as.na: Function to accept a vector and return vector of NAs while...

In duanxd1/gfuns: My Global Functions

Description

For use when wishing to maintain attributes of vector while changing values to NA

Usage

as.na(vec)

Arguments

vec	vector of values with class attributes

Examples

# With data.table
library(data.table)

DT <- data.table::data.table(
int = seq(1, 10),
real = seq(1, 10) + 0.1,
char = letters[1:10],
logi = rep(c(TRUE, FALSE), 5),
Date = seq.Date(as.Date("2019-09-03"), by = 1, length.out = 10),
posix = seq.POSIXt(as.POSIXct("2019-09-03 12:00:00"), by = 360, length.out = 10),
factr = as.factor(LETTERS[1:10]))

str(DT)

DT_na <-
  copy(DT)[, lapply(.SD, as.na)]

str(DT_na)

# With data.frame
DF <- data.frame(
  int = seq(1, 10),
  real = seq(1, 10) + 0.1,
  char = letters[1:10],
  logi = rep(c(TRUE, FALSE), 5),
  Date = seq.Date(as.Date("2019-09-03"), by = 1, length.out = 10),
  posix = seq.POSIXt(as.POSIXct("2019-09-03 12:00:00"), by = 360, length.out = 10),
  stringsAsFactors = FALSE
)

DF$factr <- as.factor(LETTERS[1:10])
str(DF)
DF_na <- DF
for(i in colnames(DF)){
  DF_na[,i] <- as.na(DF[,i])
}

str(DF_na)

# Other wasy to do it
# From https://stackoverflow.com/questions/13937345/as-na-function/57779377#57779377
flodel <- function(x) {x[] <- NA; x}
joshU <- function(x) {is.na(x) <- seq_along(x); x}
joshO <- function(x) rep(c(x[0], NA), length(x))

# To benchmark
library(rbenchmark)

# Some vectors to  test them on
int  <- 1:1e6
char <- rep(letters[1:10], 1e5)
bool <- rep(c(TRUE, FALSE), 5e5)

benchmark(replications=100, order="relative",
          flodel_bool = flodel(bool),
          flodel_int  = flodel(int),
          flodel_char = flodel(char),
          joshU_bool = joshU(bool),
          joshU_int  = joshU(int),
          joshU_char = joshU(char),
          joshO_bool = joshO(bool),
          joshO_int  = joshO(int),
          joshO_char = joshO(char),
          as.na_bool = as.na(bool),
          as.na_int = as.na(int),
          as.na_char = as.na(char))[1:6]

benchmark(replications=100, order="relative",
          flodel_DT = DT[, lapply(.SD, flodel)],
          joshU_DT = DT[, lapply(.SD, joshU)],
          joshO_DT = DT[, lapply(.SD, joshO)],
          as.na_DT = DT[, lapply(.SD, as.na)])

benchmark(replications=100, order="relative",
          flodel_DF = {
            DF_na <- DF
            for(i in colnames(DF)){
              DF_na[,i] <- flodel(DF[,i])
            }
            DF_na
          },
          joshU_DF = {
            DF_na <- DF
            for(i in colnames(DF)){
              DF_na[,i] <- joshU(DF[,i])
            }
            DF_na
          },
          joshO_DF = {
            DF_na <- DF
            for(i in colnames(DF)){
              DF_na[,i] <- joshO(DF[,i])
            }
            DF_na
          },
          as.na_DF = {
            DF_na <- DF
            for(i in colnames(DF)){
              DF_na[,i] <- as.na(DF[,i])
            }
            DF_na
          })

duanxd1/gfuns documentation built on March 7, 2020, 12:46 a.m.