How to save an unknowm amount of matrixes? How to make boxplots of an unknown amount of matrixes?

% The script already functions but is there a kind of dynamic way to solve the problem? % The MatrixFGF5TBX3 is a valuesx2 Matrix % The Goal is to sort the Values of first row of the Matrix. The Point is, that the rows of the Matrix correspond to each other and are not allowed to be shuffled. The result should look like this:

0  21
0  2
0  1
1  0
1  32

% The next step is to create boxplots from the second column of the Matrix. But all in one graph! % I saved the sorted blocks in a cell but how can I run the boxplots then? % A Further point is that the MatrixFGF5TBX3 looks different each time - so with my approach I would have to check the script every time

wenneinmaldurch = 0;
g=0;
Max = max(MatrixFGF5TBX3(:,1));
FinalMatrix = zeros(1,2);
Matrixa = zeros(1,2);
Matrixb = zeros(1,2);

for g=0:Max
Matrixa = MatrixFGF5TBX3(MatrixFGF5TBX3(:,1)== wenneinmaldurch,:);
Matrixb = cat(1,FinalMatrix,Matrixa);
FinalMatrix = Matrixb;
wenneinmaldurch = wenneinmaldurch +1;
g = g+1;
end

wenneinmaldurch =0;
h=0;
k = 1;
TBX3Matrix = cell(Max,1);

for h =0:Max

TBX3Matrix{k} = FinalMatrix(FinalMatrix(:,1)==wenneinmaldurch,:);

wenneinmaldurch =wenneinmaldurch+1;
h=h+1; k = k+1;
end

figure;
x1 = TBX3Matrix{1}; x2 = TBX3Matrix{2}; x3 = TBX3Matrix{3};x4 = TBX3Matrix{4};x5 = TBX3Matrix{5}; x6 = TBX3Matrix{6};x7 = TBX3Matrix{7};x8 = TBX3Matrix{8};x9 = TBX3Matrix{9};x10 = TBX3Matrix{10};x11 = TBX3Matrix{11};x12 = TBX3Matrix{12};x13 = TBX3Matrix{13};x14 = TBX3Matrix{14};x15 = TBX3Matrix{15};x16 = TBX3Matrix{16};x17 = TBX3Matrix{17};x18 = TBX3Matrix{18};x19 = TBX3Matrix{19};x20 = TBX3Matrix{20};x21 = TBX3Matrix{21};x22 = TBX3Matrix{22};x23 = TBX3Matrix{23};x24 = TBX3Matrix{24};x25 = TBX3Matrix{25};x26 = TBX3Matrix{26};x27 = TBX3Matrix{27};x28 = TBX3Matrix{28};x29 = TBX3Matrix{29};x30 = TBX3Matrix{30};x31 = TBX3Matrix{31};x32 = TBX3Matrix{32};x33 = TBX3Matrix{33};x34 = TBX3Matrix{34};x35 = TBX3Matrix{35};x36 = TBX3Matrix{36};x37 = TBX3Matrix{37};x38 = TBX3Matrix{38};x39 = TBX3Matrix{39};x40 = TBX3Matrix{40};x41 = TBX3Matrix{41};
x1 = x1(:,2);x2 = x2(:,2);x3 = x3(:,2);x4 = x4(:,2);x5 = x5(:,2);x6 = x6(:,2);x7 = x7(:,2);x8 = x8(:,2);x9 = x9(:,2);x10 = x10(:,2);x11 = x11(:,2);x12 = x12(:,2);x13 = x13(:,2);x14 = x14(:,2);x15 = x15(:,2);x16 = x16(:,2);x17 = x17(:,2);x18 = x18(:,2);x19 = x19(:,2);x20 = x20(:,2);x21 = x21(:,2);x22 = x22(:,2);x23 = x23(:,2);x24 = x24(:,2);x25 = x25(:,2);x26 = x26(:,2);x27 = x27(:,2);x28 = x28(:,2);x29 = x29(:,2);x30 = x30(:,2);x31 = x31(:,2);x32 = x32(:,2);x33 = x33(:,2);x34 = x34(:,2);x35 = x35(:,2);x36 = x36(:,2);x37 = x37(:,2);x38 = x38(:,2);x39 = x39(:,2);x40 = x40(:,2);x41 = x41(:,2);
x = [x1;x2;x3;x4;x5;x6;x7;x8;x9;x10;x11;x12;x13;x14;x15;x16;x17;x18;x19;x20;x21;x22;x23;x24;x25;x26;x27;x28;x29;x30;x31;x32;x33;x34;x35;x36;x37;x38;x39;x40;x41];
g = [ones(size(x1));2*ones(size(x2));3*ones(size(x3));4*ones(size(x4));5*ones(size(x5));6*ones(size(x6));7*ones(size(x7));8*ones(size(x8));9*ones(size(x9));10*ones(size(x10));11*ones(size(x11));12*ones(size(x12));13*ones(size(x13));14*ones(size(x14));15*ones(size(x15));16*ones(size(x16));17*ones(size(x17));18*ones(size(x18));19*ones(size(x19));20*ones(size(x20));21*ones(size(x21));22*ones(size(x22));23*ones(size(x23));24*ones(size(x24));25*ones(size(x25));26*ones(size(x26));27*ones(size(x27));28*ones(size(x28));29*ones(size(x29));30*ones(size(x30));31*ones(size(x31));32*ones(size(x32));33*ones(size(x33));34*ones(size(x34));35*ones(size(x35));36*ones(size(x36));37*ones(size(x37));38*ones(size(x38));39*ones(size(x39));40*ones(size(x40));41*ones(size(x41));];
 boxplot(x,g);

