I'm an electrical engineer by education.

Professional Interests: signal processing, image processing, linear algebra.

Answered

Nufftn yields only zeros for nonuniform grid. Bug?

Yes, this appears to be a bug. Please open a case with technical support.

Nufftn yields only zeros for nonuniform grid. Bug?

Yes, this appears to be a bug. Please open a case with technical support.

3 months ago | 0

| accepted

Answered

when smoothing data with gaussian how to define sd and mean

The 'gaussian' method for smoothdata uses a fixed (but window-dependent) standard deviation, and mean of zero. If you want to s...

when smoothing data with gaussian how to define sd and mean

The 'gaussian' method for smoothdata uses a fixed (but window-dependent) standard deviation, and mean of zero. If you want to s...

1 year ago | 1

| accepted

Answered

Moving Average of Matrix over 10 min interval

The error message could be clearer about the problem you're having, but you're getting the message because you've misspelled "Sa...

Moving Average of Matrix over 10 min interval

The error message could be clearer about the problem you're having, but you're getting the message because you've misspelled "Sa...

1 year ago | 0

Answered

find local maxima around a point

If you can provide a MAT file with the data, it would be helpful in answering the question more concretely. You should be able ...

find local maxima around a point

If you can provide a MAT file with the data, it would be helpful in answering the question more concretely. You should be able ...

1 year ago | 0

Answered

Cut a signal into heart cycle pieces

I don't have your data, but using something that looks roughly similar (attached), here's an approach. Furthering John's commen...

Cut a signal into heart cycle pieces

I don't have your data, but using something that looks roughly similar (attached), here's an approach. Furthering John's commen...

1 year ago | 1

| accepted

Answered

How do I identify subsets of data and divide the data into the subsets

Mark's answer is a great way of doing this. In addition, you might consider looking at the ischange function: % Look for at mo...

How do I identify subsets of data and divide the data into the subsets

Mark's answer is a great way of doing this. In addition, you might consider looking at the ischange function: % Look for at mo...

1 year ago | 0

Answered

How does "smoothdata" function using "gaussian" method define the standard deviation for different window size?

The standard deviation of the Gaussian for |smoothdata| is fixed to be 1/5th of the total window width, so there is a direct lin...

How does "smoothdata" function using "gaussian" method define the standard deviation for different window size?

The standard deviation of the Gaussian for |smoothdata| is fixed to be 1/5th of the total window width, so there is a direct lin...

2 years ago | 1

| accepted

Answered

How to make a softer plot using a moving average every ''x'' skips?

It sounds like what you might want to do is put your data into a <https://www.mathworks.com/help/matlab/ref/timetable.html |time...

How to make a softer plot using a moving average every ''x'' skips?

It sounds like what you might want to do is put your data into a <https://www.mathworks.com/help/matlab/ref/timetable.html |time...

2 years ago | 0

Answered

Using smoothdata on tallaray that contains time

|smoothdata| does not support tall timetables, and similarly does not support the |'SamplePoints'| Name-Value pair for tall inpu...

Using smoothdata on tallaray that contains time

|smoothdata| does not support tall timetables, and similarly does not support the |'SamplePoints'| Name-Value pair for tall inpu...

2 years ago | 0

Answered

how to find and mark the value of local minimums in a graph of multiple data ?

If you have access to R2017b, you might also consider checking out the <https://www.mathworks.com/help/matlab/ref/islocalmin.htm...

how to find and mark the value of local minimums in a graph of multiple data ?

If you have access to R2017b, you might also consider checking out the <https://www.mathworks.com/help/matlab/ref/islocalmin.htm...

2 years ago | 0

Answered

Find sudden jumps in signal

If you have access to R2017b, try taking a look at the <https://www.mathworks.com/help/matlab/ref/ischange.html |ischange| funct...

Find sudden jumps in signal

If you have access to R2017b, try taking a look at the <https://www.mathworks.com/help/matlab/ref/ischange.html |ischange| funct...

2 years ago | 0

Answered

Data segmentation for Accelerometer time series data

For the segmentation, if you have R2017b, <https://www.mathworks.com/help/matlab/ref/ischange.html the new |ischange| function> ...

Data segmentation for Accelerometer time series data

For the segmentation, if you have R2017b, <https://www.mathworks.com/help/matlab/ref/ischange.html the new |ischange| function> ...

2 years ago | 0

Answered

How to write a circulant matrix , where the elements are matrices? Thanks!

Supposing the matrices you want to use in a circulant pattern are stored as a |M| x |N| x |K| array (where |M| x |N| is the size...

How to write a circulant matrix , where the elements are matrices? Thanks!

Supposing the matrices you want to use in a circulant pattern are stored as a |M| x |N| x |K| array (where |M| x |N| is the size...

3 years ago | 0

Answered

Sorting the complex array elements with imaginary part along with it.

If you have a recent version of MATLAB, try checking out the <https://www.mathworks.com/help/matlab/ref/sort.html#namevaluepaira...

Sorting the complex array elements with imaginary part along with it.

If you have a recent version of MATLAB, try checking out the <https://www.mathworks.com/help/matlab/ref/sort.html#namevaluepaira...

3 years ago | 2

Answered

Efficient moving average of scattered data

If you can upgrade to R2017a, this functionality can now be achieved through the 'SamplePoints' name-value pair in the moving st...

Efficient moving average of scattered data

If you can upgrade to R2017a, this functionality can now be achieved through the 'SamplePoints' name-value pair in the moving st...

