subsetting: Subsetting objects created using swfscAirDAS

In swfscAirDAS: Southwest Fisheries Science Center Aerial DAS Data Processing

Subsetting objects created using swfscAirDAS

Description

Subsetting airdas_dfr or airdas_df objects

Usage

## S3 method for class 'airdas_dfr'
x[i, j, ..., drop = TRUE]

## S3 replacement method for class 'airdas_dfr'
x$name <- value

## S3 replacement method for class 'airdas_dfr'
x[i, j, ...] <- value

## S3 replacement method for class 'airdas_dfr'
x[[i]] <- value

## S3 method for class 'airdas_df'
x[i, j, ..., drop = TRUE]

## S3 replacement method for class 'airdas_df'
x$name <- value

## S3 replacement method for class 'airdas_df'
x[i, j, ...] <- value

## S3 replacement method for class 'airdas_df'
x[[i]] <- value

Arguments

x	object of class airdas_dfr or airdas_df
i, j, ...	elements to extract or replace, see [.data.frame
drop	logical, see [.data.frame
name	A literal character string or ..., see [.data.frame
value	A suitable replacement value, see [.data.frame

Details

When subsetting a airdas_dfr or airdas_df object, henceforth a airdas_ object, using any of the functions described in [.data.frame, then then the airdas_ class is simply dropped and the object is of class data.frame. This is because of the strict format requirements of airdas_ objects; it is likely that a subsetted airdas_ object will not have the format required by subsequent swfscAirDAS functions, and thus it is safest to drop the airdas_ class. If a data frame is passed to downstream swfscAirDAS functions that require a airdas_ object, then they will attempt to coerce the object to the necessary airdas_ class See as_airdas_dfr and as_airdas_df for more details.

Examples

y <- system.file("airdas_sample.das", package = "swfscAirDAS")
y.read <- airdas_read(y)

# All return a data frame:
class(y.read[1:10, ])
class(y.read[, 1:10])

y.df <- y.read
y.df[, 1] <- "a"
class(y.df)

y.df <- y.read
y.df$Event <- "a"
class(y.df)

y.df <- y.read
y.df[["Event"]] <- "a"
class(y.df)

swfscAirDAS documentation built on Aug. 9, 2023, 1:06 a.m.