11,442 total contributions since 2012

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Answered

How do I adjust my histogram to show approx. 50 different categorized bins with very small data?

You need to subscript ‘t’ to save it as a vector. Try this: iter=10000; FS=40; for n=1:iter Sy=2.11*10^8+(60*rand(1)...

How do I adjust my histogram to show approx. 50 different categorized bins with very small data?

You need to subscript ‘t’ to save it as a vector. Try this: iter=10000; FS=40; for n=1:iter Sy=2.11*10^8+(60*rand(1)...

8 hours ago | 0

| accepted

Answered

Using the 'Surf' command for variable 'x' values

It doesn’t work because ‘y’ is a vector. Try this: x= [1.158633 4.871195 7.667851 11.45038 22.11895 1.221922 3.77...

Using the 'Surf' command for variable 'x' values

It doesn’t work because ‘y’ is a vector. Try this: x= [1.158633 4.871195 7.667851 11.45038 22.11895 1.221922 3.77...

11 hours ago | 0

| accepted

Answered

Adding standard error bars to grouped bar graph

You are in luck in not using categorical variables, because this approach will not work with them (although I’ve not had the opp...

Adding standard error bars to grouped bar graph

You are in luck in not using categorical variables, because this approach will not work with them (although I’ve not had the opp...

14 hours ago | 0

Answered

Find next value above threshold

The find (link) command may be what you want. It will return the index of the value, so you can then use that index to get the ...

Find next value above threshold

The find (link) command may be what you want. It will return the index of the value, so you can then use that index to get the ...

15 hours ago | 0

Answered

Need to combine every other column of two row vectors of different sizes in MATLAB

One approach: A = [1 3 5 7 9 11 13 15 17]; B = [2 4 6 8 10 12]; C(1:2:numel(A)*2) = A; C(2:2:numel(B)*2) = B; C = C(1:mi...

Need to combine every other column of two row vectors of different sizes in MATLAB

One approach: A = [1 3 5 7 9 11 13 15 17]; B = [2 4 6 8 10 12]; C(1:2:numel(A)*2) = A; C(2:2:numel(B)*2) = B; C = C(1:mi...

17 hours ago | 1

| accepted

Answered

How do I multiply a column in a matrix by a range of values?

I am not at all certain what result you want. Try these: spark_rng = linspace(-12, 30, numel(sfd(:,3))); ...

How do I multiply a column in a matrix by a range of values?

I am not at all certain what result you want. Try these: spark_rng = linspace(-12, 30, numel(sfd(:,3))); ...

24 hours ago | 0

Answered

How to order variables by their size?

Try this: [~,ix] = sort(cellfun(@sum, onsets)); Out = names(ix) producing: Out = 1×3 cell array {["C"]} {["...

How to order variables by their size?

Try this: [~,ix] = sort(cellfun(@sum, onsets)); Out = names(ix) producing: Out = 1×3 cell array {["C"]} {["...

1 day ago | 1

| accepted

Answered

how to extract pcg signal features from a dataset for machine learning

See Wavelet Time Scattering Classification of Phonocardiogram Data (link).

how to extract pcg signal features from a dataset for machine learning

See Wavelet Time Scattering Classification of Phonocardiogram Data (link).

1 day ago | 0

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Answered

low pass filter to matrix

You can apply any filter to a matrix using the filtfilt (link) function to do the actual filtering. From the documentation: ...

low pass filter to matrix

You can apply any filter to a matrix using the filtfilt (link) function to do the actual filtering. From the documentation: ...

1 day ago | 0

Answered

How to locate last peak in data?

Use the findpeaks (link) function, most likely with the 'MinPeakHeight' name-value pair. Then use the second ‘locs’ output (an ...

How to locate last peak in data?

Use the findpeaks (link) function, most likely with the 'MinPeakHeight' name-value pair. Then use the second ‘locs’ output (an ...

1 day ago | 0

Answered

3D spectrum plot with massive data sets

The spectrogram (link) function will likely do what you want.

3D spectrum plot with massive data sets

The spectrogram (link) function will likely do what you want.

1 day ago | 0

Answered

Sample a continuous signal with Sampling frequency

‘Would I do this by only looking at the points of the signal that correspond to the sampling frequency I decide on?’ Yes. In...

Sample a continuous signal with Sampling frequency

‘Would I do this by only looking at the points of the signal that correspond to the sampling frequency I decide on?’ Yes. In...

2 days ago | 0

Answered

Syntax Question struct array - Unexpected MATLAB operator.

Refer to general arguments in your function definition, not specific variables. So your function would be defined as: funct...

Syntax Question struct array - Unexpected MATLAB operator.

Refer to general arguments in your function definition, not specific variables. So your function would be defined as: funct...

2 days ago | 0

| accepted

Answered

changing diagional values with different values

I am not certain what result you want. Try this: MX1 = randi(9, 4) D1 = diag(MX1); Xv = sum(MX1,2) - D1; MX1 = triu(MX1,...

changing diagional values with different values

I am not certain what result you want. Try this: MX1 = randi(9, 4) D1 = diag(MX1); Xv = sum(MX1,2) - D1; MX1 = triu(MX1,...

