Convert a vector to decimal

as_decimal() is the conversion generic for decimal vectors. Character values are parsed exactly, integer values are converted exactly, and existing decimal vectors are returned or rescaled. Promotion to a finer shared scale is exact and context-free; reduction to a coarser scale is quantized. Double values are decoded from their exact IEEE 754 representation and therefore require an explicit or globally configured scale before quantization.

Usage

# S3 method for class 'Array'
as_decimal(x, scale = NULL)

# S3 method for class 'ChunkedArray'
as_decimal(x, scale = NULL)

as_decimal(x, scale = NULL)

# S3 method for class 'decimal'
as_decimal(x, scale = NULL)

# S3 method for class 'character'
as_decimal(x, scale = NULL)

# S3 method for class 'integer'
as_decimal(x, scale = NULL)

# S3 method for class 'numeric'
as_decimal(x, scale = NULL)

# Default S3 method
as_decimal(x, scale = NULL)

Arguments

x

A decimal, character, integer, or double vector, or an Arrow Array or ChunkedArray.

scale

An integer scalar giving the number of fractional digits to store, or NULL to use the global default or input-specific inference.

Value

A decimal vector.

Details

When scale is NULL, getOption("decimal.default_scale") is used when set. Without that option, character input uses the largest number of fractional digits found in the input, integer input uses scale zero, and double input raises an error. Quantization uses the active decimal_context().

An Arrow Array or ChunkedArray of any decimal type converts exactly, taking its scale from the Arrow type rather than from the values, so a chunk holding only whole numbers keeps its declared fractional digits. An Arrow integer array converts exactly at every width. Any other Arrow type converts to an R vector first and then follows the rules above. See decimal_arrow and vignette("arrow-decimal-types").

Examples

as_decimal(c("1.2", "3.45"))
#> <decimal[2]>
#> [1] 1.20 3.45