Handler classes related to residuals¶

Residuals are used both by Model and by simu.ThermoContribution.

Residual¶

class simu.core.utilities.residual.Residual¶

Class representing a single residual.

The post-constructor will raise a DimensionalityError if the tolerance unit is not compatible with the value unit.

A possible offset in the tolerance unit, such as in degrees Celsius or gauge pressures, will be eliminated automatically. That is:

>>> from simu import SymbolQuantity as S, Quantity as Q
>>> val = S("r", "barg")
>>> r1 = Residual(val, Q(1e-7, "barg"))
>>> r2 = Residual(val, Q(1e-7, "bar"))
>>> f"{r1.tolerance - r2.tolerance:.15f~}"
'0.000000000000000 bar'

(there is a silly rounding error, hence the trick with the formatting to make this doctest work)

value: Quantity¶: The value as a symbolic quantity

tolerance: Quantity¶: The absolute tolerance of the residual as a numeric quantity in the same physical dimensions as the value

__init__( value: Quantity, tolerance: Quantity, ) → None¶

ResidualHandler¶

class simu.core.utilities.residual.ResidualHandler¶

This class, being instantiated as the simu.Model.residuals attribute, allows to define residuals, i.e. process constraints.

__init__()¶

add( name: str, residual: Quantity, tol_unit: str, tol: float = 1e-07, )¶

Define a residual, to approach zero withing its tolerance when the model is solved.

Parameters:

name – A unique name within the local context
residual – The residual to be zero.
tol_unit – The unit of the tolerance, which must be compatible with the unit of the residual quantity.
tol – The tolerance value. A normal recommendation is to give 1e-7 for a typical unit of measurement, which for extensive variables is largely problem size dependent. An industrial flow is typically characterized by kg/h, while a lab scale experiment can operate with g/h.

create_proxy() → Mapping[str, Residual]¶: Create a proxy object

ResiduaProxy¶

simu.core.utilities.residual.ResidualProxy¶: This is just a dictionary, mapping the names (str) to the Residual objects