17 lines
629 B
Matlab
17 lines
629 B
Matlab
function q = quartiles( x )
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% returns a vector with the first, second, and third quartile
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% of the vector x
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xs = sort( x );
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if ( length( xs ) == 0 ) % no data
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q = [];
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elseif ( rem( length( xs ), 2 ) == 0 ) % even number of data
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index = length( xs )/2;
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m = (xs( index ) + xs( index+1 ))/2;
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q = [ round( xs(length(xs)/4) ), m, xs(round(3*length(xs)/4)) ];
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else % odd number of data
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index = (length( xs ) + 1)/2;
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m = xs( index );
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q = [ round( xs(length(xs)/4) ), m, xs(round(3*length(xs)/4)) ];
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end
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end
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