# Peng Li

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**Content Feed**

Bug in TabGroup appearance in AppDesigner (R2019b)

Had the same issue in 2022a. I have worked out a temporal solution. What I did that can show the right selection was that in the...

7 months ago | 0

Question

why does fitlme with a random effect gives the same results to fitlme without the random effect

considering the data attached. tbl = readtable('t.txt'); mdl1 = fitlme(tbl, 'y ~ g + (1|match)') mdl2 = fitlme(tbl, 'y ~ g'...

2 years ago | 1 answer | 0

### 1

answerQuestion

which tree node fires a context menu

I have a specific question about the context menu for uitree. It seems that there is no way to identify within the ContextMenuOp...

2 years ago | 0 answers | 1

### 0

answersLinear mixed models not working

In your first equation with random effect, you see that the random effect estimate is 0. If you check your data, you will find o...

3 years ago | 0

how to detemine this residual matrix ?

Interesting. This is an application of the detrended fluctuation analysis (DFA) to a 2D image. Based on what your screenshot sho...

3 years ago | 0

Finding RRI fluctuations (ECG) in 1s windows

Your question isn't quite clear. If you want to get fluctuations of subsequent points in a time series as you described above, y...

3 years ago | 0

Prevent colorbar label overlapping with subplots axis

You can specify the Position property of each Axes to the position you'd like it to be at, instead of using subplot. I found thi...

3 years ago | 0

How to add " significant star " (*) to errorbar plot ?

This can be added using text function. You simply fake it using text label. For example, text(x, y, '$\asterisk$', 'Interpretati...

3 years ago | 1

Logistic mixed-effect regression example

You could use fitglme now to fit mixed effect logistic regression models. You can specify the distribution as Binomial and this ...

3 years ago | 2

Mixed terms and fitlmematrix

For new versions of MATLAB, you can use fitlm, fitlme, fitglme which allows table input, and allows formulas. But if you use fi...

3 years ago | 0

Mixed effect linear regression model with multiple independent observations

Also found this old post related to LME. Below is my opion for future readers. My interpretation of the output: The CNR decrea...

3 years ago | 0

| accepted

Mixed-effect regression with repeated measures

This is also an old post now. I guess what the author of this post meant to use subject as a random effect, not a fixed effect, ...

3 years ago | 0

How can I fit a linear mixed-effects model with only quadratic/second-order terms?

This is an old post now. Just for future readers, you can explicitly get rid of any items you don't want by minus it. For the qu...

3 years ago | 0

How to interpret FFT output signal?

Based on your code, your sampling frequency is 1/3 Hz. There is no way you can detect a component of 0.316 Hz using 1/3 Hz sampl...

3 years ago | 0

Which formula fits better for this Linear Mixed-Effects Model?

To understand your dataset, I still believe that descriptive statics can give you the broad general picture. In terms of statist...

3 years ago | 0

readtable with multiple date formats

A workaround for me I think is to just load that column in string format. After loading you can do some cleaning before you conv...

3 years ago | 0

Averaging subsets of a large dataset

You can load this datasheet to matlab using readtable. after that, you have a table variable that allows easier manipulation. T...

3 years ago | 1

| accepted

Integrate kernel probability distribution function

https://www.mathworks.com/help/matlab/ref/trapz.html trapz is a function that deals with numerical integration. Check the above...

3 years ago | 0

LME and multiple comparisons

If I understand your question correctly, you were asking a post hoc comparison issue? coefTest method of LinearMixedModel object...

3 years ago | 0

I am looking for a function in R that can help me deal with the different structures of the variance-covariance matrix. And thank you in advance

are you looking for solutions in MATLAB or in R? This is the community for MATLAB. and get back to your question, fitlme or fit...

3 years ago | 0

| accepted

Question

speed up renamecats/categorical multiple columns

I have a huge csv file of about 16GB which over 9k columns. Each column is initially filled with some codes (either integer or s...

3 years ago | 1 answer | 0

### 1

answerExtracting and plotting max/min values from timeseries

Better take advantage of table format and splitapply function. tbl = readtable('data.csv'); tbl.day = day(tbl.Date); tbl.h...

3 years ago | 0

| accepted

What does the ' symbol mean?

transpose. https://www.mathworks.com/help/matlab/ref/transpose.html

3 years ago | 0

Question

datastore readsize and buffer chunk

I am working with a single csv file of over 10G size. I'm trying to use mapreduce to perform some analyses. The program works as...

3 years ago | 1 answer | 0

### 1

answerHow can i get contour plot like this?

https://www.mathworks.com/help/matlab/ref/contourf.html This might be what you need.

3 years ago | 1

| accepted

Can some one please tell me how to find the maximum amplitude frequency of the ecg signal? I have attached below my code. I keep getting maximum frequency at 0 Hz.

try Y = fft(ecgData - mean(ecgData), NFFT); It is expected that the DC contains most of the energy of the signal. You could e...

3 years ago | 0

| accepted

Having trouble with legend

Try this %Line Colors strColor = {'-r','-g','-b'}; %Legend String strLegend = {'nSamples = 5','nSamples = 10','nSamples = 15...

3 years ago | 0

convert a double matrix in cell within a table

t = table([ones(1, 4); ones(1, 4)*2; ones(1, 4)*3]) t = 3×1 table Var1 ________________ 1...

3 years ago | 1

| accepted

Finding average of a large csv file

why do you need a loop? you said you have ONE cvs file with 1 column and 301 rows? you just need to import the cvs file and do t...

3 years ago | 0

Indices of the values for which two conditions are true

tbl = table(abbrev(:), firstword(:), number(:)); [gp, outTbl] = findgroups(tbl(:, 1:2)); outTbl.sum = splitapply(@sum, tbl.(3)...

3 years ago | 0

| accepted