ecdfSteps function

ecdfSteps

Compute Coordinates of an Empirical Distribution Function

ecdfSteps(x, extend)

Arguments

• x: numeric vector, possibly with NAs that are ignored
• extend: a 2-vector do extend the range of x (low, high). Set extend=FALSE to not extend x, or leave it missing to extend it 1/20th of the observed range on other side.

Returns

a list with components x and y

Details

For a numeric vector uses the R built-in ecdf function to compute coordinates of the ECDF, with extension slightly below and above the range of x by default. This is useful for ggplot2 where the ECDF may need to be transformed. The returned object is suitable for creating stratified statistics using data.table and other methods.

Examples

ecdfSteps(0:10)
## Not run:

# Use data.table for obtaining ECDFs by country and region
w <- d[, ecdfSteps(z, extend=c(1,11)), by=.(country, region)]  # d is a DT
# Use ggplot2 to make one graph with multiple regions' ECDFs
# and use faceting for countries
ggplot(w, aes(x, y, color=region)) + geom_step() +
       facet_wrap(~ country)
## End(Not run)

See Also

stats::ecdf()

Author(s)

Frank Harrell