12,782 total contributions since 2012

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PROFESSIONAL: Physician (M.D.): Diplomate of the American Board of Internal Medicine; M.Sc. Biomedical Engineering: Instrumentation, Signal Processing, Control, System Identification, Parameter Estimation

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Answered

ERROR : "Input arguments must be convertible to floating-point numbers"

The min function is not compatible with symbolic objects, for obvious reasons. Try this instead: b=300; %mm d=400; %mm ...

ERROR : "Input arguments must be convertible to floating-point numbers"

The min function is not compatible with symbolic objects, for obvious reasons. Try this instead: b=300; %mm d=400; %mm ...

2 hours ago | 0

Answered

how to create magnitude spectrum signal based on data from excel

Your code needs a few slight improvements: dataset=xlsread('Group3.xlsx','Sheet1','A1:ALM1'); stepsize=0.001; N=1; t=0:step...

how to create magnitude spectrum signal based on data from excel

Your code needs a few slight improvements: dataset=xlsread('Group3.xlsx','Sheet1','A1:ALM1'); stepsize=0.001; N=1; t=0:step...

4 hours ago | 0

Answered

How can I solve a system of differential equations where one equation contains the answer to another?

If you have the Symbolic Math Toolbox, let it do the ‘heavy lifting’: syms omegax(t) omegay(t) omegas Omega(t) epsilon sigma a...

How can I solve a system of differential equations where one equation contains the answer to another?

If you have the Symbolic Math Toolbox, let it do the ‘heavy lifting’: syms omegax(t) omegay(t) omegas Omega(t) epsilon sigma a...

8 hours ago | 0

| accepted

Answered

cannot get fftshift to shift frequency

You need to create the frequency vector yourself. Probably the easiest way is to use the linspace function. Try this: VAC...

cannot get fftshift to shift frequency

You need to create the frequency vector yourself. Probably the easiest way is to use the linspace function. Try this: VAC...

9 hours ago | 0

Answered

Example ('predmaint/RollingElementBearingFaultDiagnosisExample')

From the documentation on Rolling Element Bearing Fault Diagnosis: ‘For the full dataset, go to this link https://githu...

Example ('predmaint/RollingElementBearingFaultDiagnosisExample')

From the documentation on Rolling Element Bearing Fault Diagnosis: ‘For the full dataset, go to this link https://githu...

9 hours ago | 0

Answered

Passing a vector through a built in function?

Do element-wise multiplication and division: V=sqrt((2*W.*cosd(theta))./(CL*p6000)); ↑ ↑ S...

Passing a vector through a built in function?

Do element-wise multiplication and division: V=sqrt((2*W.*cosd(theta))./(CL*p6000)); ↑ ↑ S...

24 hours ago | 0

| accepted

Answered

How do I get the date out of a filename using regexp?

There are likely several ways to approach this. I would do it a bit differently: str = 'xxx_2014_06_03_00_00_01'; fdate = re...

How do I get the date out of a filename using regexp?

There are likely several ways to approach this. I would do it a bit differently: str = 'xxx_2014_06_03_00_00_01'; fdate = re...

1 day ago | 0

| accepted

Answered

Name the first column in array2table

The code you posted produces an acceptable table object. I am not certain what you want. I am guessing here: coeff = rand(...

Name the first column in array2table

The code you posted produces an acceptable table object. I am not certain what you want. I am guessing here: coeff = rand(...

1 day ago | 0

| accepted

Answered

I'm trying to define a simbolic variable like ¨ syms x ¨. I used to do it but now It doesn't work..

Run these lines from your Command Window or a script: restoredefaultpath rehash toolboxcache If doing that does not solve ...

I'm trying to define a simbolic variable like ¨ syms x ¨. I used to do it but now It doesn't work..

Run these lines from your Command Window or a script: restoredefaultpath rehash toolboxcache If doing that does not solve ...

1 day ago | 0

Answered

Reduce data points from 200 to 108

I have no idea what your data are or what you want to do with them, other than reduce the number of them. Interpolating them ...

