ffbase (version 0.6-2)

binned_sumsq: Fast summing in different bins

Description

binned_sum implements fast squared summing for given bins by calling c-code, which can be used to calculate variance and standard deviation Please note that incorrect use of this function may crash your R-session. the values of bins must be in between 1:nbins and bin may not contain NA

Usage

binned_sumsq(x, mean = rep(0, nbins), bin,
    nbins = max(bin))

  ## S3 method for class 'ff':
binned_sumsq(x, bin, nbins=max(bin), ...)

Arguments

x

numeric vector with the data to be summed squared

mean

numeric vector with an optional mean to be subtracted from the data to be summed and squared

bin

integer vector with the bin number for each observation

nbins

integer maximum bin number

...

passed on to chunk

Value

• numeric matrix where each row is a bin