1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
# -*- coding: UTF-8 -*-
# mathlib.py, generic math library wrapper by Reinier Heeres <reinier@heeres.eu>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# Change log:
# 2007-07-03: rwh, first version
import types
import inspect
import math
from decimal import Decimal
from rational import Rational
import random
import logging
_logger = logging.getLogger('MathLib')
from gettext import gettext as _
import locale
class MathLib:
ANGLE_DEG = math.pi/180
ANGLE_RAD = 1
ANGLE_GRAD = 1
FORMAT_EXPONENT = 1
FORMAT_SCIENTIFIC = 2
def __init__(self):
self.set_angle_type(self.ANGLE_DEG)
self.set_format_type(self.FORMAT_SCIENTIFIC)
self.set_digit_limit(9)
self._setup_i18n()
def _setup_i18n(self):
loc = locale.localeconv()
# The separator to mark thousands (default: ',')
self.thousand_sep = loc['thousands_sep']
if self.thousand_sep == "" or self.thousand_sep == None:
self.thousand_sep = ","
# The separator to mark fractions (default: '.')
self.fraction_sep = loc['decimal_point']
if self.fraction_sep == "" or self.fraction_sep == None:
self.fraction_sep = "."
# TRANS: multiplication symbol (default: '*')
self.mul_sym = _('mul_sym')
if len(self.mul_sym) == 0 or len(self.mul_sym) > 3:
self.mul_sym = '*'
# TRANS: division symbol (default: '/')
self.div_sym = _('div_sym')
if len(self.div_sym) == 0 or len(self.div_sym) > 3:
self.div_sym = '/'
def set_angle_type(self, type):
self.angle_scaling = self.d(type)
_logger.debug('Angle type set to %s', self.angle_scaling)
def set_format_type(self, fmt, digit_limit=9):
self.format_type = fmt
_logger.debug('Format type set to %s', fmt)
def set_digit_limit(self, digits):
self.digit_limit = digits
_logger.debug('Digit limit set to %s', digits)
def d(self, val):
if isinstance(val, Decimal):
return val
elif type(val) in (types.IntType, types.LongType):
return Decimal(val)
elif type(val) == types.StringType:
d = Decimal(val)
return d.normalize()
elif type(val) is types.FloatType or hasattr(val, '__float__'):
s = '%.18e' % float(val)
d = Decimal(s)
return d.normalize()
else:
return None
def parse_number(self, s):
s = s.replace(self.fraction_sep, '.')
try:
d = Decimal(s)
if self.is_int(d):
return int(d)
else:
return Decimal(s)
except Exception, inst:
return None
def format_number(self, n):
if type(n) is types.BooleanType:
if n:
return 'True'
else:
return 'False'
elif type(n) is types.StringType:
return n
elif type(n) is types.UnicodeType:
return n
elif type(n) is types.NoneType:
return _('Undefined')
elif type(n) is types.IntType:
n = self.d(n)
elif type(n) is types.FloatType:
n = self.d(n)
elif type(n) is types.LongType:
n = self.d(n)
elif isinstance(n, Rational):
n = self.d(float(n))
elif not isinstance(n, Decimal):
return _('Error: unsupported type')
(sign, digits, exp) = n.as_tuple()
if len(digits) > self.digit_limit:
exp += len(digits) - self.digit_limit
digits = digits[:self.digit_limit]
if sign:
res = "-"
else:
res = ""
int_len = len(digits) + exp
if int_len == 0:
if exp < -self.digit_limit:
disp_exp = exp + len(digits)
else:
disp_exp = 0
elif -self.digit_limit < int_len < self.digit_limit:
disp_exp = 0
else:
disp_exp = int_len - 1
dot_pos = int_len - disp_exp
# _logger.debug('len(digits) %d, exp: %d, int_len: %d, disp_exp: %d, dot_pos: %d', len(digits), exp, int_len, disp_exp, dot_pos)
if dot_pos < 0:
res = '0' + self.fraction_sep
for i in xrange(dot_pos, 0):
res += '0'
for i in xrange(len(digits)):
if i == dot_pos:
if i == 0:
res += '0' + self.fraction_sep
else:
res += self.fraction_sep
res += str(digits[i])
if int_len > 0 and len(digits) < dot_pos:
for i in xrange(len(digits), dot_pos):
res += '0'
if disp_exp != 0:
if self.format_type == self.FORMAT_EXPONENT:
res = res + 'e%d' % disp_exp
elif self.format_type == self.FORMAT_SCIENTIFIC:
res = res + u'×10**%d' % disp_exp
return res
def short_format(self, n):
ret = self.format_number(n)
if len(ret) > 7:
ret = "%1.1e" % n
return ret
def is_int(self, n):
if type(n) is types.IntType or type(n) is types.LongType:
return True
if not isinstance(n, Decimal):
n = self.d(n)
if n is None:
return False
(sign, d, e) = n.normalize().as_tuple()
return e >= 0
if __name__ == "__main__":
ml = MathLib()
val = 0.99999999999999878
print 'is_int(%.18e): %s' % (val, ml.is_int(val))
# Beyond float precision
val = 0.999999999999999999
print 'is_int(%.18e): %s' % (val, ml.is_int(val))
val = ml.d(0.99999999999999878)**2
print 'is_int(%s): %s' % (val, ml.is_int(val))
|
