o Imporing some old parsing code into a EeVal type. Not quite done yet.

3 files changed, 70 insertions, 2 deletions

diff --git a/src/ee/__init__.py b/src/ee/__init__.py
index b1b825b..bb45ce6 100644
--- a/src/ee/__init__.py
+++ b/src/ee/__init__.py
@@ -1,13 +1,66 @@
 import numpy as np
+import re
+from functools import total_ordering
 
 __all__ = [
-    'EeException',
-    'read_ltspice_raw'
+    "EeException",
+    "EeVal",
+    "read_ltspice_raw"
 ]
 
 class EeException(Exception):
     pass
 
+@total_ordering
+class EeVal(object):
+  from decimal import Decimal
+
+  def __init__(self, s):
+    m = EeVal.r.match(s)
+    if not m:
+      raise EeException("Could not parse value: " + str(s))
+    gs = m.groups()
+    exp = gs[1].strip()
+    self._value = gs[0]
+    self._exp = EeVal.exponents.get(gs[1], 0)
+    self._unit = gs[2]
+
+  @property
+  def value(self):
+    return self._value
+
+  @property
+  def unit(self):
+    return self._exp
+
+  def __eq__(self, other):
+    return ((self._value, self._unit) == (other._value, other._unit))
+
+  def __lt__(self, other):
+    return ((self._value, self._unit) < (other._value, other._unit))
+
+  def __str__(self):
+    return str(self._value) + (" " + str(self._unit) if self._unit else "")
+
+
+EeVal.exponents = {
+    'f': -12,
+    'p': -9,
+    'n': -6,
+    'u': -6,
+    '\u00B5': -6, # The micro symbol
+    'm': -3,
+
+    'k': 3,
+    'M': 6,
+    'G': 9,
+    'T': 12,
+    'P': 15,
+    'E': 18,
+}
+EeVal.units = ['F', 'Ohm', '\u2126', 'H']
+EeVal.r = re.compile("([0-9]+) *([" + "".join(EeVal.exponents.keys()) + "]?)(" + "|".join(EeVal.units) + "?)")
+
 
 class LtSpiceRaw(object):
     def __init__(self, variables, values_first, values_rest):
diff --git a/src/ee/formatting/__init__.py b/src/ee/formatting/__init__.py
index 33673a1..c2b5688 100644
--- a/src/ee/formatting/__init__.py
+++ b/src/ee/formatting/__init__.py
@@ -1,4 +1,5 @@
 import math
+import re
 
 __all__ = [
     'e6', 'e12', 'e24', 'e48', 'e96', 'e192',
diff --git a/test/test_formatting.py b/test/test_formatting.py
index 18f582c..177912d 100644
--- a/test/test_formatting.py
+++ b/test/test_formatting.py
@@ -1,6 +1,7 @@
 import pytest
 import numpy as np
 from ee.formatting import eng_str
+from ee import EeVal
 
 
 @pytest.mark.parametrize("input,expected", [
@@ -60,3 +61,16 @@ def xx_test_eng_str2(input, expected):
 ])
 def xx_test_eng_str3(input, expected):
     assert expected == eng_str(input)
+
+
+@pytest.mark.parametrize("s, expected", [
+    ('1', EeVal("1")),
+    ('10', EeVal("10")),
+    ('10k', EeVal("10e3")),
+    ('10 k', EeVal("10e3")),
+    ('10  k', EeVal("10e3")),
+    ('1p', EeVal("1e-9")),
+    ('100n', EeVal("100e-6")),
+  ])
+def test_EeVal(s, expected):
+    assert expected == EeVal(s)