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Modelica

modelica.org

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81–90 of 118 posts

Re: Modelica

#81

Post by brap »

I don’t know what this is.

There’s not a single example on the landing page. There’s not a single example on any of the main links from the landing page.

But the landing page does have a merch store so you can buy mugs and hoodies and look at huge company logos of “organizational members”, whatever that is.

You made something. Show me what you made. I’m probably not going to spend more than 30 seconds trying to figure it out unless I already know I need it.

Why make it so difficult?

Re: Modelica

#82

Post by bobim »

michaeltiller wrote: post #71
bobim wrote: post #59

Earlier quoted context omitted.

Ah! You're the author of Modelica by example?

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).

Nice to cross your path, I got the first one to kickstart myself some years ago (and still struggling with evaporation / condensation).

Would you recommend the second to introduce a colleague to OpenModelica? He is into gPROMS but will lose access to the software at retirement.

Sidenote: invest in software with freedom to operate and good knowledge reusability.

Re: Modelica

#83

Post by tompccs »

brap wrote: post #81

I don’t know what this is. There’s not a single example on the landing page. There’s not a single example on any of the main links from the landing page. But the landing page does have a merch store so you can buy mugs and hoodies and look at huge company logos of “organizational members”, whatever that is. You made something. Show me what you made. I’m probably not going to spend more than 30 seconds trying to figur…

"Modelica is an object oriented language to model cyber-physical systems."

Literally the first sentence.

Re: Modelica

#84

Post by lordnacho »

tompccs wrote: post #83
brap wrote: post #81

I don’t know what this is. There’s not a single example on the landing page. There’s not a single example on any of the main links from the landing page. But the landing page does have a merch store so you can buy mugs and hoodies and look at huge company logos of “organizational members”, whatever that is. You made something. Show me what you made. I’m probably not going to spend more than 30 seconds trying to figur…

"Modelica is an object oriented language to model cyber-physical systems." Literally the first sentence.

There's a big difference between showing and telling. GP wants a demo that makes it clear that something interesting has been produced.

Re: Modelica

#85

Post by guerrilla »

tompccs wrote: post #83
brap wrote: post #81

I don’t know what this is. There’s not a single example on the landing page. There’s not a single example on any of the main links from the landing page. But the landing page does have a merch store so you can buy mugs and hoodies and look at huge company logos of “organizational members”, whatever that is. You made something. Show me what you made. I’m probably not going to spend more than 30 seconds trying to figur…

"Modelica is an object oriented language to model cyber-physical systems." Literally the first sentence.

That doesn't mean anything to somone who doesn't already know what Modelica is. It would be hard to be more vague. C++ technically satisfies that definition.

Re: Modelica

#86

Post by djoldman »

brap wrote: post #81

I don’t know what this is. There’s not a single example on the landing page. There’s not a single example on any of the main links from the landing page. But the landing page does have a merch store so you can buy mugs and hoodies and look at huge company logos of “organizational members”, whatever that is. You made something. Show me what you made. I’m probably not going to spend more than 30 seconds trying to figur…

Agreed. I needed a few clicks to get to here:

https://mbe.modelica.university/behavior/equations/first_ord...

Re: Modelica

#87

Post by michaeltiller »

wolvesechoes wrote: post #79
alhirzel wrote: post #19

Earlier quoted context omitted.

Another up-and-coming solution is Julia's simulation ecosystem [1]. It is powered by the commercial organization behind the Julia programming language, which has received DARPA funding [2] to build out these tools. This ecosystem unifies researchers in numerical methods [3], scalable compute, and domain experts in modeling engineering systems (electrical, mechanical, etc.) I believe this is where simulation is headed…

"Another up-and-coming solution is Julia's simulation ecosystem" Still not comparable with Modelica that has proper specification, including graphical representation of models.

JuliaSim does have graphical representation, a GUI and an IDE. But, granted, it is also a commercial product, not open source.

Re: Modelica

#88

Post by michaeltiller »

bobim wrote: post #82
michaeltiller wrote: post #71

Earlier quoted context omitted.

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).

Nice to cross your path, I got the first one to kickstart myself some years ago (and still struggling with evaporation / condensation). Would you recommend the second to introduce a colleague to OpenModelica? He is into gPROMS but will lose access to the software at retirement. Sidenote: invest in software with freedom to operate and good knowledge reusability.

Modelica by Example is the most recent and free, so I would recommend that.

Re: Modelica

#89

Post by anothertroll123 »

aetherspawn wrote: post #74

OpenModelica is teetering on the edge of something finally being good enough to replace Simulink without paying $20k+ per user per year. It is, perhaps, only a few toolboxes away (Simulink Test, Simulink Coverage, Simulink Coder).

Hehehe. Well, Simulink Coder (& Embedded Coder) is a biggy.

Re: Modelica

#90

Post by anothertroll123 »

michaeltiller wrote: post #73
anothertroll123 wrote: post #55

Earlier quoted context omitted.

This is a fair description. I want to use Modelica but I can't get out of the Simulink ecosystem just yet. Do you know if there's a decent C autocoding solution like that of Simulink?

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 hardware, for example). But it sounds like you might be talking about autocoding of an embedded controller. In that case, I'm not aware of any tools with that target. Part of this is because Modelica can be…

Interesting. Can you suggest one or two in particular? I'd be curious about that code.

And yes, I'm talking about autocoding of an embedded controller. Which also means the C code has to be ready for that (hard real time, carefully controlled calls to libraries, no heap allocation, etc.)

Right now Simulink embedded coder can be (and is) used to generate production code for all sorts of aerospace vehicles (rockets/spacecraft/drones/etc). The moment any Modelica tool can be used like this I'll take a very serious look.

This renews my interest in Modelica...

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