[Stephen23]

The answer is really simple: don't.

Whenever you find yourself doing thing like this:

x1 = TBX3Matrix{1}; x2 = TBX3Matrix{2}; x3 = TBX3Matrix{3};x4 = TBX3Matrix{4};x5 = TBX3Matrix{5}; x6 = TBX3Matrix{6};x7 = TBX3Matrix{7};x8 = TBX3Matrix{8};x9 = TBX3Matrix{9};x10 = TBX3Matrix{10};x11 = TBX3Matrix{11};x12 = TBX3Matrix{12};x13 = TBX3Matrix{13};x14 = TBX3Matrix{14};x15 = TBX3Matrix{15};x16 = TBX3Matrix{16};x17 = TBX3Matrix{17};x18 = TBX3Matrix{18};x19 = TBX3Matrix{19};x20 = TBX3Matrix{20};x21 = TBX3Matrix{21};x22 = TBX3Matrix{22};x23 = TBX3Matrix{23};x24 = TBX3Matrix{24};x25 = TBX3Matrix{25};x26 = TBX3Matrix{26};x27 = TBX3Matrix{27};x28 = TBX3Matrix{28};x29 = TBX3Matrix{29};x30 = TBX3Matrix{30};x31 = TBX3Matrix{31};x32 = TBX3Matrix{32};x33 = TBX3Matrix{33};x34 = TBX3Matrix{34};x35 = TBX3Matrix{35};x36 = TBX3Matrix{36};x37 = TBX3Matrix{37};x38 = TBX3Matrix{38};x39 = TBX3Matrix{39};x40 = TBX3Matrix{40};x41 = TBX3Matrix{41};

you need to write much better code by using a loop and indexing, or even better by writing vectorized code. That is all there is to it.

[Philipp Fischer]

I know about that problem. A kind of that was my question I wanted to know about more. How can I ride there a loop?

[Stephen23]

The functions cellfun and arrayfun get the values you want, without any loop (untested code):

C = cellfun(@(m)m(:,2),TBX3Matrix,'UniformOutput',false)
X = vertcat(C{:})
N = cellfun('size',TBX3Matrix,1);
D = arrayfun(@(n,x)x*ones(n,1),N(:)',1:numel(TBX3Matrix),'UniformOutput',false)
G = vertcat(D{:})
boxplot(X,G)

Answer 1

[Stephen23]

https://www.mathworks.com/help/matlab/matlab_prog/string-evaluation.html

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

[Philipp Fischer]

Thanks Stephen Cobeldick for your fast answer,

 so you would suggest that my approach is for a beginner the best way?
And you would recommend in learning more about numeric arrays?

Thank you for your help.

[Stephen23]

"you would suggest that my approach is for a beginner the best way"

No. For example you have written lots of numbered variables and copied-and-pasted code hundreds of times to create things like this:

x1 = x1(:,2);x2 = x2(:,2);x3 = x3(:,2);x4 = x4(:,2);x5 = x5(:,2);x6 = x6(:,2);x7 = x7(:,2);x8 = x8(:,2);x9 = x9(:,2);x10 = x10(:,2);x11 = x11(:,2);x12 = x12(:,2);x13 = x13(:,2);x14 = x14(:,2);x15 = x15(:,2);x16 = x16(:,2);x17 = x17(:,2);x18 = x18(:,2);x19 = x19(:,2);x20 = x20(:,2);x21 = x21(:,2);x22 = x22(:,2);x23 = x23(:,2);x24 = x24(:,2);x25 = x25(:,2);x26 = x26(:,2);x27 = x27(:,2);x28 = x28(:,2);x29 = x29(:,2);x30 = x30(:,2);x31 = x31(:,2);x32 = x32(:,2);x33 = x33(:,2);x34 = x34(:,2);x35 = x35(:,2);x36 = x36(:,2);x37 = x37(:,2);x38 = x38(:,2);x39 = x39(:,2);x40 = x40(:,2);x41 = x41(:,2);

There are much much simpler, faster, and neater ways of doing this. Computers are good at doing one thing: the same task, repeatedly. So why are you doing the computer's work? Just write a loop, or even better learn how to write vectorized code.