Hello Laurence,
I understand that you would like the box plot to be a little more easily viewed, both in box width and box spacing.
The former issue can be resolved by specifying the 'widths' argument in the boxplot function. Since there is a different amount of spacing between each line, it is probably best to specify the box widths differently for each data point based on that spacing (so long as it is understood that box width is not representing data differently).
The latter issue can be resolved by viewing the plot with a logarithmic scale on the x-axis. This will space out the data points more evenly, though there is now a little clustering in the higher valued regions.
KDgaps = diff(KD_values)/2;
boxplot(M,'positions',KD_values,'widths',[KDgaps(1) KDgaps])
set(gca,'XScale','log')
I hope this helps!
-Cam
