Stem and leaf plot

Stem and leaf plot. Will accept a factor variable as a second argument to create stem plots for each of the levels.

Usage

stemPlot(x, ...)

# Default S3 method
stemPlot(x, grpvar = NULL, varname = NULL, grpvarname = NULL, ...)

# S3 method for class 'formula'
stemPlot(formula, data = parent.frame(), subset, ...)

Arguments

x

a numeric variable.

...

further arguments to be passed to or from methods.

grpvar

a factor variable. A stem plot of x will be created for each level of the factor variable.

varname

name of the numeric variable. This is for printing the output only. Change if you want to print out a name different from the actual variable name.

grpvarname

name of the factor variable. This is for printing the output only. Change if you want to print out a name different from the actual variable name.

formula

a formula of the form x ~ grpvar where x is numeric and grpvar is a factor variable.

data

a data frame with the variables in the formula.

subset

an optional expression specifying which observations to keep.

Details

This command is just an enhanced version of R's stem command. It allows the user to create the stem plot for a numeric variable grouped by the levels of a factor variable.

Methods (by class)

• stemPlot(default): Stem and leaf plot

• stemPlot(formula): Stem and leaf plot

Author

Laura Chihara

Examples

stemPlot(states03$Births, states03$Region)
#> 
#> ***Stem and Leaf plot for  states03$Births ***
#>    Grouped by levels of  states03$Region 
#> 
#>     Midwest 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 11344
#>   0 | 7788
#>   1 | 3
#>   1 | 58
#> 
#> 
#>     Northeast 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 111114
#>   0 | 78
#>   1 | 14
#>   1 | 
#>   2 | 
#>   2 | 5
#> 
#> 
#>     South 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 244566678
#>   1 | 024
#>   2 | 1
#>   3 | 7
#> 
#> 
#>     West 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 111223345789
#>   2 | 
#>   4 | 2
#> 

stemPlot(Births ~ Region, data = states03)
#> 
#> ***Stem and Leaf plot for  Births ***
#>    Grouped by levels of  Region 
#> 
#>     Midwest 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 11344
#>   0 | 7788
#>   1 | 3
#>   1 | 58
#> 
#> 
#>     Northeast 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 111114
#>   0 | 78
#>   1 | 14
#>   1 | 
#>   2 | 
#>   2 | 5
#> 
#> 
#>     South 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 244566678
#>   1 | 024
#>   2 | 1
#>   3 | 7
#> 
#> 
#>     West 
#>  :
#>   The decimal point is 5 digit(s) to the right of the |
#> 
#>   0 | 111223345789
#>   2 | 
#>   4 | 2
#>