Implement split stems in stemplots #2
Description
When there are a large number of observations, it can be helpful to split the stems in a stem-and-leaf plot so that one has leaves 0-4 and another 5-9. The stem-size argument could be used to implement this without too much difficulty by keeping track of the 'base' stem and adjusting the print. E.g. use a stem-size of 5, but print each stem twice and adjust the leaf size (currently hard-coded to 1).