R: Basic statistical functions for ff

ffbase-package {ffbase} | R Documentation

## Basic statistical functions for ff

### Description

Basic statistical functions for `ff` vectors and `ffdf` data.frames. The aim of ffbase is to make working with ff vectors and ffdf data.frame a bit easier.

### Basic operations

`cut.ff` | cut a `ff` vector.
`c.ff` | concatenate `ff` vectors.
`unique` | unique for a `ff` vector and `ffdf`.
`duplicated` | duplicated for a `ff` vector and `ffdf`.
`ffmatch` | match for a 2 `ff` vectors.
`ffdfmatch` | match for 2 `ffdf` objects.
`%in%` | %in% operator for a `ff` vector and `ffdf`.
`is.na.ff` | is.na for a `ff` vector.
`+, -, *, /, ^, %%, %/%` | operators for arithmetic on `ff` vector.
`==, !=, <, <=, >=, >, &, |, !` | compare & logic operators for working with `ff` vectors.
`abs, sign, sqrt, ceiling, floor, trunc, round, signif` | Math operators for working on `ff` vectors.
`log, log10, log2, log1p, exp, expm1` | Math operators for working on `ff` vectors.
`acos, acosh, asin, asinh, atan, atanh` | Math operators for working on `ff` vectors.
`cos, cosh, sin, sinh, tan, tanh` | Math operators for working on `ff` vectors.
`gamma, lgamma, digamma, trigamma` | Math operators for working on `ff` vectors.

### Selections

`subset.ffdf` | subset a `ffdf`.
`transform.ffdf` | create a new `ffdf` based on an existing `ffdf`
`with.ffdf` | create a ff vector based on columns of an existing `ffdf`
`within.ffdf` | create a `ffdf` data.frame based on columns of an existing `ffdf`
`ffwhich` | create a `ff` integer vector based on a logical expression

### Aggregations

`hist.ff` | Calculate a histogram for `ff` vector.
`quantile.ff` | Get quantiles for `ff` vector.
`sum.ff` | sum for a `ff` vector.
`mean.ff` | (trimmed) mean for a `ff` vector.
`all.ff` | all for logical `ff` vector.
`min.ff` | min for `ff` vector.
`max.ff` | max for `ff` vector.
`cumsum.ff` | cumsum for `ff` vector.
`cumprod.ff` | cumprod for `ff` vector.
`range.ff` | range for `ff` vector.
`table` | table for `ff` vectors.
`tabulate.ff` | tabulate for `ff` vectors.
`ffdfdply` | Split, group and aggregate for `ffdf` operations.

### Miscellaneous

`ffordered` | Add a sorted index to a `ff` vector.
`save.ffdf` | Save a `ffdf` in a directory with its containing `ff` columns.
`load.ffdf` | Loads a `ffdf` from a directory
`pack.ffdf` | Packs ffdf data.frames into a zip or tar file
`unpack.ffdf` | Unpacksdata.frames from a zip or tar file
`ffappend` | Append data to a `ff` vector.
`ffdfappend` | Append data to a `ffdf`.
`merge.ffdf` | Merge two `ffdf` objects.
`ffmatch` | match two ff vectors
`ffdfmatch` | match two ffdf data.frames
`laf_to_ffdf` | Import csv and fixed width files through package LaF.

### Examples

    ffdat <- as.ffdf(data.frame(x=1:10, y=10:1))

    # add a new ff vector z to the ffdf data.frame
    within(ffdat, {z <- x+y})[]

    # add a new ff vector z to the ffdf data.frame using transform
    transform(ffdat, z=x+y)[]

    cut(ffdat$x, breaks=3)[]

    tabulate.ff(ffdat$x)

[Package ffbase version 0.13.1 Index]