def _handleConstants(self):
self.constsdef = {
"Gravity": constants.gravity(),
"StefanBoltzmann": constants.stefan_boltzmann(),
"PermittivityOfVacuum": constants.vacuum_permittivity(),
"BoltzmannConstant": constants.boltzmann_constant(),
}
def __init__(self, obj):
super(ConstantVacuumPermittivity, self).__init__(obj)
obj.addProperty("App::PropertyVacuumPermittivity",
"VacuumPermittivity", "Constants",
"Set the permittivity of vacuum")
obj.VacuumPermittivity = Units.Quantity(
constants.vacuum_permittivity())
def __init__(self, obj):
super(ConstantVacuumPermittivity, self).__init__(obj)
obj.addProperty(
"App::PropertyVacuumPermittivity",
"VacuumPermittivity",
"Constants",
"Overwrites default permittivity of vacuum"
)
# we must set an expression so that the small value can actually be entered
permittivity = Units.Quantity(constants.vacuum_permittivity()).getValueAs("F/m")
obj.setExpression("VacuumPermittivity", str(permittivity))
Console.PrintMessage("The unit schema mm/kg/s is used. So export and "
"import is done in standard FreeCAD units.\n")
UNITS = {
"L": "mm",
"M": "kg",
"T": "s",
"I": "A",
"O": "K",
"N": "mol",
"J": "cd",
}
CONSTS_DEF = {
"Gravity": constants.gravity(),
"StefanBoltzmann": constants.stefan_boltzmann(),
"PermittivityOfVacuum": constants.vacuum_permittivity(),
"BoltzmannConstant": constants.boltzmann_constant(),
}
def getFromUi(value, unit, outputDim):
quantity = Units.Quantity(str(value) + str(unit))
return convert(quantity, outputDim)
def convert(quantityStr, unit):
quantity = Units.Quantity(quantityStr)
for key, setting in UNITS.items():
unit = unit.replace(key, setting)
return float(quantity.getValueAs(unit))