我们从Python开源项目中，提取了以下35个代码示例，用于说明如何使用decimal.ROUND_FLOOR。
def _converter_date(value): m = iso8601.match(value) year = int(m.group("year")) month = int(m.group("month") or "1") day = int(m.group("day") or "1") hour = int(m.group("hour") or "0") minute = int(m.group("minute") or "0") second = decimal.Decimal(m.group("second") or "0") seconds = second.to_integral(decimal.ROUND_FLOOR) milliseconds = (second - seconds) * 1000000 tzd = m.group("tzd") or "Z" dt = datetime.datetime(year, month, day, hour, minute, seconds, milliseconds) if tzd != "Z": tzd_hours, tzd_minutes = [int(x) for x in tzd.split(":")] tzd_hours *= -1 if tzd_hours < 0: tzd_minutes *= -1 dt = dt + datetime.timedelta(hours=tzd_hours, minutes=tzd_minutes) return dt
def __init__(self, min_value=None, max_value=None, force_string=False, precision=2, rounding=decimal.ROUND_HALF_UP, **kwargs): """ :param min_value: Validation rule for the minimum acceptable value. :param max_value: Validation rule for the maximum acceptable value. :param force_string: Store as a string. :param precision: Number of decimal places to store. :param rounding: The rounding rule from the python decimal library: - decimal.ROUND_CEILING (towards Infinity) - decimal.ROUND_DOWN (towards zero) - decimal.ROUND_FLOOR (towards -Infinity) - decimal.ROUND_HALF_DOWN (to nearest with ties going towards zero) - decimal.ROUND_HALF_EVEN (to nearest with ties going to nearest even integer) - decimal.ROUND_HALF_UP (to nearest with ties going away from zero) - decimal.ROUND_UP (away from zero) - decimal.ROUND_05UP (away from zero if last digit after rounding towards zero would have been 0 or 5; otherwise towards zero) Defaults to: ``decimal.ROUND_HALF_UP`` """ self.min_value = min_value self.max_value = max_value self.force_string = force_string self.precision = precision self.rounding = rounding super(DecimalField, self).__init__(**kwargs)
def round_decimal(value, prec): if isinstance(value, float): return round(value, prec) # can also use shift() here but that is 2.6 only return (value * decimal.Decimal("1" + "0" * prec) ).to_integral(decimal.ROUND_FLOOR) / \ pow(10, prec)
def calculate_mpg(self): """ Calculate ``calculated_mpg`` field. :returns: True if recalculate, False if unable to calculate :rtype: bool """ if self.gallons is None: logger.warning( 'Gallons is none; cannot recalculate MPG for %s', self ) return False if self.odometer_miles is None: logger.warning( 'odometer_miles is none; cannot recalculate MPG for %s', self ) return False prev = self._previous_entry() if prev is None: logger.warning('Previous entry is None; cannot recalculate MPG ' 'for %s', self) return False distance = self.odometer_miles - prev.odometer_miles self.calculated_miles = distance self.calculated_mpg = ( (distance * Decimal(1.0)) / self.gallons ).quantize(Decimal('.001'), rounding=ROUND_FLOOR) logger.debug('Calculate MPG for fill %d: distance=%s mpg=%s', self.id, distance, self.calculated_mpg) inspect(self).session.add(self)
def calculate_wind_chill(temperature, wind_speed): """ Uses the air temperature and wind speed to calculate the wind chill, the purpose of which is to represent a "felt-air temperature" close to what a human actually feels given the temperature and wind speed. This index does not take into account the humidity or solar radiation, and so is not the most accurate measure of a true "feels-like" temperature. For that, see `calculate_thw_index` and `calculate_thsw_index`. The algorithm used and its constants are sourced from the chart at http://www.srh.noaa.gov/ssd/html/windchil.htm, and the function is tested against the same chart. In this algorithm: T is the temperature in degrees Fahrenheit WS is the wind speed in miles per hour This function returns `None` if the input temperature is above 40F. :param temperature: The temperature in degrees Fahrenheit :type temperature: int | long | decimal.Decimal :param wind_speed: The wind speed in miles per hour :type wind_speed: int | long | decimal.Decimal :return: The wind chill temperature in degrees Fahrenheit to one decimal place, or `None` if the temperature is higher than 40F :rtype: decimal.Decimal """ if temperature > WIND_CHILL_THRESHOLD: return None T = temperature WS = _as_decimal(wind_speed) if WS == ZERO: # No wind results in no chill, so skip it return T V = WS ** WC_V_EXP wind_chill = ( WC_C1 + (WC_C2 * T) - (WC_C3 * V) + (WC_C4 * T * V) ).quantize(ONE_TENTH, rounding=decimal.ROUND_FLOOR) return T if wind_chill > T else wind_chill # noinspection PyPep8Naming
def stepBy(self, n): n = D(int(n)) ## n must be integral number of steps. s = [D(-1), D(1)][n >= 0] ## determine sign of step val = self.val for i in range(int(abs(n))): if self.opts['log']: raise Exception("Log mode no longer supported.") # step = abs(val) * self.opts['step'] # if 'minStep' in self.opts: # step = max(step, self.opts['minStep']) # val += step * s if self.opts['dec']: if val == 0: step = self.opts['minStep'] exp = None else: vs = [D(-1), D(1)][val >= 0] #exp = D(int(abs(val*(D('1.01')**(s*vs))).log10())) fudge = D('1.01')**(s*vs) ## fudge factor. at some places, the step size depends on the step sign. exp = abs(val * fudge).log10().quantize(1, rounding=ROUND_FLOOR) step = self.opts['step'] * D(10)**exp if 'minStep' in self.opts: step = max(step, self.opts['minStep']) val += s * step #print "Exp:", exp, "step", step, "val", val else: val += s*self.opts['step'] if 'minStep' in self.opts and abs(val) < self.opts['minStep']: val = D(0) self.setValue(val, delaySignal=True) ## note all steps (arrow buttons, wheel, up/down keys..) emit delayed signals only.
def fquotmod(val, low, high): ''' A divmod function with boundaries. ''' # assumes that all the maths is done with Decimals. # divmod for Decimal uses truncate instead of floor as builtin # divmod, so we have to do it manually here. a, b = val - low, high - low div = (a / b).to_integral(ROUND_FLOOR) mod = a - div * b # if we were not usig Decimal, it would look like this. # div, mod = divmod(val - low, high - low) mod += low return int(div), mod
