fcoalesce: Coalescing missing values

Description

Fill in missing values in a vector by successively pulling from candidate vectors in order. As per the ANSI SQL function COALESCE, dplyr::coalesce and hutils::coalesce. Unlike BBmisc::coalesce which just returns the first non-NULL vector. Written in C, and multithreaded for numeric and factor types.

Usage

fcoalesce(..., nan=NA)

Value

Atomic vector of the same type and length as the first vector, having NA values replaced by corresponding non-NA values from the other vectors. If the first item is NULL, the result is NULL.

Arguments

...: A set of same-class vectors. These vectors can be supplied as separate arguments or as a single plain list, data.table or data.frame, see examples.
nan: Either NaN or NA; if NaN, then NaN is treated as distinct from NA, otherwise they are treated the same during replacement (double columns only).

Details

Factor type is supported only when the factor levels of each item are equal.

NaN is considered missing (note is.na(NaN) and all.equal(NA_real_, NaN) are both TRUE).

Examples

Run this code

x = c(11L, NA, 13L, NA, 15L, NA)
y = c(NA, 12L, 5L, NA, NA, NA)
z = c(11L, NA, 1L, 14L, NA, NA)
fcoalesce(x, y, z)
fcoalesce(list(x,y,z))   # same
fcoalesce(x, list(y,z))  # same
x_num = c(NaN, NA_real_, 3.0)
fcoalesce(x_num, 1)           # default: NaN treated as missing -> c(1, 1, 3)
fcoalesce(x_num, 1, nan=NaN)  # preserve NaN -> c(NaN, 1, 3)