Well if you are interested in the intersection of software engineering and technical computing, I'd recommend Julia. I'm currently working on JuliaSim which is a Modelica like system built on top of Julia. So Julia…
It is exclusive to JuliaSim. But the tools generate MTK compatible component models so, once built, they can be used with MTK.
It is pretty wide spread in automotive. I think nearly all F1 teams use it (hard to know for sure since they are quite secretive, but it is very common in my experience)
It means the causality is not built into the components but instead decided once your system is defined. The point is that you can make a change to the causality without having to refactor major parts of your model. It…
Modelica by Example is the most recent and free, so I would recommend that.
JuliaSim does have graphical representation, a GUI and an IDE. But, granted, it is also a commercial product, not open source.
Well most Modelica tools generate C code. I think all of them also generate FMUs (lookup Functional Mockup Interface, if you don't know what an FMU is). Some FMUs are source code FMUs (suitable for running on HiL…
Just to be clear, there is absolutely nothing "corporate" about that web site. It is a non-profit organization.
Yes. And "Introduction to Physical Modeling with Modelica". I also built the Modelica Playground (which I deliberately didn't link to because a thundering herd of HN readers would have crashed it).
The Modelica Association is a non-profit that publishes the specification, the standard library and all conference proceedings for free. We sell merch in part because people in the Modelica community like the language…
Modelica is nearly 30 years old, BTW.
OK, those are three quite different things. Modelica allows you to create models in a similar way to spice by describing components and how they are connected. But instead of a netlist of nodes, Modelica has a concept…
Modelica not only has discrete events (see other comment), it includes support for synchronous (clocked) systems of equations directly in the language. These kinds of language semantics are necessary if you want to have…
Over 20 years ago I modeled an internal combustion engine, an automatic transmission and a multibody chassis model all in a single model. IIRC, the model had something like 250,000 equations in it and it modeled…
Modelica by Example is a textbook on Modelica, not a searchable index of models. It doesn't even cover the Modelica Standard Library in any details much less the many other Modelica libraries out there. To determine if…
I actually would disagree that Bond Graphs are the "underlying mechanism" in Modelica. The Modelica community and the Bond Graph community are a bit at odds in fact. My side of this story can be found at [1] and [2]. I…
That's an interesting way of framing it. I tend to agree. It isn't so much the presence of the type system so much as the fact that the compiler is given sufficient information (much of it symbolic) to aggressively…
Chris, I agree that the symbolic processing is quite important. I've often made the argument that a purely numerical approach just can't compete because of the optimizations and insights that come out of the symbolic…
FYI, it is by the same people who initiated the Modelica effort (Hilding Elmqvist and Martin Otter). I think part of the goal was to shed having to maintain a whole language (and the need to specify all the semantics…
But, of course, what is solvable changes and/or is implementation dependent. Modelica doesn't say much on the topic of impulses. In theory, a vendor could support variable index systems along with the ability to resolve…
Very true. But I think it is important to understand the alternative. The "object-oriented" part of Modelica is intended to make creating large scale models manageable. You make it sound like the object-oriented…
Well if you are interested in the intersection of software engineering and technical computing, I'd recommend Julia. I'm currently working on JuliaSim which is a Modelica like system built on top of Julia. So Julia…
It is exclusive to JuliaSim. But the tools generate MTK compatible component models so, once built, they can be used with MTK.
It is pretty wide spread in automotive. I think nearly all F1 teams use it (hard to know for sure since they are quite secretive, but it is very common in my experience)
It means the causality is not built into the components but instead decided once your system is defined. The point is that you can make a change to the causality without having to refactor major parts of your model. It…
Modelica by Example is the most recent and free, so I would recommend that.
JuliaSim does have graphical representation, a GUI and an IDE. But, granted, it is also a commercial product, not open source.
Well most Modelica tools generate C code. I think all of them also generate FMUs (lookup Functional Mockup Interface, if you don't know what an FMU is). Some FMUs are source code FMUs (suitable for running on HiL…
Just to be clear, there is absolutely nothing "corporate" about that web site. It is a non-profit organization.
Yes. And "Introduction to Physical Modeling with Modelica". I also built the Modelica Playground (which I deliberately didn't link to because a thundering herd of HN readers would have crashed it).
The Modelica Association is a non-profit that publishes the specification, the standard library and all conference proceedings for free. We sell merch in part because people in the Modelica community like the language…
Modelica is nearly 30 years old, BTW.
OK, those are three quite different things. Modelica allows you to create models in a similar way to spice by describing components and how they are connected. But instead of a netlist of nodes, Modelica has a concept…
Modelica not only has discrete events (see other comment), it includes support for synchronous (clocked) systems of equations directly in the language. These kinds of language semantics are necessary if you want to have…
Over 20 years ago I modeled an internal combustion engine, an automatic transmission and a multibody chassis model all in a single model. IIRC, the model had something like 250,000 equations in it and it modeled…
Modelica by Example is a textbook on Modelica, not a searchable index of models. It doesn't even cover the Modelica Standard Library in any details much less the many other Modelica libraries out there. To determine if…
I actually would disagree that Bond Graphs are the "underlying mechanism" in Modelica. The Modelica community and the Bond Graph community are a bit at odds in fact. My side of this story can be found at [1] and [2]. I…
That's an interesting way of framing it. I tend to agree. It isn't so much the presence of the type system so much as the fact that the compiler is given sufficient information (much of it symbolic) to aggressively…
Chris, I agree that the symbolic processing is quite important. I've often made the argument that a purely numerical approach just can't compete because of the optimizations and insights that come out of the symbolic…
FYI, it is by the same people who initiated the Modelica effort (Hilding Elmqvist and Martin Otter). I think part of the goal was to shed having to maintain a whole language (and the need to specify all the semantics…
But, of course, what is solvable changes and/or is implementation dependent. Modelica doesn't say much on the topic of impulses. In theory, a vendor could support variable index systems along with the ability to resolve…
Very true. But I think it is important to understand the alternative. The "object-oriented" part of Modelica is intended to make creating large scale models manageable. You make it sound like the object-oriented…