Reduce data points from 200 to 108

I have no idea what your data are or what you want to do with them, other than reduce the number of them. Interpolating them ...

1 day ago | 0

| accepted

Answered

How to make 3D-line plots (Sine Wave)?

With three small changes to your code, it works: t = 0:0.01:5*pi; z = 0:pi/12:2*pi; phase = 0; ...

How to make 3D-line plots (Sine Wave)?

With three small changes to your code, it works: t = 0:0.01:5*pi; z = 0:pi/12:2*pi; phase = 0; ...

1 day ago | 0

| accepted

Answered

'Character vector is not terminated properly' when I am trying to open a .fis file in MATLAB

You likely either forgot a closing single quotation mark (') or you inserted one in error. Without seeing your code, it is no...

'Character vector is not terminated properly' when I am trying to open a .fis file in MATLAB

You likely either forgot a closing single quotation mark (') or you inserted one in error. Without seeing your code, it is no...

1 day ago | 0

| accepted

Answered

Identifying x value at y on an xy plot

A common problem interpolating y-values that are not unique is how to make them appropriate for interpolation. One way is to si...

Identifying x value at y on an xy plot

A common problem interpolating y-values that are not unique is how to make them appropriate for interpolation. One way is to si...

1 day ago | 0

| accepted

Answered

Plots appear as giant blocks rather than actual waveforms

The waveforms are there. The problem is that they are very densely packed in those images, so they appear as blue blocks. Us...

Plots appear as giant blocks rather than actual waveforms

The waveforms are there. The problem is that they are very densely packed in those images, so they appear as blue blocks. Us...

2 days ago | 0

| accepted

Answered

Area between curve (numerical data with positive and negative values) and y = 0

I do not have a clear idea of what you want as the result. It is relatively straightforward to integrate the areas greater th...

Area between curve (numerical data with positive and negative values) and y = 0

I do not have a clear idea of what you want as the result. It is relatively straightforward to integrate the areas greater th...

2 days ago | 0

| accepted

Answered

Average of Wave from 10 waves in single graph

Try this: D = load('P_191005_000.mat'); ap = D.b; Ts = 1E-3; ...

Average of Wave from 10 waves in single graph

Try this: D = load('P_191005_000.mat'); ap = D.b; Ts = 1E-3; ...

2 days ago | 2

| accepted

Answered

How to take Average of many waves to single wave(want he averge of all waves to a single wave)

Used the islocalmin function to find the minima of the waveform, then use those indices to store the wave segments in a cell arr...

How to take Average of many waves to single wave(want he averge of all waves to a single wave)

Used the islocalmin function to find the minima of the waveform, then use those indices to store the wave segments in a cell arr...

2 days ago | 1

| accepted

Answered

give labels according to string

Try this: String = {'Abc\a1\L\XYZ1R08' 'Abc\a1\R\XYZ1R09' 'Abc\a1\R\XYZ1R10' 'Abc\b2\L\XYZ2L01' 'Abc\b2\R\XYZ2L02' 'A...

give labels according to string

Try this: String = {'Abc\a1\L\XYZ1R08' 'Abc\a1\R\XYZ1R09' 'Abc\a1\R\XYZ1R10' 'Abc\b2\L\XYZ2L01' 'Abc\b2\R\XYZ2L02' 'A...

2 days ago | 1

| accepted

Answered

Help, How to convert image to binary image ?

See if im2bw (R2015b and earlier) or imbinarize (R2016a and alter) will do what you want.

Help, How to convert image to binary image ?

See if im2bw (R2015b and earlier) or imbinarize (R2016a and alter) will do what you want.

2 days ago | 0

| accepted

Answered

find transfer function of input and output signals and then perform an FFT.

This should get you started: [D,S] = xlsread('Test_data_1.xlsx'); torg = D(:,1); ...

find transfer function of input and output signals and then perform an FFT.

This should get you started: [D,S] = xlsread('Test_data_1.xlsx'); torg = D(:,1); ...

2 days ago | 1

| accepted

Answered

Extract and code gender string as number using if loop

I do not udnerstand the reason strcmp or strncmp would not work with your structure data. We may have to see ‘tempfile.data.gen...

