Mathematica: GOTCHA: If a function is used to generate a control specification (or a grouping of control specifications in a layout) under some circumstances an 'Evaluate@' must be applied to the function for the control specification to be accepted.
SysMLv1: Cameo Simulation Toolkit: GOTCHA: Do not use Associations with Signal attributes, they will become null when fed as argument values for Parameters of 'effect' Behaviors of Transitions
SysMLv1.7/fUMLv1.4: Cameo Simulation Toolkit v2024x: Using an extending Enumeration literal as a parameter argument value runs but a WARN is issued.
fUML1.4: Cameo Simulation Toolkit: LIMITATION: CreateObjectAction is not allowed to instantiate a UML DataType or a SysMLValueType, only a Class as the CreateObjectAction::classifier! WORKAROUND: Use a ValueSpecificationAction instead with an instance.
GOTCHA: MagicDraw/Cameo: SysMLv1/UML: The argument context required to see results in Evaluation Mode for custom OpaqueBehavior scripts might not be the same as required for use in an Operation From Model for a Derived Property on a table column
GOTCHA: MagicDraw/Cameo: SysMLv1/UML: If you can extract model info using an OpaqueBehavior and you can see that in the Evaluation Mode in the Expression Editor it might not appear in a column in the Generic Table Diagram because the final Type is not set
GOTCHA: MagicDraw/Cameo: SysMLv1/UML: The 'name' of a Derived Property is parsed and sometimes displayed quite differently in column names. Be careful when mixing lower case and UPPER CASE in the middle of Derived Property names.
SysMLv1: MagicDraw/Cameo: INTRINSIC GOTCHA: Care must be taken with ownership of Activities used as UseCase scenarios vs the ‘subject’ of the UseCase. Make sure you don’t get an Activity ‘context’ mismatch! It's up to you to manage it as intended.
Mathematica: The output form of Mathematica follows internal rules that may not always correspond exactly to how a human might typeset it.
Webel: SysML4Mathematica: SysML Parametric Diagrams are not well suited to modelling calculations with Blocks for MTools classes, or for modelling complex logic flow of Mathematica functions. Prefer SysML Activity Diagrams for those modelling cases.
GOTCHA: Mathematica v13.2+: Operations on "DegreesFahrenheit" °F and "DegreesCelsius" °C are now performed using Kelvins (K). CASE: Naive percentage operation gives answer relative to Kelvins. Use "DegreesCelsiusDifference"/"DegreesFahrenheitDifference"!
In the course PDF for 'CED Engineering: Air Conditioning Psychrometrics (A.Bhatia)' the term "enthalpy (h)" usually refers to the mass-specific enthalpy per dry air (in CoolProp notation 'Hda')
[FIXED in v2022Refresh1]: BUG: MagicDraw/Cameo: 19SP3/v2022xGolden: Activity Diagrams: Pin display mode 'Position of Labels' does not stick, label positions in Diagrams have sometimes moved after re-opening a project [and "FIX"] ARCHIVAL (2022): This content is now considered historical only!
MagicDraw SysML: [v2022xGolden,v2022xRefresh1]: ISSUE: Automatic assignment of the Type of the 'result' of a ReadStructuralFeatureAction not working with drag & drop.
The integration between Wolfram Workbench and Mathematica is partly gammy (as of latest versions 2022-08-23)
CoolProp: Mathematica: Mac: HOWTO get CoolProp for Mathematica running on Apple M1 Max and Mathematica13
CoolProp: HOWTO reproduce a pressure vs specific enthalpy chart in Mathematica. Example: R32 refrigerant.
Mathematica: MTools: Argument Pattern strong type matching does not intrinsically respect inheritance (makes implementing design-by-contract and some Design Patterns less convenient). But you can use PatternTests with Webel MAll extensions.
Mathematica + Magic Model Analyst (Cameo Simulation Toolkit) for SysML Parametrics: GOTCHA: You must use a regular '=' on the SysML side, not the Mathematica '==' (or it will be intepreted as a constraint condition to test, not an equation to solve).
Cameo Simulation Toolkit: v19SP3: GOTCHA/BUG: When a Property is typed by an abstract Block an instance of a concrete specialising Block (where available) will automatically be created and assigned even when the lower multiplicity is 0
MagicDraw/Cameo 19SP3/v2022xGolden: [FIXED in v2022xRefresh1]: Activity Diagrams: Pin display mode 'Position of Labels' does not work correctly for 'Name And Type Labels Inside', only shows the Name inside (not the Label) [and WORKAROUND] ARCHIVAL (2022): This content is now considered historical only!
