MATLAB: Does “rowfun” preallocate a table

MATLABmemoryrowfun

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"rowfun" already preallocates a table based on the input. This can be observed by inspecting the implementation of "rowfun":

>> edit rowfun.m

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MATLAB: Does the app freeze when loading data to a Table in App Designer and MATLAB R2017b

This issue does not occur in MATLAB R2018a.

To workaround this issue in MATLAB R2017b, add some "pause" statements:

>> app.StartButton.UserData='stopped';
>> pause(1);
>> view(app.AnimAxes, 30,2)
>> pause(1);
>>
>> LoadData(app);
>> pause(1);
>> app.Brake_Table.Data(:,1) = app.Data11;
>> app.Brake_Table.Data(:,2) = app.Data12;
>> pause(1);
>> app.Brake_Table_2.Data(:,1) = app.Data21;
>> app.Brake_Table_2.Data(:,2) = app.Data22;
>> pause(1);
>>
>> app.ax_Carposplot.XLim = [0 10];
>> app.ax_Carvplot.XLim = [0 10];
>> app.ax_Caraplot.XLim = [0 10];
>> app.ax_SCplot.XLim = [0 10];
>> app.ax_SCplot.YLim = [-0.2 1.2];
>> app.ax_SCplot.YTick = [0 1];
>> app.ax_SCplot.YTickLabel = {'open', 'closed'};

MATLAB: How do you split a table into sub-tables based on entries in a specific column

I have created a simple example which demonstrates how to split a table based on the first column as the category variable.

The script is also attached as "test_script.m". Please read the comments to get a better understanding of how to use the script for your use case.

% Patient pateint data
load patients

% Create test table
T = table(Gender(1:5), Height(1:5), 'VariableNames', {'Gender', 'Height'});

% Group based on first column - gender column
% Modify 1 to appropriate column number
G = findgroups(T{:, 1});

% Split table based on first column - gender column
T_split = splitapply( @(varargin) varargin, T , G);

% Allocate empty cell array fo sizxe equal to number of rows in T_Split
subTables = cell(size(T_split, 1));

% Create sub tables
for i = 1:size(T_split, 1)
    subTables{i} = table(T_split{i, :}, 'VariableNames', ... 
                        T.Properties.VariableNames);
end

% Display Results
disp('Full Table:');
disp(T);
disp('Sub Table 1:');
disp(subTables{1});
disp('Sub Table 2:');
disp(subTables{2});

See this documentation for another example of using 'splitapply':

https://www.mathworks.com/help/matlab/matlab_prog/split-table-data-variables-and-apply-functions.html

Here is a list of the functions I am using:

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

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

Best Answer

Related Solutions

MATLAB: Does the app freeze when loading data to a Table in App Designer and MATLAB R2017b

MATLAB: How do you split a table into sub-tables based on entries in a specific column

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