install_conversion_constant: Install a conversion constant or offset between user-defined...

Description Usage Arguments Details See Also Examples

View source: R/user_conversion.R

Description

Tells the units package how to convert between units that have a linear relationship, i.e. can be related on the form y = α x (constant) or y = α + x (offset).

Usage

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install_conversion_constant(from, to, const)

install_conversion_offset(from, to, const)

Arguments

from

String for the symbol of the unit being converted from.

to

String for the symbol of the unit being converted to. One of from and to must be an existing unit name.

const

The constant α in the conversion.

Details

This function handles the very common case where units are related through a linear function, that is, you can convert from one to the other as y = α x. Using this function, you specify that you can go from values of type from to values of type to by multiplying by a constant, or adding a constant.

See Also

install_symbolic_unit, remove_symbolic_unit

Examples

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# one orange is worth two apples
install_symbolic_unit("orange")
install_conversion_constant("orange", "apple", 2) # apple = 2 * orange
apples <- 2 * as_units("apple")
oranges <- 1 * as_units("orange")
apples + oranges
oranges + apples

install_conversion_offset("meter", "newmeter", 1)
m = set_units(1:3, meter)
n = set_units(1:3, newmeter)
m + n
n + m

r-quantities/units documentation built on March 31, 2020, 12:08 p.m.