Dot plot rather than scatter plot

Give a dot plot rather than scatter plot by Taorong Xie([e-mail]), 2011

Give a dot plot for one data group. It could rerun the function by changing the 'data' and 'groupNum' for multi-group. It should run the function one times for each group, and they will show in the same diagram. The dot plot could also combine with box plot.

Syntax
dotPlot_xtr( data )
dotPlot_xtr( data,groupNum )
dotPlot_xtr( data,groupNum,thres )
dotPlot_xtr( data,...,moveStep )
Description
data -- data of one group
groupNum -- the x-position of this data group. Defaut value: 1
thres -- the maximum ratio of every two data's split to mean value which can stay in the same column (x-position). Defaut value: 0.1
moveStep -- the distance of each column. Defaut value: 0.05