TIP/GOTCHA: MagicDraw SysML/Cameo: In Parametric Diagrams create BindingConnectors involving part properties by selecting the constraint parameter symbol first and use the smart manipulator (otherwise you might accidentally create a regular Connector)
UML: Cameo Simulation Toolkit 19SP3: GOTCHA: CreateObjectAction ignores an Artifact as 'classifier' even though Artifact is a Classifier
UML/SysML: Cameo Simulation Toolkit 19SP3: A parent Activity with a DecisionNode that uses a Activity as a decisionInput Behavior terminates immediately after the decisionInput terminates (but OpaqueBehavior works)
UML/SysML: MagicDraw/Cameo: WARNING: If you assign a value to a Slot for an untyped Property then assign a ValueType later it will DELETE your assigned value! Assign a type first .
The SysML1.6 derived /tracedTo is only available on AbstractRequirement (but in MagicDraw/Cameo you can use derived relationships to achieve the same thing on other kinds of NamedElement).
The UML «Trace» and SysML Trace can't be applied to a Slot as target (because Slot is just an Element, not a NamedElement).
MagicDraw/Cameo v19SP3: The display of units can't be disabled on the initialValues compartment for context-specific values, which can lead to inconsistencies when an OpaqueExpression that references value property names is used.
MagicDraw/Cameo v19SP3: vs SysPhS-1.1: OpaqueExpression for Slot value exports to Modelica as 'null' if only uses a single variable. WORKAROUND/HACK prefix the variable with '1 *' [FIXED in v2021x]
SysPhS vs Modelica: If you redeclare a PhSConstant (Modelica parameter) as a PhSVariable (Modelica variable) Modelica still treats it as a 'parameter'. You can end up with an unbalanced system with one equation too many!
MagicDraw/Cameo v19SP3: vs SysPhS-1.1: Modelica export: Direct binding from a PhSVariable value property within a FlowProperty of a Port to an inner value property does not flatten. WORKAROUND: Use an intermediate constraint property.
MagicDraw/Cameo v19SP3: Does not support display of context-specific values on a FlowProperty symbol within a Port in an IBD
SysML vs Modelica: GOTCHA: Terminology: A 'connector' in Modelica is equivalent to the Type of a Port in SysML. A Connector in SysML-1.x is equivalent to a 'connect(source,target)' in Modelica.
MagicDraw/Cameo v19SP3+SysPhS-1.1: On export to Modelica sometimes repeats parts of an equation into an extending model.
MagicDraw/Cameo v19SP3+SysPhS-1.1: Does not cleanly export INLINE Modelica 'if/then/else' statements (a.k.a. "switching" form)
MagicDraw/Cameo: GOTCHA: When applying a numerical default to a value property make sure the value property has already been typed by Real or Integer (or a ValueType that extends one of them) otherwise it will assign a LiteralString as default.
SysPhSLibrary and ISO-80000 ModelLibrary: Some ValueType names and Unit symbols are not Modelica-friendly
MagicDraw/Cameo v19SP3: SysPhS: If you have a custom ValueType it MUST extend Real either directly or indirectly or it will not be seen on export to Modelica.
SysML: Naming: You may include Block, ValueType, and Signal names in the names of Behaviors (such as Activities) as long as this does not undermine the principles of functional analysis and allocation.
SysML: Naming: Including Block, ValueType, and Signal names in the names of Behaviors (such as Activities) can sometimes undermine purist functional allocation (because it may presuppose the element of the physical solution that carries out the function).
SysML: The placement of usages of Blocks, their Ports, and Connectors in an Internal Block Diagrams DOES NOT necessarily represent physical geometry!
MagicDraw/Cameo v19SP3 vs SysML&SysPhS: Export to Modelica: The exported layout annotations appear to be completely broken (at least vs Wolfram SystemModeler) just de-select generation of them on export.
GOTCHA: MagicDraw SysML/Cameo 19SP3: Export to Modelica: The name of a redefining Property must be exactly the same as the Property it redefines or it will not export properly!
Wolfram SystemModeler: On Mac the Unit Conversions dialog is under SystemModeler -> Preferences -> Global -> Unit Conversion (rather than under Tools -> Options)
Wolfram SystemModeler: GOTCHA: The conversion dialog will not offer the Add Unit Conversion button unless there is not already an existing conversion in BOTH directions.
