GetPooledSTD.m

function PooledSTD = GetPooledSTD( nVector, stdVector )

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    %Method Description:
    %-------------------
    %
    %calculate the pooled variance by a vector of standard deviations 
    %'stdVector' and the corresponding number of values used to calculate
    %the std's given by 'nVector'
    
    if  numel(nVector) ~= numel(stdVector) || ...
        max(isnan(nVector)) > 0 || ...
        max(isnan(stdVector)) > 0
            %Print warning to command, return "nan"
            Error('WARNING: Wrong inputs for "nVector" and/or "stdVector"!')
            PooledSTD = nan;    
    else
        %Weighted average of the n sample variances
        PooledSTD = sqrt(sum( (nVector - 1) .* stdVector.^2) / ( sum(nVector - 1) ));

    end   

end