add over.core.m

add over.core.m.compare_float

core/__init__.py

@@ -1,6 +1,7 @@
 #! /usr/bin/env python3
 # encoding: utf-8
 
+from . import m
 from . import app
 from . import aux
 from . import cmd

core/m.py

@@ -0,0 +1,46 @@
+#! /usr/bin/env python3
+# encoding: utf-8
+
+import sys
+
+class compare_float:
+	"""
+	Sets .lt, .eq or .gt iff A is less than, equal (within epsilon) or greather than B.
+	"""
+	
+	def __init__(self, A, B, epsilon=sys.float_info.epsilon):
+		self.lt = False
+		self.le = True
+		self.eq = False
+		self.ge = True
+		self.gt = False
+		
+		if A < B:
+			self.lt = True
+			self.le = True
+			self.ge = False
+		elif A > B:
+			self.gt = True
+			self.le = False
+			self.ge = True
+		
+		if abs(A - B) < epsilon:
+			self.eq = True
+		else:
+			self.le = False
+			self.ge = False
+		
+		# convenience
+		self.less = self.lt
+		self.less_or_equal = self.le
+		self.equal = self.eq
+		self.greater_or_equal = self.ge
+		self.greater = self.gt
+
+if __name__ == '__main__':
+	x = compare_float(1, 2, 0.5)
+	assert x.lt and x.less and not (x.le or x.ge)
+	x = compare_float(2, 2, 0.5)
+	assert x.eq and x.le and x.ge and not (x.lt or x.gt)
+	x = compare_float(3, 2, 0.5)
+	assert x.gt and not (x.ge or x.eq or x.lt)