tests/testthat/test_conversions.R

In skgrange/threadr: Tools to Thread Pieces Of Data Analysis Together

context("Conversion functions")

test_that("Gas conversions", {
  
  # http://www.apis.ac.uk/unit-conversion
  expect_equal(gas_volume_to_mass(400, gas = "o3"), 856.760, tolerance = 0.001)
  expect_equal(gas_mass_to_volume(800, gas = "o3"), 373.5)
  
  expect_equal(gas_volume_to_mass(3.52734, gas = "nox"), 7.240, tolerance = 0.002)
  
  expect_equal(
    gas_volume_to_mass(3.52734, gas = "nox", temp = 20), 
    3.52734 * 1.912, tolerance = 0.003
  )
  
  expect_equal(gas_mass_to_volume(6.966383, gas = "no2"), 3.394, tolerance = 0.001)
  
  # CO, use the unit switches
  co_mg_m3 <- 0.479359
  
  expect_equal(
    gas_mass_to_volume(
      co_mg_m3, gas = "co", unit_input = "mg_m3", temp = 20, unit_output = "ppm"
    ), 
    ppb_to_ppm(411.618),
    tolerance = 0.0001
  )
  
  expect_equal(
    gas_mass_to_volume(
      co_mg_m3, gas = "co", unit_input = "mg_m3", temp = 20, unit_output = "ppb"
    ), 
    411.618,
    tolerance = 0.0001
  )
  
  # The gas which usually uses different units
  co_ppm <- 7.94 # 7940 ppb
  
  expect_equal(
    gas_volume_to_mass(
      co_ppm, "co", unit_input = "ppm", unit_output = "ug_m3", temp = 20
    ),
    9246.7,
    tolerance = 0.35
  )
  
  expect_equal(
    gas_volume_to_mass(
      co_ppm, "co", unit_input = "ppm", unit_output = "mg_m3", temp = 20
    ), 
    9.2467,
    tolerance = 0.0004
  )
  
  # Could also do this for co:  
  # co_ppb <- ppm_to_ppb(co_ppm)
  # co_ug_m3 <- gas_volume_to_mass(co_ppb, "co", temp = 0)
  # co_mg_m3 <- microgram_to_milligram(co_ug_m3)
  
})


test_that("Easy conversions", {
  
  expect_equal(miles_to_km(3), 1.609344 * 3)
  expect_equal(km_to_miles(6.5), 4.03891, tolerance = 0.00001)
  
  expect_equal(n_mile_to_km(2), 1.852 * 2)
  expect_equal(km_to_n_mile(5), 2.69978, tolerance = 0.00001)
  
})


test_that("Gallon conversions", {
  
  expect_equal(gallon_to_litre(1), 4.54609)
  expect_equal(gallon_to_litre(1, type = "us"), 3.78541, tolerance = 0.00001)
  
  expect_equal(litre_to_gallon(55), 12.0983, tolerance = 0.00001)
  expect_equal(litre_to_gallon(55, type = "us"), 14.529452, tolerance = 0.00001)
  
})


test_that("Fuel consumption conversions", {
  
  # https://www.unitjuggler.com/convert-fuelconsumption-from-lper100km-to-mpg.html
  # mpg
  expect_equal(mpg_to_km_l(38), 13.452235219032)
  expect_equal(mpg_to_km_l(38, type = "us"), 16.15546088464)
  
  expect_equal(mpg_to_l_100_km(40), 7.0620234075)
  expect_equal(mpg_to_l_100_km(40, type = "us"), 5.8803645825)
  
  expect_equal(l_100_km_to_mpg(6), 47.08015605)
  expect_equal(l_100_km_to_mpg(6, type = "us"), 39.20243055)
  
  expect_equal(l_100_km_to_km_l(6), 16.666666666667)
  
})


test_that("temperature conversions", {
  
  expect_equal(fahrenheit_to_celsius(55), 12.777777777778)
  expect_equal(celsius_to_fahrenheit(32.5), 90.5)
  
})


# test_that("Humidity conversions", {
#   
#   # Tested against: https://planetcalc.com/2167/
#   # Approx equal but not precise enough here
#   expect_equal(absolute_humidity(4.9, 84), 0.00569 * 1000)
#   
# })


test_that("Tickier distance transformations ", {

  # Miles per hour to meter per seconds
  # https://www.quora.com/How-do-you-convert-mph-to-meters-per-second
  expect_equal(4.470389, miles_h_to_ms(10), tolerance = 1e-5)
  
  # https://www.formulaconversion.com/formulaconversioncalculator.php?convert=milesperhour_to_meterspersecond
  expect_equal(6.973824, miles_h_to_ms(15.6))
  
  # Miles per hour per second to meter per seconds per second
  # http://www.unit-conversion.info/acceleration.html
  expect_equal(0.4470399999909, miles_h_s_2_to_ms_2(1))
  expect_equal(1.848957439962, miles_h_s_2_to_ms_2(4.136))
  
})