1 files changed, 85 insertions, 0 deletions
diff --git a/src/ee/formatting/__init__.py b/src/ee/formatting/__init__.py
new file mode 100644
index 0000000..3c592ef
--- /dev/null
+++ b/src/ee/formatting/__init__.py
@@ -0,0 +1,85 @@
+#import sympy as sp
+import math
+from ee import EeError
+
+__all__ = [
+    'e6', 'e12', 'e24', 'e48', 'e96', 'e192',
+    'eng_str',
+]
+
+#class Symbols(object):
+#    def __init__(self):
+#        self.tau = sp.symbols('tau'),
+#        self.r = sp.symbols('r'),
+#        self.c = sp.symbols('c')
+#
+#_s = Symbols()
+
+class ESeries(object):
+    def __init__(self, series):
+        self.series = series
+
+    def closest(self, value):
+        e = math.floor(math.log10(value))
+        value = float(value/(10**e))
+
+        return min(self.series, key=lambda v: abs(v - value)) * 10**e
+
+# https://en.wikipedia.org/wiki/E-series_of_preferred_numbers
+_e_series_24 = [1.0, 1.1, 1.2, 1.3, 1.5, 1.6, 1.8, 2.0, 2.2, 2.4, 2.7, 3.0, 3.3, 3.6, 3.9, 4.3, 4.7, 5.1, 5.6, 6.2, 6.8, 7.5, 8.2, 9.1]
+_e_series_12 = [v for i, v in enumerate(_e_series_24) if i % 2 == 0]
+_e_series_6 = [v for i, v in enumerate(_e_series_24) if i % 4 == 0]
+
+_e_series_192 = [
+  1.00, 1.01, 1.02, 1.04, 1.05, 1.06, 1.07, 1.09, 1.10, 1.11,
+  1.13, 1.14, 1.15, 1.17, 1.18, 1.20, 1.21, 1.23, 1.24, 1.26,
+  1.27, 1.29, 1.30, 1.32, 1.33, 1.35, 1.37, 1.38, 1.40, 1.42,
+  1.43, 1.45, 1.47, 1.49, 1.50, 1.52, 1.54, 1.56, 1.58, 1.60,
+  1.62, 1.64, 1.65, 1.67, 1.69, 1.72, 1.74, 1.76, 1.78, 1.80,
+  1.82, 1.84, 1.87, 1.89, 1.91, 1.93, 1.96, 1.98, 2.00, 2.03,
+  2.05, 2.08, 2.10, 2.13, 2.15, 2.18, 2.21, 2.23, 2.26, 2.29,
+  2.32, 2.34, 2.37, 2.40, 2.43, 2.46, 2.49, 2.52, 2.55, 2.58,
+  2.61, 2.64, 2.67, 2.71, 2.74, 2.77, 2.80, 2.84, 2.87, 2.91,
+  2.94, 2.98, 3.01, 3.05, 3.09, 3.12, 3.16, 3.20, 3.24, 3.28,
+  3.32, 3.36, 3.40, 3.44, 3.48, 3.52, 3.57, 3.61, 3.65, 3.70,
+  3.74, 3.79, 3.83, 3.88, 3.92, 3.97, 4.02, 4.07, 4.12, 4.17,
+  4.22, 4.27, 4.32, 4.37, 4.42, 4.48, 4.53, 4.59, 4.64, 4.70,
+  4.75, 4.81, 4.87, 4.93, 4.99, 5.05, 5.11, 5.17, 5.23, 5.30,
+  5.36, 5.42, 5.49, 5.56, 5.62, 5.69, 5.76, 5.83, 5.90, 5.97,
+  6.04, 6.12, 6.19, 6.26, 6.34, 6.42, 6.49, 6.57, 6.65, 6.73,
+  6.81, 6.90, 6.98, 7.06, 7.15, 7.23, 7.32, 7.41, 7.50, 7.59,
+  7.68, 7.77, 7.87, 7.96, 8.06, 8.16, 8.25, 8.35, 8.45, 8.56,
+  8.66, 8.76, 8.87, 8.98, 9.09, 9.20, 9.31, 9.42, 9.53, 9.65,
+  9.76, 9.88,
+]
+_e_series_96 = [v for i, v in enumerate(_e_series_192) if i % 2 == 0]
+_e_series_48 = [v for i, v in enumerate(_e_series_192) if i % 4 == 0]
+
+e6 = ESeries(_e_series_6)
+e12 = ESeries(_e_series_12)
+e24 = ESeries(_e_series_24)
+e48 = ESeries(_e_series_48)
+e96 = ESeries(_e_series_96)
+e192 = ESeries(_e_series_192)
+
+def e_series_find_closest(value):
+    e = math.floor(math.log10(value))
+    value = float(value/(10**e))
+
+    return min(series, key=lambda v: abs(v - value)) * 10**e
+
+def eng_str(value):
+    big = ['', ' k', ' M', ' G', ' T']
+    e_floor = math.floor(math.log10(value))
+
+    div3 = int(math.floor(e_floor/3))
+    suffix = big[div3]
+    scale = 10**(div3*3)
+    scaled = value/scale
+
+    if scaled == int(scaled):
+        return "{:1.0f}{}".format(scaled, suffix)
+    else:
+        return "{:1.1f}{}".format(scaled, suffix)
+
+#    return "scaled={:>9}, div3={}, floor(e)={}, scale={}, suffix={}".format(str(scaled), div3, e_floor, scale, suffix)