How to use a vector to index another vector?

Testing the code (without the function definition or function call): t = (0:0.1:15); in = sin(t*2*pi); w = 5; out = in*0;...

How to use a vector to index another vector?

Testing the code (without the function definition or function call): t = (0:0.1:15); in = sin(t*2*pi); w = 5; out = in*0;...

2 days ago | 0

Answered

how can i work with two variables with genetic algorithm

It would be helpful to know what your fitness function is doing. If there are independent variables, you can combine them as:...

how can i work with two variables with genetic algorithm

It would be helpful to know what your fitness function is doing. If there are independent variables, you can combine them as:...

2 days ago | 0

Answered

I want to generate a time vector

start = datetime('6:30 AM', 'InputFormat','h:mm a'); finish = datetime('3:00 PM', 'InputFormat','h:mm a'); interval = minutes(...

I want to generate a time vector

start = datetime('6:30 AM', 'InputFormat','h:mm a'); finish = datetime('3:00 PM', 'InputFormat','h:mm a'); interval = minutes(...

2 days ago | 0

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Answered

Is there a way to set the xticklabel text alignment

The example in Specify x-Axis Tick Values and Labels appear to be centre-aligned.

Is there a way to set the xticklabel text alignment

The example in Specify x-Axis Tick Values and Labels appear to be centre-aligned.

3 days ago | 0

Answered

If elseif else statement inside a loop

Perhaps: for k = 1:5 YourGrade= input('Enter your number grade:') if YourGrade >= 90; disp('Your grade is a...

If elseif else statement inside a loop

Perhaps: for k = 1:5 YourGrade= input('Enter your number grade:') if YourGrade >= 90; disp('Your grade is a...

3 days ago | 0

Answered

NaN issue when calculating for a mean value

The NaN result is due to one or more elements of the vector you are taking the mean of being (0/0) or (Inf/Inf), since they eval...

NaN issue when calculating for a mean value

The NaN result is due to one or more elements of the vector you are taking the mean of being (0/0) or (Inf/Inf), since they eval...

3 days ago | 0

Answered

Least squares regression of a quadratic without bx term.

Try this: DM = [x(:).^2 ones(size(x(:)))]; % Design Matrix B = DM \ y(:); ...

Least squares regression of a quadratic without bx term.

Try this: DM = [x(:).^2 ones(size(x(:)))]; % Design Matrix B = DM \ y(:); ...

3 days ago | 0

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Answered

FFT analysis of multiple signals with the same response length

The fft function operates column-wise (unless the argument is a vector or you tell it otherwise), so this is all that is necessa...

FFT analysis of multiple signals with the same response length

The fft function operates column-wise (unless the argument is a vector or you tell it otherwise), so this is all that is necessa...

3 days ago | 0

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Answered

solving differential equation and assigning value to symfun

Try this: t_val = vpasolve(ySol==1,t) % Symbolic Solution

solving differential equation and assigning value to symfun

Try this: t_val = vpasolve(ySol==1,t) % Symbolic Solution

3 days ago | 0

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Answered

Solving for a variable in equation

Use a root-finding function (I chose fzero here), then take the known variable values, create an anonymous function from the exp...

Solving for a variable in equation

Use a root-finding function (I chose fzero here), then take the known variable values, create an anonymous function from the exp...

4 days ago | 0

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Answered

How to find data values that falls on line connecting loglog plot in matlab

To get a smooth interpolation, it is necessary to do two transformations on it. First, interpolate log(y), and then take the ex...

How to find data values that falls on line connecting loglog plot in matlab

To get a smooth interpolation, it is necessary to do two transformations on it. First, interpolate log(y), and then take the ex...

4 days ago | 0

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Answered

Magnitude, row and column in a Matrix

Try this: A = [87.97 87.97 17.97 95.22 87.96 91.26 75.50 75.50 75.50 78.13 64.89 78.90]; ...

Magnitude, row and column in a Matrix

Try this: A = [87.97 87.97 17.97 95.22 87.96 91.26 75.50 75.50 75.50 78.13 64.89 78.90]; ...

