This function computes the d statistic that is defined in:
Cliff, N. (1993).  Dominance statistics:  Ordinal analyses to answer ordinal
questions.  Psychological Bulletin, 114(3), 494-509.
d estimates P(X > Y) - P(X < Y).  Optionally, the function
computes other useful statistics like variance estimates.
Arguments & Output:
'x', 'y' are vectors of data.
If 'missing.allowed = TRUE', missing values are removed from 'x' and 'y'
prior to computing results.  If 'missing.allowed = FALSE', then the function
halts with an error message.
If 'all.stats = TRUE', the following additional statistics are computed:
's2.nonneg' is a biased estimate of Var(d) using a correction suggested
by Cliff (1993) that prevents negative values of the variance estimate.
's2.unbiased' is the unbiased estimate of Var(d).  In rare situations, it can
be negative.
'min.possible' is the minimum possible value of Var(d).  's2.nonneg' is
the maximum of 's2.unbiased' and 'min.possible'.
's2.x.dot', 's2.y.dot', and 's2.ij' are the estimated variances of
the 'x', 'y', 'xy' components.
'n.x' and 'n.y' are the 'x' and 'y' sample sizes after removal of missing
values if any were present.

'cnv.bytes' converts between different units of bytes.  Simply
specify the 'bytes', 'kilobytes', 'megabytes', or 'gigabytes'
argument, and the quantity in the other units will be outputted.

'col.ranges' returns the numeric codes for ranges of columns that are designated by column names, e.g., if xx is a matrix or dataframe with names, 'a', 'b', 'c', ..., 'z', then col.ranges(xx, from = 'b', to = 'e') returns 2:5.  'col.ranges' also operates on multiple ranges, e.g., col.ranges(xx, from = c('b', 'm', 'u'), to = c('e', 'p', 'x')) returns c(2:5, 13:16, 21:24).  It should also work with a vector with named elements.

The colorChart function makes a plot showing colors that are available in R and the correspondence between these colors and number codes for the colors.  

The colorChart function adopts code that is due to Earl F. Glynn, Stowers Institute for Medical Research.  His code has been modified in minor ways and it has been combined into the colorChart function.  See http://research.stowers-institute.org/efg/R/Color/Chart/index.htm
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ARGUMENT:

orderBy:  If orderBy = "number" (default), the colors are ordered by their code number; if orderBy = "hue", the colors are ordered by hue, saturation and value.