# Functions for dealing with dates and times.
import re
import string
def timestringtoseconds(text, separator = ':'):
inputList = string.split(string.strip(text), separator)
if len(inputList) != 3:
raise ValueError, 'invalid value: ' + text
sign = 1
if len(inputList[0]) > 0 and inputList[0][0] in ('+', '-'):
if inputList[0][0] == '-':
sign = -1
inputList[0] = inputList[0][1:]
if re.search('[^0-9]', string.join(inputList, '')) is not None:
raise ValueError, 'invalid value: ' + text
hour = string.atoi(inputList[0])
minute = string.atoi(inputList[1])
second = string.atoi(inputList[2])
if minute >= 60 or second >= 60:
raise ValueError, 'invalid value: ' + text
return sign * (hour * 60 * 60 + minute * 60 + second)
_year_pivot = 50
_century = 2000
def setyearpivot(pivot, century = None):
global _year_pivot
global _century
oldvalues = (_year_pivot, _century)
_year_pivot = pivot
if century is not None:
_century = century
return oldvalues
def datestringtojdn(text, format = 'ymd', separator = '/'):
inputList = string.split(string.strip(text), separator)
if len(inputList) != 3:
raise ValueError, 'invalid value: ' + text
if re.search('[^0-9]', string.join(inputList, '')) is not None:
raise ValueError, 'invalid value: ' + text
formatList = list(format)
day = string.atoi(inputList[formatList.index('d')])
month = string.atoi(inputList[formatList.index('m')])
year = string.atoi(inputList[formatList.index('y')])
if _year_pivot is not None:
if year >= 0 and year < 100:
if year <= _year_pivot:
year = year + _century
else:
year = year + _century - 100
jdn = ymdtojdn(year, month, day)
if jdntoymd(jdn) != (year, month, day):
raise ValueError, 'invalid value: ' + text
return jdn
def _cdiv(a, b):
# Return a / b as calculated by most C language implementations,
# assuming both a and b are integers.
if a * b > 0:
return a / b
else:
return -(abs(a) / abs(b))
def ymdtojdn(year, month, day, julian = -1, papal = 1):
# set Julian flag if auto set
if julian < 0:
if papal: # Pope Gregory XIII's decree
lastJulianDate = 15821004L # last day to use Julian calendar
else: # British-American usage
lastJulianDate = 17520902L # last day to use Julian calendar
julian = ((year * 100L) + month) * 100 + day <= lastJulianDate
if year < 0:
# Adjust BC year
year = year + 1
if julian:
return 367L * year - _cdiv(7 * (year + 5001L + _cdiv((month - 9), 7)), 4) + \
_cdiv(275 * month, 9) + day + 1729777L
else:
return (day - 32076L) + \
_cdiv(1461L * (year + 4800L + _cdiv((month - 14), 12)), 4) + \
_cdiv(367 * (month - 2 - _cdiv((month - 14), 12) * 12), 12) - \
_cdiv((3 * _cdiv((year + 4900L + _cdiv((month - 14), 12)), 100)), 4) + \
1 # correction by rdg
def jdntoymd(jdn, julian = -1, papal = 1):
# set Julian flag if auto set
if julian < 0:
if papal: # Pope Gregory XIII's decree
lastJulianJdn = 2299160L # last jdn to use Julian calendar
else: # British-American usage
lastJulianJdn = 2361221L # last jdn to use Julian calendar
julian = (jdn <= lastJulianJdn);
x = jdn + 68569L
if julian:
x = x + 38
daysPer400Years = 146100L
fudgedDaysPer4000Years = 1461000L + 1
else:
daysPer400Years = 146097L
fudgedDaysPer4000Years = 1460970L + 31
z = _cdiv(4 * x, daysPer400Years)
x = x - _cdiv((daysPer400Years * z + 3), 4)
y = _cdiv(4000 * (x + 1), fudgedDaysPer4000Years)
x = x - _cdiv(1461 * y, 4) + 31
m = _cdiv(80 * x, 2447)
d = x - _cdiv(2447 * m, 80)
x = _cdiv(m, 11)
m = m + 2 - 12 * x
y = 100 * (z - 49) + y + x
# Convert from longs to integers.
yy = int(y)
mm = int(m)
dd = int(d)
if yy <= 0:
# Adjust BC years.
yy = yy - 1
return (yy, mm, dd)
def stringtoreal(text, separator = '.'):
if separator != '.':
if string.find(text, '.') >= 0:
raise ValueError, 'invalid value: ' + text
index = string.find(text, separator)
if index >= 0:
text = text[:index] + '.' + text[index + 1:]
return string.atof(text)
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