4 days ago | 0

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Answered

How to solve non linear system of ODE

If you are fitting the differential equations to data, see Monod kinetics and curve fitting and Parameter Estimation for a Syste...

How to solve non linear system of ODE

If you are fitting the differential equations to data, see Monod kinetics and curve fitting and Parameter Estimation for a Syste...

4 days ago | 0

Answered

How do I obtain the derivatives after interp2 with the 'spline' option?

To get a numerical derivative, use the gradient function. With a matrix input, request two outputs. See Contour Plot of Vect...

How do I obtain the derivatives after interp2 with the 'spline' option?

To get a numerical derivative, use the gradient function. With a matrix input, request two outputs. See Contour Plot of Vect...

4 days ago | 0

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Answered

How to plot a two variable function?

Apparently ‘x’ is a vector. That means that ‘z’ produces only two values. You could plot it as: figure plot(z, 'p') howe...

How to plot a two variable function?

Apparently ‘x’ is a vector. That means that ‘z’ produces only two values. You could plot it as: figure plot(z, 'p') howe...

4 days ago | 0

Answered

Easiest way to skip a few lines and then read data from this text file ( x and y) to draw a plot.

The easiest way I can think of is to use the dlmread function: filename = '6in_nomass_5.txt'; Data = dlmread(filename, '\t', ...

Easiest way to skip a few lines and then read data from this text file ( x and y) to draw a plot.

The easiest way I can think of is to use the dlmread function: filename = '6in_nomass_5.txt'; Data = dlmread(filename, '\t', ...

4 days ago | 0

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Answered

X,Y data of irregular grid, scatter plot with Z data

It is not obvious to me what you want. You already appear to have tried reshape, although I have no idea what the arguments ...

X,Y data of irregular grid, scatter plot with Z data

It is not obvious to me what you want. You already appear to have tried reshape, although I have no idea what the arguments ...

4 days ago | 0

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Answered

How do I synchronize stress-strain data?

If you want both of them to have the same sampling frequency, use the resample function on one of them. That will make the proc...

How do I synchronize stress-strain data?

If you want both of them to have the same sampling frequency, use the resample function on one of them. That will make the proc...

4 days ago | 0

Answered

How to find the best parameters to fit damped oscillations curves

See: How to filter noise from time-frequency data and find natural frequency of a cantilever? Specifically: D = load('Lo...

How to find the best parameters to fit damped oscillations curves

See: How to filter noise from time-frequency data and find natural frequency of a cantilever? Specifically: D = load('Lo...

4 days ago | 1

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Answered

fminsearch for fitting a function to experimental data

There are several errors in the posted code, as Walter noted, mostly involving implicit multiplication, that MATLAB does not rec...

fminsearch for fitting a function to experimental data

There are several errors in the posted code, as Walter noted, mostly involving implicit multiplication, that MATLAB does not rec...

4 days ago | 0

Answered

Interpolate Data and find the matching x-Value

Try this: data=[1 2, 2 3, 3 3, 4 5, 7 9]; xval = @(yval) fsolve(@(x) interp1(data(:,1...

Interpolate Data and find the matching x-Value

Try this: data=[1 2, 2 3, 3 3, 4 5, 7 9]; xval = @(yval) fsolve(@(x) interp1(data(:,1...

4 days ago | 0

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Answered

Why ('t=(2x+1)/(2x-2)','x') is unsolvable?

Correct syntax: syms t x solve(t==(2*x+1)/(2*x-2),x) producing: ans = (2*t + 1)/(2*t - 2)

Why ('t=(2x+1)/(2x-2)','x') is unsolvable?

Correct syntax: syms t x solve(t==(2*x+1)/(2*x-2),x) producing: ans = (2*t + 1)/(2*t - 2)

5 days ago | 0

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Answered

Wrong FFT for an audio file

The plot is correct. You are not considering the exponential multiplication at the right end of the frequency axis. This mak...

Wrong FFT for an audio file

The plot is correct. You are not considering the exponential multiplication at the right end of the frequency axis. This mak...

5 days ago | 0

| accepted