TApply: Applies a transformation object on a StQ or data.table.

In Luis-Sanguiao/StQT: Transformation of Standard Questionnaires

Description

TApply returns a transformed object according to the transformation rules.

Usage

TApply(x, Tr)

## S4 method for signature 'data.table,StQT'
TApply(x, Tr)

## S4 method for signature 'StQ,StQT'
TApply(x, Tr)

Arguments

x	Object of class StQ or data.table with data to transform
Tr	Object of class StQT with the transformation we are going to apply.

Details

There are three kinds of transformation rules: internal functions, row insertion and column insertion.

• Internal functionsFunDelRow, FunDelVar and FunAutoLink so far. The first one deletes rows in domain. The second one deletes the variables specified in the output. The third one copies the input variables from the table linking according to the expression in domain.

• Row insertionRow are inserted. This kind of rule is applied when there exists an assignment in the output. Unassigned variables are calculated according output = fun(input). Any variable included in by is copied into the new rows.

• Column insertionRows are calculated according output = fun (input)

Parameter domain specifies the subset of the dataset where we are going to do the calculation. Parameter by sets the variables where we are applying the rule by. Parameter order orders the table, previously to apply the transformation. Parameter key (irrelevant for data.table) sets which of the variables are qualifiers.

Value

StQ or data.table respectively with transformed data

Examples

require(data.table)
dt <- data.table(Region = c("1","2","3"), GDP = c(1.38,0.94,1.23))
dt
T1 <- NewStQT(data.frame(
  output = "Region='Total',GDP",
  fun = "sum",
  input = "GDP",
  stringsAsFactors = FALSE))
TApply(dt,T1)
require(StQ)
data(ExampleStQ)
rules <- data.frame(domain = c('','Turnover > 0'),
                    output = c('AggTurnover','LogTurnover'),
                       fun = c('sum','log'),
                     input = c('Turnover','Turnover'),
                        by = c('NACE09',''),
                       key = c('NACE09',''),
                         stringsAsFactors = FALSE)
T2 <- NewStQT(rules)
(ExampleStQ2 <- TApply(ExampleStQ,T2))

Luis-Sanguiao/StQT documentation built on May 7, 2019, 2:03 p.m.