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...

12 Tage ago | 0 answers | 0

Answered

Extracting 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...

Extracting 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...

12 Tage ago | 0

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Answered

What does the ' symbol mean?

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

What does the ' symbol mean?

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

12 Tage ago | 0

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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...

13 Tage ago | 1 answer | 0

Answered

How can i get contour plot like this?

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

How can i get contour plot like this?

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

13 Tage ago | 1

| accepted

Answered

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...

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...

13 Tage ago | 0

| accepted

Answered

Having trouble with legend

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

Having trouble with legend

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

13 Tage ago | 0

Answered

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...

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...

13 Tage ago | 1

| accepted

Answered

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...

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...

13 Tage ago | 0

Answered

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)...

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)...

13 Tage ago | 0

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Answered

Help with Linear Mixed effects model formulas

For statistical questions, the first thing we ask is what the hypothesis is. From your equation, I guess you'd like to examine ...

Help with Linear Mixed effects model formulas

For statistical questions, the first thing we ask is what the hypothesis is. From your equation, I guess you'd like to examine ...

14 Tage ago | 0

Answered

How can i export data from an 'edit text box' in app designer to an excel file?

I assume that you have properties linked to each of these values. In the callback, you can create a structure or a table involv...

How can i export data from an 'edit text box' in app designer to an excel file?

I assume that you have properties linked to each of these values. In the callback, you can create a structure or a table involv...

15 Tage ago | 0

Answered

Is There a Way to Execute splitapply Functionality on Subtables of Master Table?

you'd better do this way: splitapply(@(x) sum(x, 1), T{:, 2:3}, G);

Is There a Way to Execute splitapply Functionality on Subtables of Master Table?

you'd better do this way: splitapply(@(x) sum(x, 1), T{:, 2:3}, G);

15 Tage ago | 0

Answered

HOW TO FIND THE R-SQUARED VALUE

mdl.Rsquared check https://www.mathworks.com/help/stats/linearmodel.html for properties and methods related to linear regressio...

HOW TO FIND THE R-SQUARED VALUE

mdl.Rsquared check https://www.mathworks.com/help/stats/linearmodel.html for properties and methods related to linear regressio...

15 Tage ago | 0

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Answered

What is the reference category in the output for a Fitlme with categorical variables and three-way interaction terms?

The table you copied isn't the default display from matlab, so it's difficult to tell anything from there. It's like an ANOVA ou...

What is the reference category in the output for a Fitlme with categorical variables and three-way interaction terms?

The table you copied isn't the default display from matlab, so it's difficult to tell anything from there. It's like an ANOVA ou...

15 Tage ago | 0

Question

Reduce function if concatenated intermediate results doesn't fit in memory

I'm trying to decode a huge dataset of rougly 500k*10k size. What I'm doing is actually load the file into a datastore, replace ...

16 Tage ago | 0 answers | 0

Answered

Reading EEG data downloaded from University of Bonn

This is a single channel EEG database. Each zip file has 100 txt files. Each txt file has 4096 samples . What does this mean ? ...

Reading EEG data downloaded from University of Bonn

This is a single channel EEG database. Each zip file has 100 txt files. Each txt file has 4096 samples . What does this mean ? ...

16 Tage ago | 0

| accepted

Answered

custom labels for errorplot

using annotation annotation('textbox', pos, 'String', str, 'FitBoxToText', 'on'); pos is the position where you want to put th...

custom labels for errorplot

using annotation annotation('textbox', pos, 'String', str, 'FitBoxToText', 'on'); pos is the position where you want to put th...

16 Tage ago | 0

| accepted

Answered

How to find the max value of amplitude in Fast Fourier Transform function?

I believe it is correct. you can always test it by plotting them. plot(freq, SSAS); hold on; plot(freq_max, SSAS_max, 'ro'); a...

How to find the max value of amplitude in Fast Fourier Transform function?

