substances: Substance-Aware Unit Conversions in R

Overview

The substances package enables substance-aware unit conversions in R. It facilitates transformations between mass and molar units, supports nonstandard medical unit conversions, and extends the functionality of the units package by incorporating molecular weight calculations and domain-specific unit conversions.

Installation

To install the development version from GitHub, use:

# Install devtools if not already installed
install.packages("devtools")

# Install substances package
devtools::install_github("geeky33/substances", build_vignettes = TRUE)

Features

• Define substances with molecular weight and unit properties.
• Convert between mass and moles for a given substance.
• Perform conversions between nonstandard medical units.
• Support arithmetic operations on substances.

Usage

Load the Package

library(substances)

Creating Substances

# Define a new substance
water <- new("substances", name = "water", molecular_weight = 18.02, unit = "g/mol")

Mass-to-Molar Conversions

# Convert 36.04 grams of water to moles
mass_to_moles(36.04, water)  # Output: 2 moles

# Convert 2 moles of water to mass
moles_to_mass(2, water)  # Output: 36.04 grams

Medical Unit Conversions

# Convert 50 U/L to ukat/L
convert_medical_units(50, "U/L", "ukat/L")  # Output: 5e-5 ukat/L

Arithmetic Operations on Substances

ethanol <- new("substances", name = "ethanol", molecular_weight = 46.07, unit = "g/mol")

# Adding two identical substances
combined_ethanol <- ethanol + ethanol
combined_ethanol@molecular_weight  # Output: 92.14 g/mol

# Scaling a substance
scaled_ethanol <- ethanol * 2
scaled_ethanol@molecular_weight  # Output: 92.14 g/mol

License

This package is licensed under the MIT License.