conversion_utils.py

   1 #!/usr/bin/env python3
   2
   3 from numbers import Number
   4 from typing import Callable
   5
   6 import constants
   7
   8
   9 class Converter(object):
  10     def __init__(self,
  11                  name: str,
  12                  category: str,
  13                  to_canonical: Callable,
  14                  from_canonical: Callable,
  15                  unit: str) -> None:
  16         self.name = name
  17         self.category = category
  18         self.to_canonical_f = to_canonical
  19         self.from_canonical_f = from_canonical
  20         self.unit = unit
  21
  22     def to_canonical(self, n: Number) -> Number:
  23         return self.to_canonical_f(n)
  24
  25     def from_canonical(self, n: Number) -> Number:
  26         return self.from_canonical_f(n)
  27
  28     def unit_suffix(self) -> str:
  29         return self.unit
  30
  31
  32 conversion_catalog = {
  33     "Second": Converter("Second",
  34                         "time",
  35                         lambda s: s,
  36                         lambda s: s,
  37                         "s"),
  38     "Minute": Converter("Minute",
  39                         "time",
  40                         lambda m: (m * constants.SECONDS_PER_MINUTE),
  41                         lambda s: (s / constants.SECONDS_PER_MINUTE),
  42                         "m"),
  43     "Hour": Converter("Hour",
  44                       "time",
  45                       lambda h: (h * constants.SECONDS_PER_HOUR),
  46                       lambda s: (s / constants.SECONDS_PER_HOUR),
  47                       "h"),
  48     "Day": Converter("Day",
  49                      "time",
  50                      lambda d: (d * constants.SECONDS_PER_DAY),
  51                      lambda s: (s / constants.SECONDS_PER_DAY),
  52                      "d"),
  53     "Week": Converter("Week",
  54                       "time",
  55                       lambda w: (w * constants.SECONDS_PER_WEEK),
  56                       lambda s: (s / constants.SECONDS_PER_WEEK),
  57                       "w"),
  58     "Fahrenheit": Converter("Fahrenheit",
  59                             "temperature",
  60                             lambda f: (f - 32.0) * 0.55555555,
  61                             lambda c: c * 1.8 + 32.0,
  62                             "°F"),
  63     "Celsius": Converter("Celsius",
  64                          "temperature",
  65                          lambda c: c,
  66                          lambda c: c,
  67                          "°C"),
  68     "Kelvin": Converter("Kelvin",
  69                         "temperature",
  70                         lambda k: k - 273.15,
  71                         lambda c: c + 273.15,
  72                         "°K"),
  73 }
  74
  75
  76 def convert(magnitude: Number,
  77             from_thing: str,
  78             to_thing: str) -> float:
  79     src = conversion_catalog.get(from_thing, None)
  80     dst = conversion_catalog.get(to_thing, None)
  81     if src is None or dst is None:
  82         raise ValueError("No known conversion")
  83     if src.category != dst.category:
  84         raise ValueError("Incompatible conversion")
  85     return _convert(magnitude, src, dst)
  86
  87
  88 def _convert(magnitude: Number,
  89              from_unit: Converter,
  90              to_unit: Converter) -> float:
  91     canonical = from_unit.to_canonical(magnitude)
  92     converted = to_unit.from_canonical(canonical)
  93     return float(converted)
  94
  95
  96 def sec_to_min(s: float) -> float:
  97     return convert(s, "Second", "Minute")
  98
  99
 100 def sec_to_hour(s: float) -> float:
 101     return convert(s, "Second", "Hour")
 102
 103
 104 def sec_to_day(s: float) -> float:
 105     return convert(s, "Second", "Day")
 106
 107
 108 def sec_to_week(s: float) -> float:
 109     return convert(s, "Second", "Week")
 110
 111
 112 def min_to_sec(m: float) -> float:
 113     return convert(m, "Minute", "Second")
 114
 115
 116 def min_to_hour(m: float) -> float:
 117     return convert(m, "Minute", "Hour")
 118
 119
 120 def min_to_day(m: float) -> float:
 121     return convert(m, "Minute", "Day")
 122
 123
 124 def min_to_week(m: float) -> float:
 125     return convert(m, "Minute", "Week")
 126
 127
 128 def hour_to_sec(h: float) -> float:
 129     return convert(h, "Hour", "Second")
 130
 131
 132 def hour_to_min(h: float) -> float:
 133     return convert(h, "Hour", "Minute")
 134
 135
 136 def hour_to_day(h: float) -> float:
 137     return convert(h, "Hour", "Day")
 138
 139
 140 def hour_to_week(h: float) -> float:
 141     return convert(h, "Hour", "Week")
 142
 143
 144 def day_to_sec(d: float) -> float:
 145     return convert(d, "Day", "Second")
 146
 147
 148 def day_to_min(d: float) -> float:
 149     return convert(d, "Day", "Minute")
 150
 151
 152 def day_to_hour(d: float) -> float:
 153     return convert(d, "Day", "Hour")
 154
 155
 156 def day_to_week(d: float) -> float:
 157     return convert(d, "Day", "Week")
 158
 159
 160 def week_to_sec(w: float) -> float:
 161     return convert(w, "Week", "Second")
 162
 163
 164 def week_to_min(w: float) -> float:
 165     return convert(w, "Week", "Minute")
 166
 167
 168 def week_to_hour(w: float) -> float:
 169     return convert(w, "Week", "Hour")
 170
 171
 172 def week_to_day(w: float) -> float:
 173     return convert(w, "Week", "Day")
 174
 175
 176 def f_to_c(temp_f: float) -> float:
 177     """Fahrenheit to Celsius."""
 178     return convert(temp_f, "Fahrenheit", "Celsius")
 179
 180
 181 def c_to_f(temp_c: float) -> float:
 182     """Celsius to Fahrenheit."""
 183     return convert(temp_c, "Celsius", "Fahrenheit")