1 files changed, 48 insertions, 0 deletions
diff --git a/glucometerutils/common.py b/glucometerutils/common.py
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+++ b/glucometerutils/common.py
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+"""Common routines for data in glucometers."""
+
+__author__ = 'Diego Elio Pettenò'
+__email__ = 'flameeyes@flameeyes.eu'
+__copyright__ = 'Copyright © 2013, Diego Elio Pettenò'
+__license__ = 'GPL v3 or later'
+
+# Constants for units
+UNIT_MGDL = 'mg/dL'
+UNIT_MMOLL = 'mmol/L'
+
+VALID_UNITS = [UNIT_MGDL, UNIT_MMOLL]
+
+# Constants for date format
+DATETIME_12HR = '12 hours'
+DATETIME_24HR = '24 hours'
+
+from glucometerutils import exceptions
+
+
+def ConvertGlucoseUnit(value, from_unit, to_unit=None):
+  """Convert the given value of glucose level between units.
+
+  Args:
+    value: The value of glucose in the current unit
+    from_unit: The unit value is currently expressed in
+    to_unit: The unit to conver the value to: the other if empty.
+
+  Returns:
+    The converted representation of the blood glucose level.
+
+  Raises:
+    exceptions.InvalidGlucoseUnit: If the parameters are incorrect.
+  """
+  if from_unit not in VALID_UNITS:
+    raise exceptions.InvalidGlucoseUnit(from_unit)
+
+  if from_unit == to_unit:
+    return value
+
+  if to_unit is not None:
+    if to_unit not in VALID_UNITS:
+      raise exceptions.InvalidGlucoseUnit(to_unit)
+
+  if from_unit is UNIT_MGDL:
+    return round(value / 18.0, 2)
+  else:
+    return round(value * 18.0, 0)