MagicDraw/Cameo: If you drag a Behavior from the model browser onto the SYMBOL of a State (that does not already own the Behavior) and set it as an 'entry', 'doActivity', or 'exit' Behavior a "wrapper" Behavior owned by the State will be created.
MagicDraw SysML/Cameo 19SP3: GOTCHA: If you drag a Behavior from the model browser onto the 'entry', 'doActivity', or 'exit' field in a specification dialog of a State it WILL BECOME OWNED by the State (which "steals ownership")!
MagicDraw/Cameo v19SP3 vs SysML&SysPhS: GOTCHA: Will NOT correctly export a SysML-1.6 «~interfaceBlock» to Modelica (but does cope with a tilde ~ prefix in the name of a plain InterfaceBlock)
MagicDraw/Cameo vs SysML&SysPhS: GOTCHA: Will NOT export a non-normative System «system» block to Modelica, it only recognises a plain Block «block»!
SysPhS-1.1: GOTCHA: The term "initial values" is sometimes just used to refer to the start values for a simulation run in Modelica or Simulink. It does NOT always mean the additional context-specific values mechanism of SysML beyond Property::defaultValue
SysML: Using redefined Property and Property::defaultValue to create deep hierarchical value configurations of "initial values" configurations for SysPhS simulation is notoriously fiddly and requires experience and patience. Better tool support is needed!
There is no «port» stereotype keyword for Port or Property in UML-2.5.1 or SysML-1.6. It is assumed to be introduced in some SysML and SysPhS specification diagrams as a custom or user-defined stereotype for special illustration purposes.
MagicDraw/SysML vs SysPhS-1.1: Can't reproduce the "shortcut" property path representation of some properties nested within Ports as shortcut symbols fully inside the diagram frame. (Might be a specification diagram style issue.)
Webel vs SysPhS-1.1: Diagramming style: DO NOT recommend overlapping Connectors with "phantom" fork (or junction) as shown in in 'Figure 48: Internal structure of the signal processor'
MDSysML/Cameo 19SP3 SysPhSLibrary vs SysPhS-1.1: SimulinkBlock and ModelicaBlock specialise ExternalModel not Block
MDSysML/Cameo 19SP3: The SysPhS versions of Conductance, Frequency, siemens, and hertz, are not explicitly provided in the MagicDraw/Cameo model library
Modelica: GOTCHA: Sometimes the name 'p' is used for any Pin (such as on Ground) and sometimes 'p' is used for a specifically PositivePin (as opposed to 'n' for NegativePin).
MDSysML/Cameo: SysPhSLibrary: GOTCHA: You must set the additional 'k2' parameter for Modelica to be minus to achieve subtraction
SysPhS-1.1: p.57: GOTCHA: Table 11.3.2.5 Mathematical components: Mathematical.Subtraction maps to Math.Add (in Modelica) and Sum (in Simulink)
GOTCHA: MD SysML/Cameo 19SP3 vs SysPhS-1.1: Export to Modelica does not see a 'doActivity' on a State (does not write it to a Modelica algorithm), you MUST use an 'entry'!
GOTCHA: MagicDraw SysML/Cameo 19SP3: Export to Modelica: 'entry', 'doActivity', or 'exit' Behaviors of a State must be directly owned (not just "wrapped") or they won't be seen on export!
MagicDraw SysML/Cameo: GOTCHA: Export to Modelica only includes owned Constraints (not just applied Constraints) under the 'equation' export
MagicDraw SysML/Cameo: GOTCHA: A Constraint created and applied to a ConstraintBlock via the sidebar menu is NOT owned by the ConstraintBlock!
CAVEAT: The current Font Awesome icon used for 3D views is in fact actually a Unity branding icon [as a placeholder] that WILL change.
WARNING: In natural language casual conversation one often hears people speaking of a digital twin "replicating" or "twinning" a physical entity. If you do it that way literally, you will NOT have anything to manage the control system loop!
SysML does NOT distinguish between 'assembly' and 'delegation' Connector kinds (because of its more complex support for nested ports). These Connector type classifications are only relevant in UML.
UML-2.5.1 does NOT permit a trigger or guard on a Transition from an initial pseudostate in a StateMachine but Cameo/MagicDraw does (please avoid).
Webel: SysMLv1: MagicDraw/Cameo: AVOID the "default" SysML Item Flow Creation Mode 'Between Part Types' completely. Use 'Direct' mode, change it as soon as you start any SysML project under Options → Project → General → SysML [Helps prevent a clash/issue]
GOTCHA: Just because an InitialNode MAY have more than one outgoing ControlFlow and offers tokens on every outgoing ControlFlow does NOT mean that every outgoing edge takes a control token; InitialNode does NOT act like an implicit fork!
