| dstats {prettyR} | R Documentation |
calculates mean, variance or standard deviation and n for numeric variables
dstats(x,indices=NA,do.sd=FALSE)
x |
data frame, matrix or vector containing numeric variables |
indices |
which columns of the data frame or matrix to use |
do.sd |
logical - return standard deviation rather than variance |
dstats will accept a vector, matrix or data frame. It calculates the
mean, variance and valid n for the columns specified by indices.
If indices is not specified, it will be calculated for the
columns that return TRUE from as.numeric. If do.sd
is TRUE, it returns standard deviations rather than variances. Valid ns are
calculated as the number of observations that are NOT NA.
A matrix of three rows with the number of columns equal to the number of variables used.
Mean |
the results of applying the mean function |
Variance or SD |
the results of applying the var function
or the square root of that if do.sd is TRUE |
n |
the number of observations that are NOT NA |
Jim Lemon
test.df<-data.frame(A=sample(1:100,20),B=rnorm(20),C=sample(LETTERS,20)) dstats(test.df)