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quantities (version 0.2.2)

parse_quantities: Parse Units and Errors

Description

Functions to parse character vectors into quantities.

Usage

parse_quantities(x, decimal_mark)

parse_units(x, decimal_mark)

parse_errors(x, decimal_mark)

Value

A quantities, units or errors object respectively.

Arguments

x

a character vector to parse.

decimal_mark

the dot (.) if not provided.

Details

Each parse_*() function returns an object of the corresponding type, no matter what it is found. This means that, for parse_units, if errors are found, they are dropped with a warning. Similarly for parse_errors, if units are found, they are dropped with a warning. On the other hand, parse_quantities always returns a valid quantities object, even if no errors or units are found (then, zero error and dimensionless units are applied).

Examples

Run this code
parse_quantities("(1.6021766208 +/- .0000000098) e-19 C")
parse_quantities("1.6021766208(98) e-19 C")
parse_units("1.6021766208 e-19 C")
parse_errors("1.6021766208(98) e-19")

# quantities are converted to the first unit
parse_quantities(c("12.34(2) m/s", "36.5(1) km/h"))

# or kept as a list of mixed units
parse_quantities(c("1.02(5) g", "2.51(0.01) V", "(3.23 +/- 0.12) m"))

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