Extract and code gender string as number using if loop

I do not udnerstand the reason strcmp or strncmp would not work with your structure data. We may have to see ‘tempfile.data.gen...

2 days ago | 0

| accepted

Answered

Interpolation of scattered earthquake data

There are several options. First, see if the griddata function will do what you want. (The Mapping Toolbox may have more appli...

Interpolation of scattered earthquake data

There are several options. First, see if the griddata function will do what you want. (The Mapping Toolbox may have more appli...

3 days ago | 0

| accepted

Answered

SUM OF (-1^K)/FACTORIAL(K+1)

First, use element-wise operations: k = 1:6; v = (-1).^k./factorial(k+1) sv = sum(v) See Array vs. Matrix Operations for a ...

SUM OF (-1^K)/FACTORIAL(K+1)

First, use element-wise operations: k = 1:6; v = (-1).^k./factorial(k+1) sv = sum(v) See Array vs. Matrix Operations for a ...

3 days ago | 0

Answered

The magnitude in Bode plot differs from the mag values returned with: [mag,phase,wout] = bode(G,win)

The output magnitudes are not in decibels. If you instead use: mag_dB = 20*log10(mag) the result is: mag_dB = 27.7802...

The magnitude in Bode plot differs from the mag values returned with: [mag,phase,wout] = bode(G,win)

The output magnitudes are not in decibels. If you instead use: mag_dB = 20*log10(mag) the result is: mag_dB = 27.7802...

3 days ago | 0

| accepted

Answered

Format colorbar using engineering notation

Try this: engstr = @(x) [x(:).*10.^(-3*floor(log10(abs(x(:)))/3)) 3*floor(log10(abs(x(:)))/3)]; Q1 = logspace(-3, 3, 7); ...

Format colorbar using engineering notation

Try this: engstr = @(x) [x(:).*10.^(-3*floor(log10(abs(x(:)))/3)) 3*floor(log10(abs(x(:)))/3)]; Q1 = logspace(-3, 3, 7); ...

3 days ago | 0

| accepted

Answered

Failure in initial objective function evaluation. FMINUNC cannot continue.

Unless it is already in a function file, it needs to be an anonymous function: f = @(x) x(2)^2*x(9)^2 + x(2)^2*x(9) + x(2)^3*x...

Failure in initial objective function evaluation. FMINUNC cannot continue.

Unless it is already in a function file, it needs to be an anonymous function: f = @(x) x(2)^2*x(9)^2 + x(2)^2*x(9) + x(2)^3*x...

3 days ago | 1

| accepted

Answered

Read several large csv and store as separate variables

Perhaps saving it in a cell array would work: file{i}=readmatrix(filename); Note the curly brackets {} denoting cell-array i...

Read several large csv and store as separate variables

Perhaps saving it in a cell array would work: file{i}=readmatrix(filename); Note the curly brackets {} denoting cell-array i...

4 days ago | 0

Answered

How to quickly find the maximum group of same rows in a matrix?

Try this: A = [0 1 0 1 0 0 0 0; 1 0 0 0 1 0 0 0; 1 0 0 0 ...

How to quickly find the maximum group of same rows in a matrix?

Try this: A = [0 1 0 1 0 0 0 0; 1 0 0 0 1 0 0 0; 1 0 0 0 ...

4 days ago | 0

| accepted

Answered

Display Markers At Specific Data Points

The MarkerIndices name-value pair is relatively new. If you do not have it, it is straightforward to do that with a second plo...

Display Markers At Specific Data Points

The MarkerIndices name-value pair is relatively new. If you do not have it, it is straightforward to do that with a second plo...

4 days ago | 1

| accepted

Answered

Units for Magnitude after Fast Fourier Transform (FFT) is done

The magnitude units are the same as the time-domain amplitude units, unless you transform them in some way (such as squaring to ...

Units for Magnitude after Fast Fourier Transform (FFT) is done

The magnitude units are the same as the time-domain amplitude units, unless you transform them in some way (such as squaring to ...

4 days ago | 0