1 files changed, 111 insertions, 0 deletions
diff --git a/packages/python/python-soappy-0.11.3/fpconst.py b/packages/python/python-soappy-0.11.3/fpconst.py
index e69de29bb2..3509a139bb 100644
--- a/packages/python/python-soappy-0.11.3/fpconst.py
+++ b/packages/python/python-soappy-0.11.3/fpconst.py
@@ -0,0 +1,111 @@
+"""Utilities for handling IEEE 754 floating point special values
+
+This python module implements constants and functions for working with
+IEEE754 double-precision special values.  It provides constants for
+Not-a-Number (NaN), Positive Infinity (PosInf), and Negative Infinity
+(NegInf), as well as functions to test for these values.
+
+The code is implemented in pure python by taking advantage of the
+'struct' standard module. Care has been taken to generate proper
+results on both big-endian and little-endian machines. Some efficiency
+could be gained by translating the core routines into C.
+
+See <http://babbage.cs.qc.edu/courses/cs341/IEEE-754references.html>
+for reference material on the IEEE 754 floating point standard.
+
+Further information on this package is available at
+<http://software.biostat.washington.edu/statsoft/snake/fpconst>.
+
+Author:    Gregory R. Warnes <gregory_r_warnes@groton.pfizer.com>
+Date::     2003-04-08
+Copyright: (c) 2003, Pfizer, Inc.
+"""
+
+__version__ = "0.6.0"
+ident = "$Id$"
+
+import struct
+
+# check endianess
+_big_endian = struct.pack('i',1)[0] != '\x01'
+
+# and define appropriate constants
+if(_big_endian): 
+    _HW = 0
+    _LW = 1
+    
+    NaN = struct.unpack('d', '\x7F\xFF\xFF\xFF\xFF\xFF\xFF\xFF')[0]
+    PosInf = struct.unpack('d', '\x7F\xF0\x00\x00\x00\x00\x00\x00')[0]
+    NegInf = -PosInf
+    
+else:
+    _HW = 1
+    _LW = 0
+
+    NaN = struct.unpack('d', '\x00\x00\x00\x00\x00\x00\xf8\xff')[0]
+    PosInf = struct.unpack('d', '\x00\x00\x00\x00\x00\x00\xf0\x7f')[0]
+    NegInf = -PosInf
+
+def _double_as_longs(dval):
+    "Use struct.unpack to decode a double precision float into two longs"
+    tmp = struct.unpack('ll',struct.pack('d', dval))
+    return (tmp[_HW], tmp[_LW])
+
+
+##
+## Functions to extract components of the IEEE 754 floating point format
+##
+
+def _sign(dval):
+    "Extract the sign bit from a double-precision floating point value"
+    ll = _double_as_longs(dval)
+    return ll[0] >> 31 & 0x01 
+
+def _exponent(dval):
+    """Extract the exponentent bits from a double-precision floating
+    point value.
+
+    Note that for normalized values, the exponentdent bits have an offset
+    of 1023. As a consequence, the actual exponentent is obtained
+    by subtracting 1023 for the value returned by this function
+    """
+    ll = _double_as_longs(dval)
+    return (ll[0] >> 20) & 0x7ff
+
+def _mantissa(dval):
+    """Extract the _mantissa bits from a double-precision floating
+    point value."""
+
+    ll = _double_as_longs(dval)
+    mantissa0 = (ll[0] & 0x000fffffL) << 32
+    mantissa1 = ll[1] 
+    return mantissa0 + mantissa1
+
+##
+## Functions to test for IEEE 754 special values
+##
+
+def isNaN(value):
+    "Determine if the argument is a IEEE 754 NaN (Not a Number) value."
+    return (_exponent(value)==0x7ff and _mantissa(value)!=0) 
+
+def isInf(value):
+    """Determine if the argument is an infinite IEEE 754 value (positive
+    or negative inifinity)"""
+    return (_exponent(value)==0x7ff and _mantissa(value)== 0)
+
+def isFinite(value):
+    """Determine if the argument is an finite IEEE 754 value (i.e., is
+    not NaN, positive or negative inifinity)"""
+    return (_exponent(value)!=0x7ff)
+
+
+def isPosInf(value):
+    "Determine if the argument is a IEEE 754 positive infinity value"
+    return (_sign(value)==0 and _exponent(value)==0x7ff and \
+            _mantissa(value)== 0) 
+
+def isNegInf(value):
+    "Determine if the argument is a IEEE 754 negative infinity value"
+    return (_sign(value)==1 and _exponent(value)==0x7ff and \
+            _mantissa(value)== 0)