This functions computes the absolute coefficient of variation as proposed by Pearson: standard deviation divided by the mean. Essentially, cv reflects a normalized measure of dispersion of a probability distribution. Distributions with cv < 1 are considered low-variance, while those with cv > 1 high-variance.
is a numeric vector.
sd(x)/mean(x) = cv, which is the inverse of signal-to-noise ratio.
Will return the computation of the variation.