MagicDraw/Cameo: GOTCHA: ‘entry’, ‘exit’, ‘doActivity’ are all subsets of ‘ownedElement’; to use an existing Activity without changing its owner you need to create a “wrapper” Activity. Beware the tool does not simply move your Activity!
MagicDraw/Cameo: The context menu item 'Tools > Define Context-Specific Value' will only ever be available in an Internal Block Diagram on a part property symbol typed by a Block that has a value property!
MagicDraw/Cameo: The context menu item 'Tools > Define Context-Specific Value' will only be available UNTIL you have assigned one! Thereafter it does not appear anymore because the tool will have already created a tree of instances to carry the values.
Visual nesting of InstanceSpecification symbols has no meaning in the underlying model, only assignment to a Slot does!
MagicDraw/Cameo: In SysML Activity Diagrams you can only set the allocation mode in to 'usage' or 'definition' for an entire AllocateActivityPartition group at once, not for individual AllocateActivityPartition columns or rows.
MagicDraw/Cameo: In a Dependency Matrix the mode 'Show Element = All' can lead to very large matrices (but it enables you to interactively create relationships for elements that don't yet have any).
MagicDraw/Cameo: If you must use the Documentation field in the specification dialog for a Requirement element DO NOT use it to state the Requirement because that is WET not DRY. Instead just use the Requirement 'name' and/or the 'text'.
MagicDraw/Cameo: Using the display option to show labels inside Port rectangle symbols or to use SysML compartments on Port symbols hides any flow direction indicators.
The UML InformationFlow notation and the SysML ItemFlow notation can sometimes clash with the notation of named Associations and named and typed Connectors
In SysML the NOW DEPRECATED (since SysML-1.6) direct UML Port conjugation does not work consistently with SysML DirectedFeature and SysML FlowProperty on nested ports!
MagicDraw/Cameo 19SP3 still supports the DEPRECATED UML Port conjugation (but it is recommended here that you DO NOT use it, even though there might be future migration for such directly conjugated Ports).
Until tool support for ~InterfaceBlock comes you have to make a decision: (1) Bake your own «~InterfaceBlock» then deal with clashes when tool support comes; (2) stick with the DEPRECATED UML conjugation (not nested-port friendly) and await migration.
Provided/required Interface "lollipop" and "socket" (a.k.a. ball-and-socket) notation can quickly lead to clutter in UML Composite Structure Diagrams and SysML Internal Block Diagrams. SysML provided/required DirectedFeature notation is cleaner.
[HISTORICAL] ISSUE: UML: MagicDraw UML: Showing Port labels (name and type) inside Port rectangle symbols does not always work well with provided/required Interface "lollipop" and "socket" (a.k.a. ball-and-socket) notation ARCHIVAL (2021): This content is now considered historical only!
The mechanism for conjugated Ports has been changed in SysML 1.6, it now conjugates the Type! If you are using an InterfaceBlock to type a Port you can conjugate that 'original' on another Port by typing it with an ~InterfaceBlock.
AVOID "mixed" functional (behavioral) allocation levels! DO NOT Allocate from Usage level (Action) to Definition level (Block) or from Definition level (Activity) to usage level (part Property) - even if formally permitted in SysML.
DO NOT use Property names that are identical to the names of the Classifier (Class, DataType, Block, ValueType) that type them!
The SysML block compartment name 'initialValues' for what are really "context-specific values" is confusing - even completely misleading; please just think of them as 'contextValues' (and initial values as a special context case)
Webel recommends when using MagicDraw/Cameo: AVOID the "elided Pin" abstract ObjectNode notation on Activity Diagrams, use explicit Pins!
MagicDraw/Cameo tool support for Association composition "trees" is not good, and they end up being fiddly to maintain (and they can also cause issues for InformationFlows). Avoid them!
Webel: SysMLv1/UML: MagicDraw/Cameo: AVOID the the vendor-specific «useCaseModel» stereotype for Model packages, it leads to confusion with the rectangular 'subject' notation
SysML: MagicDraw/Cameo: DO NOT use the FlowPort or FlowSpecification menu items or smart manipulator items they are completely OBSOLETE (they create fully DEPRECATED SysML model element types)! Use FlowProperty on Block features instead.
It is NOT true in SysML1.6+ that you "should" always use a SysML FullPort or a SysML ProxyPort instead of a "standard" Port, and it's not even always a good idea (and the spec states this very clearly in multiple places)!
