matchesCriteria: Do Data Frame Row Match Given Criteria?

In KWB-R/kwb.utils: General Utility Functions Developed at KWB

Do Data Frame Row Match Given Criteria?

Description

are data frame rows matching given criteria?

Usage

matchesCriteria(
  Data,
  criteria = NULL,
  na.to.false = FALSE,
  add.details = FALSE,
  dbg = TRUE
)

Arguments

Data	data frame
criteria	vector of character containing conditions, in which the column names of Data, e.g. A can appear unquoted, e.g. "A == 'x'"
na.to.false	if TRUE (the default is FALSE) NA in the resulting vector will be replaced with FALSE
add.details	if TRUE (the default is FALSE) a matrix containing the evaluation of each criterion is returned in attribute details
dbg	if TRUE (default) for each criterion in criteria it is shown for how many rows in Data the criterion is TRUE and for how many rows it is FALSE

Value

vector of logical containing TRUE at positions representing rows in Data fulfilling the conditions and FALSE elsewhere

Examples

# Define an example data frame
Data <- data.frame(A = c("x", "y", "z", NA),
                   B = c( NA,   2,   3, 4))

# Define one or more criteria
criteria <- c("A %in% c('y', 'z')", "B %in% 1:3")

# For which rows the criteria are met (vector of logical)?
matchesCriteria(Data, criteria, dbg = FALSE)

# You may use the function in the context of indexing:
Data[matchesCriteria(Data, criteria), ]

# Filtering for non-NA values
D1 <- Data[matchesCriteria(Data, "! is.na(A) & ! is.na(B)"), ]

# the same result is returned by:
D2 <- Data[matchesCriteria(Data, c("! is.na(A)", "! is.na(B)")), ]

identical(D1, D2)

KWB-R/kwb.utils documentation built on April 1, 2024, 7:12 a.m.