def _unit_class_mul(self, other):
"""Multiply a Unit by an object.
If other is another Unit, returns a new composite Unit.
Exponents of similar dimensions are added. If self and
other share similar BaseDimension, but
with different BaseUnits, the resulting BaseUnit for that
BaseDimension will be that used in self.
If other is a not another Unit, this method returns a
new Quantity... UNLESS other is a Quantity and the resulting
unit is dimensionless, in which case the underlying value type
of the Quantity is returned.
"""
if is_unit(other):
if self in Unit._multiplication_cache:
if other in Unit._multiplication_cache[self]:
return Unit._multiplication_cache[self][other]
else:
Unit._multiplication_cache[self] = {}
# print "unit * unit"
result1 = {} # dictionary of dimensionTuple: (BaseOrScaledUnit, exponent)
for unit, exponent in self.iter_base_or_scaled_units():
d = unit.get_dimension_tuple()
if d not in result1:
result1[d] = {}
assert unit not in result1[d]
result1[d][unit] = exponent
for unit, exponent in other.iter_base_or_scaled_units():
d = unit.get_dimension_tuple()
if d not in result1:
result1[d] = {}
if unit not in result1[d]:
result1[d][unit] = 0
result1[d][unit] += exponent
result2 = {} # stripped of zero exponents
for d in result1:
for unit in result1[d]:
exponent = result1[d][unit]
if exponent != 0:
assert unit not in result2
result2[unit] = exponent
new_unit = Unit(result2)
Unit._multiplication_cache[self][other] = new_unit
return new_unit
elif is_quantity(other):
# print "unit * quantity"
value = other._value
unit = self * other.unit
return Quantity(value, unit).reduce_unit(self)
else:
# print "scalar * unit"
value = other
unit = self
# Is reduce_unit needed here? I hope not, there is a performance issue...
# return Quantity(other, self).reduce_unit(self)
return Quantity(other, self)
def cos(angle):
"""
Examples
>>> cos(180*degrees)
-1.0
"""
if is_quantity(angle):
return math.cos(angle/radians)
else:
return math.cos(angle)
def sin(angle):
"""
Examples
>>> sin(90*degrees)
1.0
"""
if is_quantity(angle):
return math.sin(angle/radians)
else:
return math.sin(angle)
def tanh(angle):
if is_quantity(angle):
return math.tanh(angle/radians)
else:
return math.tanh(angle)
def cosh(angle):
if is_quantity(angle):
return math.cosh(angle/radians)
else:
return math.cosh(angle)
def tan(angle):
if is_quantity(angle):
return math.tan(angle / radians)
else:
return math.tan(angle)
def cosh(angle):
if is_quantity(angle):
return math.cosh(angle / radians)
else:
return math.cosh(angle)
def sinh(angle):
if is_quantity(angle):
return math.sinh(angle / radians)
else:
return math.sinh(angle)