MATLAB: Boxplot of correlation values from a cell array

cell arrayscorrelation

Before describing my question I provided the following code, which help me in describing what I'm trying to do:
clear all
AirT = {rand(32,1),rand(32,1),rand(32,1),rand(32,1)};
SolRad = {rand(32,1),rand(32,1),rand(32,1),rand(32,1)};
Rain = {rand(32,1),rand(32,1),rand(32,1),rand(32,1)};
Location = {'England','Wales','Scotland','Ireland'};
points = {1,2,2,2};
CorrVariables = {'AirT','SolRad','Rain'};
for i = 1:length(Location);
    Data = @(location) struct('Location',location,CorrVariables{1},AirT{i},...
        CorrVariables{2},SolRad{i},CorrVariables{3},Rain{i});
    D(i) = Data(Location{i});
end
FieldName = {D.Location};
R = corrcoef([D.AirT],'rows','pairwise');
R_Value = [Location(nchoosek(1:size(R,1),2)) num2cell(nonzeros(tril(R,-1)))];
q = points(nchoosek(1:size(R,1),2));
    %to calculate the combination of these points we need to convert the
    %cell into a matrix.
qq = cell2mat(q);
    %calculate
qq = qq(:,1)+qq(:,2);
    %insert into R_Values in the last row.
Re = [R_Value num2cell(qq)];
The code above is not really important but the output provides a better explanation than what I can give.
So, in 'Re' we have the name of the pairs (Re(:,1:2)) of data used in calculating the correlation coefficient (Re(:,3)) and then the combination of the points assigned to each pair (Re(:,4)).
From this I hope to produce a boxplot which shows the correlation values of those pairs with points = 3 in one box and another box showing the correlation values of the pairs with points = 4.
How would I go about doing this?

Best Answer

boxplot(cell2mat(Re(:,3)),Re(:,4))
This first input argument is the data, and the second input argument is the "grouping variable" that indicates the data categories.
See
doc boxplot
for details.
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