3 years ago | 1

Answered

Delete rows with NaN records

Not that this question needed another answer, but, you can also check out the <http://www.mathworks.com/help/matlab/ref/rmmissin...

Delete rows with NaN records

Not that this question needed another answer, but, you can also check out the <http://www.mathworks.com/help/matlab/ref/rmmissin...

3 years ago | 2

Answered

How to replace a NaN element with an preceeding element in a matrix using logical indexing?

As far as replacing with the previous non-NaN element, you could check out the <http://www.mathworks.com/help/matlab/ref/fillmis...

How to replace a NaN element with an preceeding element in a matrix using logical indexing?

As far as replacing with the previous non-NaN element, you could check out the <http://www.mathworks.com/help/matlab/ref/fillmis...

3 years ago | 0

Answered

How to use "movsum()" with panel data in a table using loop mechanisms?

I think you just want to use |sum| here, and not |movsum|, since you're summing over different columns each time. Regardless, t...

How to use "movsum()" with panel data in a table using loop mechanisms?

I think you just want to use |sum| here, and not |movsum|, since you're summing over different columns each time. Regardless, t...

3 years ago | 1

| accepted

Answered

How to calculate Sums in a Panel Data framework using "For Loops"

To get the moving sum of the previous 12 elements, and marking all windows NaN where you don't have 11 previous points, you can ...

How to calculate Sums in a Panel Data framework using "For Loops"

To get the moving sum of the previous 12 elements, and marking all windows NaN where you don't have 11 previous points, you can ...

3 years ago | 0

| accepted

Answered

Convolution of many vectors

You can use a fun trick here. Each of these polynomials is a quadratic, so you can find their roots easily enough: F = F(:...

Convolution of many vectors

You can use a fun trick here. Each of these polynomials is a quadratic, so you can find their roots easily enough: F = F(:...

3 years ago | 0

Answered

How to exclude the center/current number when performing movmax?

There's no direct way to exclude the current point in a given window with the moving statistics functions. However, since you w...

How to exclude the center/current number when performing movmax?

There's no direct way to exclude the current point in a given window with the moving statistics functions. However, since you w...

3 years ago | 1

| accepted

Answered

Help on calculating cumulative moving average

If you're trying to do a cumulative moving mean, where each time you move to the next element it is the mean of that element and...

Help on calculating cumulative moving average

If you're trying to do a cumulative moving mean, where each time you move to the next element it is the mean of that element and...

4 years ago | 2

Answered

mean value of a group of data with NaNs

You can also just use the 'omitnan' option in "mean": A = [1 0 0 1 NaN 1 NaN 0]; M = mean(A,'omitnan') M = 0.5...

mean value of a group of data with NaNs

You can also just use the 'omitnan' option in "mean": A = [1 0 0 1 NaN 1 NaN 0]; M = mean(A,'omitnan') M = 0.5...

4 years ago | 2

Answered

How to convert the mean value of an integer matrix to a double

Are regionA and regionB allocated as integers? It seems likely he final assignment that is casting them back to integers. Sinc...

How to convert the mean value of an integer matrix to a double

Are regionA and regionB allocated as integers? It seems likely he final assignment that is casting them back to integers. Sinc...

4 years ago | 0

| accepted

Answered

How to limit rounding in matrix division

Your last sentence has the answer: your data type is uint8. Dividing a uint8 by a uint8 is going to give you another integer, s...

How to limit rounding in matrix division

Your last sentence has the answer: your data type is uint8. Dividing a uint8 by a uint8 is going to give you another integer, s...

4 years ago | 0

Answered

How to interpolate for given inputs in a n*m matrix

If I understand your question correctly, it sounds like <http://www.mathworks.com/help/matlab/ref/griddedinterpolant-class.html ...

How to interpolate for given inputs in a n*m matrix

If I understand your question correctly, it sounds like <http://www.mathworks.com/help/matlab/ref/griddedinterpolant-class.html ...

4 years ago | 0

| accepted

Answered

Why is MATLAB crashing on medium-to-large matrices?

Does it create a crash log? If so, what's in the log? You can find it using the directions located here: <http://www.mathwo...

Why is MATLAB crashing on medium-to-large matrices?

Does it create a crash log? If so, what's in the log? You can find it using the directions located here: <http://www.mathwo...

4 years ago | 0

Answered

How to realzie iczt use Matlab?

There's not necessarily going to be a straightforward inverse for the Chirp-Z transform unless its parameters define evenly spac...

How to realzie iczt use Matlab?

There's not necessarily going to be a straightforward inverse for the Chirp-Z transform unless its parameters define evenly spac...

4 years ago | 1

Answered

How do I reduce this nxmx3 matrix to a (n*m)x3 matrix?

It sounds like you want a combination of <http://www.mathworks.com/help/matlab/ref/permute.html permute> and <http://www.mathwor...

How do I reduce this nxmx3 matrix to a (n*m)x3 matrix?

It sounds like you want a combination of <http://www.mathworks.com/help/matlab/ref/permute.html permute> and <http://www.mathwor...

4 years ago | 0

| accepted

Answered

Combine datasets of unequal lengths by matching dates

There's a little bit of ambiguity here, but this shouldn't be too hard. What happens when there is no corresponding date from V...

Combine datasets of unequal lengths by matching dates

There's a little bit of ambiguity here, but this shouldn't be too hard. What happens when there is no corresponding date from V...

4 years ago | 0