Package 'sasif'

Title: 'SAS' IF Style Data Step Logic for Data Tables
Description: Provides 'SAS'-style IF/ELSE chains, independent IF rules, and DELETE logic for 'data.table', enabling clinical programmers to express Study Data Tabulation Model (SDTM) and Analysis Data Model (ADaM)-style derivations in familiar SAS-like syntax. Methods are informed by clinical data standards described in CDISC SDTM and ADaM implementation guides. See <https://www.cdisc.org/standards/foundational/sdtm> and <https://www.cdisc.org/standards/foundational/adam>.
Authors: Thiyagarajan Chandrasekaran [aut, cre]
Maintainer: Thiyagarajan Chandrasekaran <[email protected]>
License: MIT + file LICENSE
Version: 0.1.2
Built: 2026-05-20 09:40:25 UTC
Source: https://github.com/chandrt23-lang/sasif

Help Index

SAS IF-style data step logic for data.table

Description

Provides SAS-style IF/ELSE chains, independent IF rules, and DELETE logic for fast, vectorized transformations on data.table objects. This enables clinical programmers to express SDTM and ADaM-style derivations in familiar SAS-like syntax while leveraging data.table performance.

Usage

data_step(dt, ..., copy = TRUE)

Arguments

dt

A data.table.
...

One or more rule objects created by if_do(), else_if_do(), else_do(), if_independent(), or delete_if().
copy

Logical. If TRUE (default), a copy of dt is modified and returned.

Value

A data.table with applied transformations.

Examples

library(data.table)

dt <- data.table(
  AGE = c(40, 60, 80),
  SEX = c("M", "F", "M")
)

out <- data_step(
  dt,
  if_do(AGE <= 45, GROUP = 1),
  else_if_do(AGE <= 70, GROUP = 2),
  else_do(GROUP = 3),
  if_independent(SEX == "M", MALE = 1)
)

out

Create a SAS-style DELETE rule

Description

Creates a DELETE rule to remove rows from the data.table when condition is TRUE.

Usage

delete_if(condition)

Arguments

condition

Logical condition evaluated on the data.table.

Value

A rule object for data_step().

Create a SAS-style ELSE rule

Description

Creates an ELSE rule for use inside data_step().

Usage

else_do(...)

Arguments

...

Named assignments to apply when no previous IF/ELSE IF matched.

Value

A rule object for data_step().

Create a SAS-style ELSE IF rule

Description

Creates an ELSE IF rule for use inside data_step().

Usage

else_if_do(condition, ...)

Arguments

condition

Logical condition evaluated on the data.table.
...

Named assignments to apply when condition is TRUE.

Value

A rule object for data_step().

Create a SAS-style IF rule

Description

Creates a mutually exclusive IF rule for use inside data_step().

Usage

if_do(condition, ...)

Arguments

condition

Logical condition evaluated on the data.table.
...

Named assignments to apply when condition is TRUE.

Value

A rule object for data_step().

Create an independent SAS-style IF rule

Description

Creates an independent IF rule that is evaluated regardless of IF/ELSE chains.

Usage

if_independent(condition, ...)

Arguments

condition

Logical condition evaluated on the data.table.
...

Named assignments to apply when condition is TRUE.

Value

A rule object for data_step().