2 days ago | 1

| accepted

Answered

Inserting Timestamp into a Matrix

I still have no idea what you want to do. However, if you want to concatenate the even rows to the odd rows and have ‘2019’ b...

Inserting Timestamp into a Matrix

I still have no idea what you want to do. However, if you want to concatenate the even rows to the odd rows and have ‘2019’ b...

2 days ago | 0

Answered

Taking second derivative and solving it for when it equals 0

I am not certain what you are doing. Taking the derivative of data will significantly amplify any noise that might be present, ...

Taking second derivative and solving it for when it equals 0

I am not certain what you are doing. Taking the derivative of data will significantly amplify any noise that might be present, ...

2 days ago | 0

| accepted

Answered

reassigning a value in a piecewise function

I am not exactly certain what you want to do. Try this: syms y(x) y(x) = piecewise(0<=x<25, 0,25<=x<=50, 0.5+x/50, 50<=x<=...

reassigning a value in a piecewise function

I am not exactly certain what you want to do. Try this: syms y(x) y(x) = piecewise(0<=x<25, 0,25<=x<=50, 0.5+x/50, 50<=x<=...

2 days ago | 0

Answered

How can i store values calculated in my loop

I am not certain what you are doing. One option is to create a second matrix (‘X2’ here), and store the results in it: X = [9...

How can i store values calculated in my loop

I am not certain what you are doing. One option is to create a second matrix (‘X2’ here), and store the results in it: X = [9...

3 days ago | 1

| accepted

Answered

How do i know the limits for maxfunevals and tolx?

You can set them to be whatever you like (within limits). If you want to know the default values, use an optimoptions (link) ca...

How do i know the limits for maxfunevals and tolx?

You can set them to be whatever you like (within limits). If you want to know the default values, use an optimoptions (link) ca...

3 days ago | 1

Answered

Finding closest point to known coordinates

The minimum distance of a set of points is the Centroid (link), defined as the mean of the coordinates of the points: xy = [1 ...

Finding closest point to known coordinates

The minimum distance of a set of points is the Centroid (link), defined as the mean of the coordinates of the points: xy = [1 ...

3 days ago | 0

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Answered

How to sum data points within contour lines/isolines?

You can certainly get the (x,y) coordinates of the contours, although it takes a bit of code the get the result you likely want....

How to sum data points within contour lines/isolines?

You can certainly get the (x,y) coordinates of the contours, although it takes a bit of code the get the result you likely want....

3 days ago | 0

Answered

Scattering 3D points (x y z) on a 2D plot (x y)

Use the scatter3 (link) function, and the view (link) function, specifically: view(0, 90)

Scattering 3D points (x y z) on a 2D plot (x y)

Use the scatter3 (link) function, and the view (link) function, specifically: view(0, 90)

3 days ago | 0

| accepted

Answered

Creating function for baseline correction

If you want to understand how to write MATLAB functions, see: Function Basics (link).

Creating function for baseline correction

If you want to understand how to write MATLAB functions, see: Function Basics (link).

3 days ago | 1

| accepted

Answered

anyway to compare date in Matlab

It might be easier to use the datenum field instead if you simply want to compare dates: filenames1=dir'(D:/test/); time_file...

anyway to compare date in Matlab

It might be easier to use the datenum field instead if you simply want to compare dates: filenames1=dir'(D:/test/); time_file...

3 days ago | 0

Answered

plotting an N segments circle

WHY? Because you are plotting a decagon rather than a circle. If you want them to be on the line, you need to reduce their rad...

plotting an N segments circle

WHY? Because you are plotting a decagon rather than a circle. If you want them to be on the line, you need to reduce their rad...

3 days ago | 1

| accepted

Answered

Inputting a certain number of data points between two values

x = linspace(0, pi, 10);

Inputting a certain number of data points between two values

x = linspace(0, pi, 10);

3 days ago | 0

| accepted

Answered

Error using < Matrix dimensions must agree.

You apparently have R2016a or earlier, so you do not have ‘automatic implicit expansion’ that was part of R2016b and later versi...

Error using < Matrix dimensions must agree.

You apparently have R2016a or earlier, so you do not have ‘automatic implicit expansion’ that was part of R2016b and later versi...

4 days ago | 0

| accepted

Answered

How do I name the trendline in the legend? Also, how can I get the trend line equation on the plot?

It is not possible to run an image of your code. Try this: Voltage = linspace(10.45, -1.4, 8); GaugePressure = linspace(33...

How do I name the trendline in the legend? Also, how can I get the trend line equation on the plot?

It is not possible to run an image of your code. Try this: Voltage = linspace(10.45, -1.4, 8); GaugePressure = linspace(33...

4 days ago | 0

Answered

Resampling a matrix of data to increase data sample rate

Use the Signal Processing Toolbox resample (link) function. It is specifically designed for signal resampling, and includes an ...

Resampling a matrix of data to increase data sample rate

Use the Signal Processing Toolbox resample (link) function. It is specifically designed for signal resampling, and includes an ...

4 days ago | 0

| accepted