Is there a way to set the zorder of each dataset in a multiple bar graph different at each x location so that all of the information is visible.

```
axes.bar(position,data_1,color='g')
axes.bar(position,data_2,color='r')
axes.bar(position,data_3,color='b')

```

for example, if a blue value is greater than a green value the green will be hidden behind and visa versa. setting alpha to lower values than one creates more than 3 colors displayed from mixing of colors.