I believe it is correct. you can always test it by plotting them. plot(freq, SSAS); hold on; plot(freq_max, SSAS_max, 'ro'); a...

16 Tage ago | 0

Answered

MATLAB does not recognize the matrix

qlt_pts = u(kk) * score(kk); your score is a char array. so what do you want this multiplication to give you?

MATLAB does not recognize the matrix

qlt_pts = u(kk) * score(kk); your score is a char array. so what do you want this multiplication to give you?

16 Tage ago | 0

Answered

Converting these 5 lines of MATLAB code to C++?

As creating a vector that increments by 3. So is the first line creating an array of values that starts at one, increments by 2,...

Converting these 5 lines of MATLAB code to C++?

As creating a vector that increments by 3. So is the first line creating an array of values that starts at one, increments by 2,...

16 Tage ago | 0

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Answered

How can I check if a table contains numbers only?

I guess your question re the x-values isn't quite clear. For the first part of your question, it is tricky to determine whether...

How can I check if a table contains numbers only?

I guess your question re the x-values isn't quite clear. For the first part of your question, it is tricky to determine whether...

16 Tage ago | 1

| accepted

Answered

read table handling column of number values as column of strings

you could call detectImpactOptions first, and modify format from there before readtable. https://www.mathworks.com/help/matlab/...

read table handling column of number values as column of strings

you could call detectImpactOptions first, and modify format from there before readtable. https://www.mathworks.com/help/matlab/...

etwa ein Monat ago | 0

Answered

Incremental indexing to create an array

using diag(list_of_distances, -1) to get the diagonal you want.

Incremental indexing to create an array

using diag(list_of_distances, -1) to get the diagonal you want.

etwa ein Monat ago | 1

| accepted

Answered

audio extraction from individual/selective data column.

% it seems from the screenshot that your data is n by 2 matrix % thus length(data) only gives you n % endSample = length(data)...

audio extraction from individual/selective data column.

% it seems from the screenshot that your data is n by 2 matrix % thus length(data) only gives you n % endSample = length(data)...

etwa ein Monat ago | 0

| accepted

Answered

Sort a cell array based on average of one cell column/row, then sort the structure

I thought I answered this question... anyway, this is less clearer than the other one you asked. See example below % generated ...

Sort a cell array based on average of one cell column/row, then sort the structure

I thought I answered this question... anyway, this is less clearer than the other one you asked. See example below % generated ...

etwa ein Monat ago | 0

Answered

Export many data into the same excel file.

for i = 1 : nExtracted_files [data,samp_rate] = audioread(Extracted_files(i).name); % different files may have d...

Export many data into the same excel file.

for i = 1 : nExtracted_files [data,samp_rate] = audioread(Extracted_files(i).name); % different files may have d...

etwa ein Monat ago | 0

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Answered

Mean of cell array containing matrices

Not sure what do you mean by "re-sort the cell array according to the means" as you have two means corresponding to each cell. B...

Mean of cell array containing matrices

Not sure what do you mean by "re-sort the cell array according to the means" as you have two means corresponding to each cell. B...

etwa ein Monat ago | 0

| accepted

Answered

How to explore off diagonal elements in matrices without avoiding the for loop?

Not sure if many matrices share the same size. Anyway if you store these matrices in a cell you prob have a chance using cellfun...

How to explore off diagonal elements in matrices without avoiding the for loop?

Not sure if many matrices share the same size. Anyway if you store these matrices in a cell you prob have a chance using cellfun...

etwa ein Monat ago | 0

Answered

how do I convert this to a for loop

% your while loop x = input('Enter a number between 1 and 100: '); i = 0; while x>0 x=x-i; i=i+1; end fprintf('T...

how do I convert this to a for loop

% your while loop x = input('Enter a number between 1 and 100: '); i = 0; while x>0 x=x-i; i=i+1; end fprintf('T...

etwa ein Monat ago | 0

| accepted