SF.net SVN: fclient: [218] trunk/sandbox/fcp/fcp_lib/numbers.py

[<ju...@us...>]

Revision: 218
          http://fclient.svn.sourceforge.net/fclient/?rev=218&view=rev
Author:   jurner
Date:     2008-02-16 02:09:58 -0800 (Sat, 16 Feb 2008)

Log Message:
-----------
comb over

Modified Paths:
--------------
    trunk/sandbox/fcp/fcp_lib/numbers.py

Modified: trunk/sandbox/fcp/fcp_lib/numbers.py
===================================================================
--- trunk/sandbox/fcp/fcp_lib/numbers.py	2008-02-16 10:09:26 UTC (rev 217)
+++ trunk/sandbox/fcp/fcp_lib/numbers.py	2008-02-16 10:09:58 UTC (rev 218)
@@ -6,11 +6,19 @@
 #***************************************************************
 #
 #***************************************************************
-def format_num_bytes(num, short=True, conform=True):
+class ByteSizeNames:
+	Binary = ('B', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB')
+	Common = ('B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB')
+	
+	
+
+def format_num_bytes(num, binary=False, names=None, format_strings=('%i%s', '%01.2f%s') ):
 	"""Formats a number representing a number of bytes to a human readable string
 	@param num: (int) number to fomat
-	@param short: use short names
-	@param conform: if True factor is 1000, else factor is 1024
+	@param binary: if True conversion factor is 1024, else factor is 1000
+	@param names: (tuple) names to use as suffix  or None to use default names (see L{ByteSizeNames})
+	@param format_strings: (tuple) format strings to be used or None to use the default formating.
+	The first member of the tuple is used to format bytes, the seconds anything > one kilobyte
 	@return: (str) formated number
 	
 	>>> format_num_bytes(100)
@@ -19,43 +27,24 @@
 	>>> format_num_bytes(1000)
 	'1.00KB'
 	
-	>>> format_num_bytes(1024, conform=False)
+	>>> format_num_bytes(1024, binary=True)
 	'1.00KiB'
 	
-	>>> format_num_bytes(1000, short=False)
-	'1.00Kilobyte'
+	>>> format_num_bytes(1000, names=('W', 'X', 'Y', 'Z'))
+	'1.00X'
 		
+	>>> format_num_bytes(1000, format_strings=('%s%i', '%01.4f%s'))
+	'1.0000KB'
+	
 	"""
-	if conform:
+	if binary:
+		factor = 1024
+		if names is None:
+			names = ByteSizeNames.Binary
+	else:
 		factor = 1000
-		if short:
-			names = ('B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB')
-		else:
-			names = ('Byte', 
-							'Kilobyte', 
-							'Megabyte', 
-							'Gigabyte', 
-							'Terabyte', 
-							'Petabyte', 
-							'Exabyte', 
-							'Zettabyte', 
-							'Yottabyte'
-							)
-	else:
-		factor = 1024
-		if short:
-			names = ('B', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB')
-		else:
-			names = ('Byte', 
-							'Kibibyte', 
-							'Mebibyte', 
-							'Gibibyte', 
-							'Tebibyte', 
-							'Pebibyte', 
-							'Exibyte', 
-							'Zebibyte', 
-							'Yobiabyte'
-							)
+		if names is None:
+			names = ByteSizeNames.Common
 		
 	name = names[0]
 	if num >= factor:
@@ -66,11 +55,78 @@
 			if num < factor:
 				break
 	else:
-		return '%i%s' % (num, name)
+		return format_strings[0] % (num, name)
+	return format_strings[1] % (num, name)
+
+
+NumBytesPat = re.compile('''\A   (\d+ \. \d+)  |  (\d+)''', re.X)
+def num_bytes_to_bytes(num, binary=False, names=None):
+	"""Converts a string containing a bytes size to an integer
+	@param num: (str) string to convert
+	@param binary: if True conversion factor is 1024, else factor is 1000
+	@param names: (tuple) names to use as suffix  or None to use default names (see L{ByteSizeNames})
+	
+	@return: (int) number of bytes
+	@note: postfixes are handled case sensitive
+	
+	>>> num_bytes_to_bytes('1000B')
+	1000
+	
+	>>> num_bytes_to_bytes('1GB')
+	1000000000
+	
+	>>> num_bytes_to_bytes('1.2KB')
+	1200
+	
+	>>> num_bytes_to_bytes('1.5678B')
+	2
+	
+	>>> num_bytes_to_bytes('1MiB', binary=True)
+	1048576
+	
+	>>> num_bytes_to_bytes('1X', names=('X', ))
+	1
 		
-	return '%01.2f%s' % (num, name)
+	>>> num_bytes_to_bytes('foo')
+	Traceback (most recent call last):
+		...
+	ValueError: No number found in input string
+		
+	>>> num_bytes_to_bytes('1foo')
+	Traceback (most recent call last):
+		...
+	ValueError: Unknown size postfix
+	"""
+	if names is None:
+		if binary:
+			names = ByteSizeNames.Binary
+		else:
+			names = ByteSizeNames.Common
+	names = list(names)
+		
+	match = NumBytesPat.match(num)
+	if match is None:
+		raise ValueError('No number found in input string')
+	
+	isfloat, isint = match.groups()
+	if isfloat:
+		z = len(isfloat)
+		tmp_num = float(isfloat)
+	else:
+		z = len(isint)
+		tmp_num = int(isint)
+		
+	postfix = num[z: ]
+	try:
+		exp = names.index(postfix)
+	except ValueError:
+		raise ValueError('Unknown size postfix')
+	factor = 1024 if binary else 1000	
+		
+	#TODO: 1.96B is returned rounded as 2. Should we complain?
+	return int(round(tmp_num * (factor ** exp)))
+		
 
-
 #***************************************************************
 #
 #***************************************************************
@@ -245,6 +301,7 @@
 		num = pat.sub('', num)
 	return num
 
+
 #*****************************************************************
 #
 #****************************************************************


This was sent by the SourceForge.net collaborative development platform, the world's largest Open Source development site.